BMP2-Related Short Stature-Facial Dysmorphism-Skeletal Anomalies Syndrome

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Classifications

Harrison's Part

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Inheritance

1

Autosomal dominant HP:0000006

Heterozygous BMP2 loss-of-function variants and deletions may arise de novo or be inherited. In the 2017 family with two affected sisters, variant-specific assays detected somatic mosaicism in their clinically unaffected father; transmission to both daughters also establishes germline involvement. Routine blood sequencing did not detect the mosaic variant in that father.

Autosomal dominant inheritance

Show evidence (1 reference)

PMID:29198724 SUPPORT Human Clinical

"De novo occurrence and autosomal-dominant inheritance of variants, including paternal mosaicism in two affected sisters who inherited a BMP2 splice-altering variant, were observed across all reported families."

Establishes dominant transmission and documents paternal mosaicism, which matters for recurrence counselling in apparently de novo families.

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Discussions and Knowledge Gaps

2

What is the neurodevelopmental spectrum attributable to isolated BMP2 loss, and how do multigene deletions and additional variants modify it?

KNOWLEDGE GAP OPEN bmp2_developmental_delay_extent

Attached to

phenotypes#Delayed speech and language development pathophysiology#BMP2 Haploinsufficiency

The 2017 cohort reported normal cognitive development, whereas later series include speech delay and occasional broader developmental concerns. Interpretation is limited by mixed genotypes and incomplete formal testing. Relatives carrying the same multigene deletion may differ in developmental outcome; this supports variable expressivity and does not exclude a contribution from the deletion. Cohorts restricted to intragenic variants or BMP2-only deletions, with standardized assessment, are needed.

Show evidence (3 references)

PMID:39970956 SUPPORT Human Clinical

"The degree of developmental delay is still controversial."

The controversy stated by the authors of the most recent cohort.

PMID:39970956 SUPPORT Human Clinical

"We propose that global developmental delay is either a rare part or not part of the phenotype."

The 2025 authors propose that global delay is rare or absent from the core phenotype, but this remains unresolved.

PMID:22965927 SUPPORT Human Clinical

"The father was otherwise healthy with no history of FTT or DD, suggesting high penetrance, yet variable expressivity for haploinsufficiency of BMP2."

Father and son with the same multigene deletion differed in developmental outcome. Such discordance does not establish that the deletion is unrelated to the delay.

Does BMP2 contribute to determination of the cardiac axis in humans, beyond its established role in septal and valvuloseptal morphogenesis?

KNOWLEDGE GAP OPEN bmp2_cardiac_laterality

Attached to

pathophysiology#Failed Endocardial Cushion Mesenchymal Transition phenotypes#Congenital heart disease

One family with a BMP2 frameshift variant included a proband with isolated dextrocardia and situs solitus, with no other viscus displaced and no structural cardiac defect. Laterality is a distinct developmental question from cushion transformation, and a single proband cannot separate a real BMP2 laterality role from coincidence. The reporting authors say so themselves. It is recorded here so that dextrocardia is not silently folded into the cardiac-anomaly phenotype, where it would imply a mechanism the evidence does not support.

Show evidence (2 references)

PMID:37572998 SUPPORT Human Clinical

"In addition to short stature, impaired hearing ability and minor skeletal deformities, the proband exhibited isolated dextrocardia situs solitus without cardiac anomalies and abnormal locations of other visceral organs."

The single observation the question rests on, including that it occurred without any structural cardiac defect.

PMID:37572998 SUPPORT Human Clinical

"further studies are needed to assemble more cases to elucidate BMP2 role in human heart development"

The authors' own statement that the laterality claim is not established.

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Pathophysiology

13

BMP2 Haploinsufficiency

Loss of one functional BMP2 allele is the principal model for this disorder. Overlapping human phenotypes with intragenic variants and deletions, together with growth and rib abnormalities in heterozygous knockout mice, support dosage sensitivity. These observations do not quantify secreted ligand in patients or exclude other effects of individual mutant proteins.

BMP2 hgnc:1069

BMP2 growth factor activity GO:0008083 ↓ DECREASED

Experimental models

Patient lymphoblast BMP2 splicing assay CELL LINE RT-PCR of lymphoblast RNA and sequencing of isolated amplicons identifies aberrant processing of the familial intron 1 splice-acceptor variant.

Animal models

Heterozygous Bmp2 knockout mouse Mouse recapitulates Loss of one Bmp2 allele reproduces reduced body length and rib abnormalities. Patient ligand concentrations were not measured.

Zebrafish bmp2b ventralization assay for patient missense alleles Zebrafish measures Reads out whether a given missense allele retains BMP2 function, and so whether it belongs in the same loss-of-function class as the truncating alleles.

Downstream

Reduced Canonical BMP-SMAD Signalling Output Complete cranial neural crest Bmp2 deletion reduces mandibular SMAD phosphorylation. Reduced signaling is a proposed consequence of human haploinsufficiency; the dose-response and intervening receptor activity were not measured in patients.

Reduced Noncanonical p38 Signalling Output The same mouse deletion reduces mandibular p38 phosphorylation; relevance to human heterozygous loss is inferred.

Reduced Osteogenic Output of Skeletal Progenitors BMP2 and BMP4 jointly support osteoblast maturation in limb mesenchyme. The combined-knockout experiments establish a pathway requirement, not the magnitude of a human heterozygous BMP2 defect.

Failed Endocardial Cushion Mesenchymal Transition Myocardial Bmp2 is necessary for cushion induction in conditional-null mice. An equivalent defect has not been demonstrated in human BMP2 heterozygotes.

Deficient Skeletal Repair and Bone Homeostasis Complete limb-conditional Bmp2 loss impairs fracture repair. A repair defect from a single defective human allele remains unproven.

Reduced Cranial Neural Crest Chondrogenic Progenitors Complete neural crest Bmp2 deletion reduces Meckel cartilage progenitor proliferation and Sox9 expression; the human dosage threshold is unknown.

Wolff-Parkinson-White syndrome Pre-excitation has been reported with intragenic BMP2 loss and deletions. The conduction-system mechanism is unresolved and is not established by cardiac cushion experiments.

Show evidence (2 references)

PMID:29198724 SUPPORT Model Organism

"Additionally, we observed similarity to the human phenotype of short stature and skeletal anomalies in a heterozygous Bmp2-knockout mouse model, suggesting that haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions..."

The heterozygous knockout phenotype supports haploinsufficiency; it does not by itself exclude additional effects of individual human alleles.

PMID:19116164 SUPPORT Model Organism

"Whereas mice lacking a single copy of Bmp2 or Bmp4 are viable and have subtle developmental defects, compound mutants show embryonic and postnatal lethality due to defects in multiple organ systems including the allantois, placental vasculature, ventral body wall, skeleton, eye and heart."

Bmp2/Bmp4 interactions demonstrate dose sensitivity in mice. Single Bmp2 heterozygotes have skeletal defects, but survival and severity depend on background; the full text reports hydrocephalus and loss of some heterozygotes on C57BL/6J. These models do not establish human viability or severity thresholds.

Reduced Canonical BMP-SMAD Signalling Output

Mechanism confidence: Provisional

Canonical BMP pathway activity is reduced in mandibular bone and Meckel cartilage after complete Bmp2 deletion in the mouse cranial neural crest lineage, measured by pSmad1/5/8 staining. This provides a mechanistic model for BMP2-related craniofacial disease. Signaling was not measured across affected human tissues, and compensation by other BMP ligands is tissue-dependent.

BMP signaling pathway GO:0030509 ↓ DECREASED SMAD protein signal transduction GO:0060395 ↓ DECREASED

Downstream

Impaired Cranial Neural Crest Osteogenic Differentiation Reduced SMAD phosphorylation accompanies reduced osteogenic progenitors in the conditional mouse mutant. The experiment does not isolate SMAD-dependent mediation from the concurrent reduction in p38 activity.

Show evidence (1 reference)

PMID:30413887 SUPPORT Model Organism

"As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals."

Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement in heterozygous patients.

Reduced Noncanonical p38 Signalling Output

Mechanism confidence: Provisional

Phosphorylated p38 is reduced in the mandibular bone of cranial neural crest Bmp2 conditional-null mice alongside reduced canonical SMAD activity. The relative contributions of the two pathways to the progenitor defect have not been separated in this model.

p38 MAPK cascade GO:0038066 ↓ DECREASED

Downstream

Impaired Cranial Neural Crest Osteogenic Differentiation Reduced p38 activity and progenitor proliferation coexist after Bmp2 deletion; pathway-specific mediation remains unresolved.

Show evidence (1 reference)

PMID:30413887 SUPPORT Model Organism

"As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals."

Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement in heterozygous patients.

Impaired Cranial Neural Crest Osteogenic Differentiation

Mechanism confidence: Provisional

In Wnt1-Cre;Bmp2 flox/flox mice, cranial-neural-crest-derived mandibular mesenchyme has a reduced Sp7-positive osteogenic progenitor domain from E12.5 to E16.5. Reduced proliferation precedes the morphological mandibular defect. These observations support a developmental requirement for BMP2, without establishing a quantitative human heterozygous effect.

osteoblast CL:0000062

neural crest cell development GO:0014032 ⚠ ABNORMAL osteoblast differentiation GO:0001649 ↓ DECREASED

Animal models

Wnt1-Cre;Bmp2 flox/flox cranial neural crest conditional knockout mouse Mouse recapitulates Reduced proliferation and osteogenic differentiation of mandibular progenitors is measured directly in this model.

Downstream

Craniofacial Skeletal Hypoplasia

Show evidence (2 references)

PMID:30413887 SUPPORT Model Organism

"We observed that the domain expressing Sp7, a molecular marker for osteogenic progenitors, is reduced throughout this period in Wnt1-Cre;Bmp2f/f mice compared to that in wild-type controls"

The Sp7 expression domain was assessed from E12.5 to E16.5, directly supporting the osteogenic progenitor defect.

PMID:30413887 SUPPORT Model Organism

"the ratio of cell proliferation in the mandible of Wnt1-Cre;Bmp2f/f embryos was significantly reduced"

PHH3 staining identified reduced proliferation before the morphological defect.

Reduced Cranial Neural Crest Chondrogenic Progenitors

Mechanism confidence: Provisional

Complete Bmp2 loss in the mouse cranial neural crest lineage reduces Sox9 expression and proliferation in Meckel cartilage. The smaller transient cartilaginous support accompanies mandibular hypoplasia. This lineage-specific finding cannot be replaced by results from limb mesenchyme, where other BMP ligands can sustain much of chondrogenesis.

chondrocyte CL:0000138

Downstream

Craniofacial Skeletal Hypoplasia Reduced Meckel cartilage and osteogenic progenitors both occur in the mutant mandible; their separate causal contributions to bone hypoplasia were not isolated.

Show evidence (2 references)

PMID:30413887 SUPPORT Model Organism

"We found that both the expression area and the intensity of Sox9 are significantly reduced"

Sox9 staining supports the chondrogenic defect in Meckel cartilage of conditional-null embryos.

PMID:30413887 SUPPORT Model Organism

"These results show that a decreased ratio of cell proliferation leads to reduction of osteogenic and chondrogenic progenitor cells and is responsible for the formation of smaller mandible in the mutants"

The authors connect reduced progenitor proliferation to the smaller mandible in this model.

Craniofacial Skeletal Hypoplasia

Craniofacial skeletal underdevelopment includes mandibular and midfacial hypoplasia. Neural crest Bmp2 conditional-null mice show approximately 40% lower zygomatic volume and 10% shorter mandibular length. These model-specific measurements do not predict the magnitude of the human phenotype.

face morphogenesis GO:0060325 ⚠ ABNORMAL embryonic cranial skeleton morphogenesis GO:0048701 ⚠ ABNORMAL

Animal models

Wnt1-Cre;Bmp2 flox/flox cranial neural crest conditional knockout mouse Mouse partially recapitulates Micrognathia, cleft palate, zygomatic and mandibular hypoplasia are all reproduced.

Downstream

Midface retrusion

Micrognathia

Dental crowding Reduced jaw size is a plausible contributor; an independent dental developmental contribution has not been excluded.

Failure of Tongue Descent and Palatal Shelf Elevation A mandible too small to accommodate the tongue holds it high, where it obstructs the palatal shelves.

Eustachian Tube Dysfunction and Middle Ear Effusion Craniofacial anatomy is a proposed contributor to recurrent effusions, but the anatomical pathway has not been demonstrated specifically in this disorder.

Show evidence (1 reference)

PMID:30413887 SUPPORT Model Organism

"Lateral views of 3D reconstructions from microCT scans further confirmed severe craniofacial bone defects in mutant mice, including a ~ 40% reduction in the zygomatic volume and a ~ 10% reduction in the length of the mandibular bone with a missing coronoid process"

MicroCT quantifies hypoplasia in two craniofacial skeletal elements of conditional-null mice; these are not human effect-size estimates.

Failure of Tongue Descent and Palatal Shelf Elevation

In the neural crest Bmp2 conditional-null mouse, a small mandible prevents tongue descent and mechanically obstructs palatal shelf elevation. Removing the mandible and tongue permits elevation in embryonic head culture, and isolated shelves fuse in organ culture. Tongue volume, myogenic differentiation and palatal proliferation were preserved. Palatal BMP signaling was largely maintained, although posterior nasal-side pSmad1/5/8 was reduced; compensation by BMP4/BMP7 was proposed. The rescue supports a mechanical contribution without proving that all human BMP2-associated clefts follow this route.

roof of mouth development GO:0060021 ⚠ ABNORMAL

Experimental models

Embryonic head and isolated palate culture rescue OTHER E13.5 conditional-mutant heads cultured for 24 hours after tongue and mandible removal recover palatal elevation; isolated palatal shelves fuse during 72-hour organ culture.

Downstream

Cleft palate

Pierre-Robin sequence

Show evidence (4 references)

PMID:30413887 SUPPORT Model Organism

"Palate clefting is caused by the undescended tongue that prevents palatal shelf elevation."

Describes the tongue-position mechanism in the conditional-null mouse.

PMID:30413887 REFUTE In Vitro

"Bmp2 itself is not an intrinsic regulator of palatal shelf elevation and fusion."

Cultured mutant heads and palatal shelves retain elevation and fusion capacity after removal of the obstruction. This refutes an intrinsic failure of those processes under the tested culture conditions.

PMID:30413887 REFUTE Model Organism

"Our results demonstrate that, although Bmp2 is inactivated in CNC-derived mesenchymal tissues, the activities of BMP signaling in the mutant palate appear largely unaffected, most likely attributing to the functional redundancy by Bmp4 and Bmp7."

Most palatal signaling persisted, but the full text reports reduced posterior nasal-side pSmad1/5/8. Redundancy was inferred rather than directly tested by combined deletion in this experiment.

+ 1 more reference

Reduced Osteogenic Output of Skeletal Progenitors

Mechanism confidence: Provisional

In Prx1-Cre limb mesenchyme, combined deletion of Bmp2 and Bmp4 allows an initial bone collar but prevents sustained osteoblast maturation and trabecular or cortical bone formation. Osterix expression declines after birth. Loss of Bmp2 alone largely preserves early limb skeletal differentiation in this experiment, showing that the combined-knockout result is not a direct demonstration of the human monoallelic defect. Chondrogenic requirements differ by lineage and developmental stage.

chondrocyte CL:0000138 osteoblast CL:0000062

osteoblast differentiation GO:0001649 ↓ DECREASED

Downstream

Impaired Endochondral Bone Growth Failed osteoblast maturation interrupts endochondral bone formation in combined Bmp2/Bmp4 limb mutants. Its contribution to human BMP2 haploinsufficiency is inferred.

Show evidence (2 references)

PMID:17194222 SUPPORT INDIRECT Model Organism

"In contrast, we find that the loss of both BMP2 and BMP4 results in a severe impairment of osteogenesis."

Combined Bmp2/Bmp4 loss impairs completion of osteoblast differentiation; Bmp2 loss alone did not produce this severe limb phenotype.

PMID:17194222 REFUTE Model Organism

"However, in the condensations that do form, subsequent chondrogenic differentiation proceeds normally even in the absence of BMP2 and BMP7 or BMP2 and BMP4."

Chondrogenic differentiation continues in condensations that form in these limb-mesenchyme mutants, with a delay described in the full text. This does not refute BMP2-dependent chondrogenesis in other lineages, including Meckel cartilage.

Impaired Endochondral Bone Growth

Mechanism confidence: Hypothetical

Disrupted endochondral ossification is a plausible contributor to the growth and digital phenotype, supported by combined Bmp2/Bmp4 limb-mutant experiments. Normal growth hormone testing in some patients does not localize the defect specifically to the growth plate. In the heterozygous Bmp2 mouse studied in 2017, total body length was reduced but femoral and tibial lengths were unchanged.

endochondral ossification GO:0001958 ↓ DECREASED growth plate cartilage development GO:0003417 ↓ DECREASED

Downstream

Short stature A developmental skeletal contribution is plausible, but the precise cellular sequence in human heterozygotes is unresolved.

Brachydactyly A developmental skeletal contribution is plausible, but the precise cellular sequence in human heterozygotes is unresolved.

Short toe A developmental skeletal contribution is plausible, but the precise cellular sequence in human heterozygotes is unresolved.

Show evidence (1 reference)

PMID:17194222 SUPPORT INDIRECT Model Organism

"In contrast, we find that the loss of both BMP2 and BMP4 results in a severe impairment of osteogenesis."

The full text localizes failed osteoblast maturation to endochondral bone formation in compound limb mutants; it does not establish a primary growth-plate lesion in patients.

Deficient Skeletal Repair and Bone Homeostasis

Mechanism confidence: Hypothetical

Limb-conditional Bmp2-null mice develop spontaneous fractures that fail to heal, demonstrating a requirement for BMP2 in fracture repair. This provides a candidate mechanism for skeletal maintenance abnormalities, but neither a repair defect in human heterozygotes nor a causal connection to the single reported phalangeal osteolysis case has been established.

bone remodeling GO:0046849 ⚠ ABNORMAL

Animal models

Limb-conditional Bmp2 knockout mouse Mouse recapitulates Spontaneous non-healing fractures establish BMP2 as required to initiate bone repair.

Downstream

Phalangeal osteolysis Provisional cross-species hypothesis: non-healing fractures after complete mouse limb Bmp2 loss and osteolysis in one heterozygous patient are distinct observations, without a demonstrated causal bridge.

Show evidence (1 reference)

PMID:17099713 SUPPORT Model Organism

"Mice lacking the ability to produce BMP2 in their limb bones have spontaneous fractures that do not resolve with time."

Separates a postnatal bone-maintenance requirement for BMP2 from its developmental one. Note this is the homozygous limb-conditional null, not the heterozygote, so it establishes that the requirement exists rather than that a halved dose is enough to breach it.

Failed Endocardial Cushion Mesenchymal Transition

Mechanism confidence: Provisional

Myocardial Bmp2 is required for atrioventricular cardiac jelly formation, induction of endocardial epithelial-to-mesenchymal transition and AV myocardial patterning in conditional-null mice. This identifies one developmental pathway relevant to congenital cardiac malformations, without establishing that human heterozygosity causes cushion failure or explaining every reported cardiac feature.

endocardial cell CL:0002350

epithelial to mesenchymal transition involved in endocardial cushion formation GO:0003198 ↓ DECREASED

Experimental models

Chick atrioventricular endocardial-myocardial coculture CO CULTURE Antisense inhibition of BMP2 suppresses mesenchyme formation in AV endocardium cocultured with myocardium; recombinant BMP2 rescues the effect.

Animal models

AV myocardial Bmp2 conditional knockout mouse Mouse recapitulates Loss of cushion EMT, of cardiac jelly, and of AV myocardial patterning.

Downstream

Altered Cardiac Development Failure of cushion induction can disrupt AV septation and valves. The experiments do not explain human semilunar valve anomalies, aortopathy or electrical conduction abnormalities.

Show evidence (3 references)

PMID:16314491 SUPPORT Model Organism

"We show that Bmp2 has three functions in the AV canal: to enhance formation of the cardiac jelly, to induce endocardial EMT and to pattern the AV myocardium."

Assigns cushion induction to Bmp2 specifically, in the myocardial compartment that signals to the endocardium. Homozygous conditional inactivation, so it shows the signal is required rather than that halving it produces the human septal defects.

PMID:10362015 SUPPORT In Vitro

"Antisense oligodeoxynucleotides to BMP2 inhibited mesenchyme formation in AV endocardium cocultured with associated myocardium. This inhibitory effect was reversed by the addition of recombinant BMP2."

A loss-and-rescue experiment in explant culture, which is the cleanest demonstration that the BMP2 signal itself is what drives cushion mesenchyme formation. Independent of the mouse genetics and of a transgenic background.

PMID:10362015 SUPPORT INDIRECT In Vitro

"However, BMP2 enhanced the TGFbeta-induced initial phenotypic changes associated with endothelial-mesenchymal transformation."

In cultured chick AV endothelial cells, BMP2 enhanced TGF-beta-induced changes but was insufficient alone. This co-signal requirement does not establish the reason for incomplete human penetrance.

Altered Cardiac Development

Human BMP2 variants and deletions are associated with a variable cardiac spectrum including septal, outflow and valve abnormalities. Bicuspid aortic valve with progressive aortic dilatation has been described with an intragenic truncating variant. Mouse myocardial conditional and Bmp2/Bmp4 compound mutants demonstrate developmental requirements, but the pathways underlying individual human lesion classes remain unresolved.

Downstream

Congenital heart disease

Bicuspid aortic valve

Aortic root aneurysm

Show evidence (3 references)

PMID:29198724 SUPPORT Human Clinical

"These findings demonstrate the important role of BMP2 in human craniofacial, skeletal, and cardiac development and confirm that individuals heterozygous for BMP2 truncating sequence variants or deletions display a consistent distinct phenotype characterized by short stature and skeletal and..."

Establishes cardiac anomalies as part of the core phenotype in the defining series.

PMID:19116164 SUPPORT INDIRECT Model Organism

"Within the heart, BMP2 and BMP4 function coordinately to direct normal lengthening of the outflow tract, proper positioning of the outflow vessels, and septation of the atria, ventricle and atrioventricular canal."

These cardiac results arise from combined Bmp2/Bmp4 mutations. The full text reports no cardiac abnormalities in the Bmp2 single heterozygotes examined; compensation in patients was not measured.

PMID:19116164 REFUTE Model Organism

"whereas no cardiac abnormalities were detected in Bmp2−/+ single mutants"

Negative observation in single heterozygotes limits extrapolation of compound-mutant cardiac defects to human BMP2 haploinsufficiency.

Eustachian Tube Dysfunction and Middle Ear Effusion

Recurrent secretory otitis media with secondary conductive hearing impairment was documented in the 2025 cohort. Craniofacial anatomy is a proposed contributor. This mechanism applies to the documented conductive cases; it does not account for every hearing abnormality, including sensorineural loss described in a father with a multigene 20p12.3 deletion.

Downstream

Recurrent otitis media

Conductive hearing impairment

Delayed speech and language development Hearing loss and facial muscular hypotonia are proposed contributors to articulation difficulties. Their causal contributions were not tested, and developmental outcomes vary.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Four individuals had recurrent secretory otitis media and needed to go through myringotomy, all of them also had secondary conductive hearing impairment because of secretory otitis media."

Documents the effusion-to-conductive-loss sequence directly, including the intervention it required.

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Pathograph

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Phenotypes

53

Cardiovascular 8

Bicuspid aortic valve HP:0001647

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"We describe a patient harboring a novel de novo BMP2 nonsense variant, who exhibited craniofacial and skeletal features previously described for this trait and the novel findings of bicuspid aortic valve (BAV) and aortic root and ascending aortic aneurysm."

The single reported observation, in a patient with an intragenic nonsense variant.

Aortic root aneurysm HP:0002616

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"We describe a patient harboring a novel de novo BMP2 nonsense variant, who exhibited craniofacial and skeletal features previously described for this trait and the novel findings of bicuspid aortic valve (BAV) and aortic root and ascending aortic aneurysm."

Names the aneurysm alongside the valve lesion in the same patient.

Wolff-Parkinson-White syndrome HP:0001716

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"an electrocardiogram showed evidence of preexcitation consistent with Wolff–Parkinson–White syndrome (WPW)"

Preexcitation in a patient whose BMP2 lesion is intragenic, which is what separates this from the deletion-interval reports.

Congenital heart disease Abnormal heart morphology HP:0001627

Show evidence (2 references)

PMID:39970956 SUPPORT Human Clinical

"Haploinsufficiency of BMP2 is associated with short stature, skeletal malformations, hearing impairment, cleft palate and cardiac abnormalities including structural abnormalities and arrhythmias"

Names both structural defects and arrhythmia as part of the cardiac spectrum.

PMID:40285376 REFUTE Human Clinical

"Additional clinical evaluations, including echocardiography and metabolic studies, were unremarkable."

Refutes the claim that cardiac involvement is a constant feature: this patient has a confirmed de novo truncating BMP2 variant and entirely normal echocardiography. It is the direct evidence for incomplete cardiac penetrance.

Ebstein anomaly Ebstein anomaly of the tricuspid valve HP:0010316

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis."

The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.

Transposition of the great arteries HP:0001669

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis."

The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.

Ventricular septal defect HP:0001629

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis."

The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.

Valvular pulmonary stenosis HP:0034350

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis."

The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.

Ear 4

Low-set ears HP:0000369

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."

Listed among the craniofacial features documented photographically.

Posteriorly rotated ears HP:0000358

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."

Listed among the craniofacial features documented photographically.

Recurrent otitis media HP:0000403

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"In our cohort, delayed language development (4/5) and secretory otitis media (4/5) were common."

Gives the observed frequency (4/5) for secretory otitis media.

Conductive hearing impairment HP:0000405

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"The conductive hearing impairment detected in four individuals (4/5) in our cohort resulted from repeated secretory otitis media."

States both the frequency and that the loss is conductive and derived from the effusion.

Endocrine 1

Endocrinopathy Abnormality of the endocrine system HP:0000818

Coarse binding: source unspecified

Show evidence (1 reference)

PMID:37125634 SUPPORT Human Clinical

"We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies."

The reported spectrum expansion, without a denominator.

Eye 1

Hypertelorism HP:0000316

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."

Listed among the craniofacial features documented photographically.

Head and Neck 18

Midface retrusion VERY_FREQUENT HP:0011800

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"All individuals had specific craniofacial features, traits present in all individuals were dental crowding (6/6), midface hypoplasia (7/7) of different extent and long philtrum (7/7)."

Gives the observed frequency (7/7) for midface hypoplasia in the cohort.

Long philtrum VERY_FREQUENT HP:0000343

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"All individuals had specific craniofacial features, traits present in all individuals were dental crowding (6/6), midface hypoplasia (7/7) of different extent and long philtrum (7/7)."

Long philtrum was present in 7 of 7 individuals.

Dental crowding HP:0000678

Show evidence (2 references)

PMID:39970956 SUPPORT Human Clinical

"All individuals had specific craniofacial features, traits present in all individuals were dental crowding (6/6), midface hypoplasia (7/7) of different extent and long philtrum (7/7)."

Dental crowding was present in all 6 individuals with dental data.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Dental crowding ... 6/10 ... 60.0% ... Anterior open bite ... 5/10 ... 50.0%"

The adjacent dental rows in Table 1 report crowding and open bite separately; crowding affected 6/10 assessed individuals.

Micrognathia HP:0000347

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."

The photographic figure legend enumerating the gestalt in three individuals of the cohort, micrognathia among them.

Cleft palate HP:0000175

Show evidence (2 references)

PMID:21671386 SUPPORT Human Clinical

"Clinical features were significant for cleft palate and facial dysmorphism in all three patients, including Pierre-Robin sequence in two."

Cleft palate in all three patients of this series, two with BMP2 as the only deleted gene.

PMID:22965927 SUPPORT Human Clinical

"The father was otherwise healthy with no history of FTT or DD, suggesting high penetrance, yet variable expressivity for haploinsufficiency of BMP2."

An independent multigenerational 20p12.3 deletion family, replicating the clefting phenotype and giving the penetrance and expressivity reading directly: high penetrance, variable expressivity.

Pierre-Robin sequence HP:0000201

Show evidence (1 reference)

PMID:21671386 SUPPORT Human Clinical

"Clinical features were significant for cleft palate and facial dysmorphism in all three patients, including Pierre-Robin sequence in two."

Pierre Robin sequence in two of three patients with a BMP2-containing 20p12.3 deletion.

Downslanted palpebral fissures HP:0000494

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."

Listed among the craniofacial features documented photographically.

Broad forehead HP:0000337

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."

Listed among the craniofacial features documented photographically.

Thin upper lip vermilion HP:0000219

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"Distinctive facial features included broad forehead, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate along with commonly associated skeletal anomalies of short stature, fifth finger clinodactyly, and wide sandal gap."

Names a thin upper lip among the distinctive facial features of the BMP2 phenotype.

Synophrys HP:0000664

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Less common features noted in at least two individuals were conductive hearing impairment, low-set posteriorly rotated ears, synophrys, sternal deformity, delayed bone age in early childhood, and L5/S1 spondylolisthesis."

Synophrys is explicitly reported in the human cohort.

Anteverted nares HP:0000463

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Affected individuals share similar distinctive craniofacial features such as a broad forehead with temporal narrowing, a flat midface, anteverted nares, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate"

The 2017 cohort describes anteverted nares in the facial phenotype.

High palate HP:0000218

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Affected individuals share similar distinctive craniofacial features such as a broad forehead with temporal narrowing, a flat midface, anteverted nares, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate"

High-arched palate is included separately from cleft palate; neither finding is implied to occur in every individual.

Short nose HP:0003196

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Short nose ... 12/12 ... 100.0% ... Anteverted nares ... 12/12 ... 100.0%"

Adjacent Table 1 rows describe the nasal phenotype: short nose and anteverted nares each occurred in all twelve individuals. This is a clinically ascertained cohort, not a population penetrance estimate.

Narrow forehead HP:0000341

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Affected individuals share similar distinctive craniofacial features such as a broad forehead with temporal narrowing, a flat midface, anteverted nares, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate"

The clinical description reports temporal narrowing alongside a broad forehead. Table 1 separately records temporal narrowing in 8/10 assessed individuals.

Anterior open-bite malocclusion HP:0009102

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Anterior open bite ... 5/10 ... 50.0%"

Table 1 reports the feature and its assessed denominator. This is a small selected cohort, not a population penetrance estimate.

Epicanthus HP:0000286

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Epicanthal folds (3/7) | + | − | − | + | + | − | −"

The table reports this feature across the seven individuals. Relatedness and ascertainment limit generalization of the cohort proportion.

Everted lower lip vermilion HP:0000232

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Everted lower lip vermilion (5/7) | + | − | + | + | + | − | +"

The table reports this feature across the seven individuals. Relatedness and ascertainment limit generalization of the cohort proportion.

Narrow mouth HP:0000160

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Microstomia (1/7) | − | − | − | + | − | − | −"

Table 2 identifies the affected individual.

Integument 1

Toenail dysplasia HP:0100797

Show evidence (3 references)

PMID:39970956 SUPPORT Human Clinical

"G shows toenail dysplasia in Individual 5 at seven years of age."

A single documented observation in the cohort.

PMID:39970956 SUPPORT Human Clinical

"Toenail dysplasia | Yes | No | N/A | Yes | Yes | Yes | Yes"

Table 3 lists five affected individuals, one unaffected individual and one with unavailable data: 5/6 assessed.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Sandal gap ... 8/11 ... 72.7% ... Toenail dysplasia ... 3/11 ... 27.3%"

Table 1 distinguishes sandal gap (8/11) from toenail dysplasia (3/11); the latter contrasts with 5/6 in the 2025 cohort.

Limbs 4

Brachydactyly HP:0001156

Show evidence (2 references)

PMID:21671386 SUPPORT Human Clinical

"deep palmar flexion creases and short 5th fingers"

The proposita of the BMP2-only deletion family. Her mother and maternal grandmother, who carry the same deletion, are separately described with short fifth fingers, so this is the segregating hand phenotype rather than an isolated observation.

PMID:39970956 SUPPORT Human Clinical

"Note the dental crowding, sandal gap and the short toes."

The corresponding foot finding, documented photographically in a cohort individual.

Short toe HP:0001831

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Note the dental crowding, sandal gap and the short toes."

Short toes documented photographically in a cohort individual.

Sandal gap HP:0001852

Show evidence (3 references)

PMID:39970956 SUPPORT Human Clinical

"Note the dental crowding, sandal gap and the short toes."

Sandal gap documented photographically in a cohort individual.

PMID:39970956 SUPPORT Human Clinical

"Sandal gap (6/6) | + | + | N/A | + | + | + | +"

Table 2 reports sandal gap in all six individuals assessed.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Sandal gap ... 8/11 ... 72.7% ... Toenail dysplasia ... 3/11 ... 27.3%"

The 2017 foot findings include sandal gap in 8/11 assessed individuals; the neighboring toenail row describes a separate phenotype.

Clinodactyly of the 5th finger FREQUENT HP:0004209

Show evidence (2 references)

PMID:33247540 SUPPORT Human Clinical

"Distinctive facial features included broad forehead, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate along with commonly associated skeletal anomalies of short stature, fifth finger clinodactyly, and wide sandal gap."

Lists fifth finger clinodactyly among the commonly associated skeletal anomalies of the BMP2 phenotype.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Phalangeal abnormalities ... 10/10 ... 100.0% ... Fifth-finger clinodactyly ... 4/11 ... 36.4%"

Table 1 reports fifth-finger clinodactyly in 4/11 assessed individuals, supporting the FREQUENT band.

Musculoskeletal 11

Scoliosis HP:0002650

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"Other skeletal abnormalities included progressive thoracic scoliosis, which required surgical intervention at 13 years of age."

Scoliosis in a patient whose only BMP2 lesion is an intragenic nonsense variant, so no neighbouring gene is available to explain it.

Prominent sternum HP:0000884

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"F show Individual 6 at age 44 years, note the prominent sternal bone."

A sternal anomaly documented photographically in an adult cohort individual.

Phalangeal osteolysis HP:0002797

Show evidence (1 reference)

PMID:40285376 SUPPORT Human Clinical

"At 10 years old, she presented with short stature and skeletal radiographs revealed osteolysis in multiple phalanges."

Documents osteolysis in one individual; a case report cannot establish its frequency in the disorder.

Hypotonia in infancy OCCASIONAL Floppy infant HP:0008947

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"whereas two of them also had hypotonia in infancy (Individuals 4 and 7)"

Two of seven cohort individuals had infantile hypotonia.

11 pairs of ribs HP:0000878

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Skeletal anomalies include proportionate short stature, short fifth proximal phalanges, 11 pairs of ribs, and a wide sandal gap"

The 2017 human clinical results explicitly report reduced rib number; this is not inferred solely from mice.

Delayed skeletal maturation HP:0002750

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Less common features noted in at least two individuals were conductive hearing impairment, low-set posteriorly rotated ears, synophrys, sternal deformity, delayed bone age in early childhood, and L5/S1 spondylolisthesis."

The human cohort records delayed bone age in early childhood.

L5-S1 spondylolisthesis Spondylolisthesis at L5-S1 HP:0008489

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Less common features noted in at least two individuals were conductive hearing impairment, low-set posteriorly rotated ears, synophrys, sternal deformity, delayed bone age in early childhood, and L5/S1 spondylolisthesis."

The human cohort identifies the specific lumbosacral level of vertebral slippage.

Abnormal scapula morphology HP:0000782

Coarse binding: source unspecified

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Scapula abnormality (3/5) | + | + | N/A | + | + | − | −"

The feature is present, but summary and individual-cell counts disagree.

Abnormality of the vertebral column HP:0000925

Coarse binding: source unspecified

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Spinal anomalies (3/4) | + | N/A | N/A | N/A | + | + | −"

Table 2 reports spinal skeletal anomalies without detailing their morphology.

Pectus excavatum HP:0000767

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"the patient’s physical exam was notable for prominent pectus excavatum, joint laxity, velvety soft skin without atrophic scars or transparency"

The physical examination describes a depressed sternum separately from other reported sternal abnormalities.

Joint hypermobility HP:0001382

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"the patient’s physical exam was notable for prominent pectus excavatum, joint laxity, velvety soft skin without atrophic scars or transparency"

The report documents joint laxity without establishing generalized hypermobility.

Nervous System 4

Neural tube defect HP:0045005

Show evidence (1 reference)

PMID:37125634 SUPPORT Human Clinical

"We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies."

The reported spectrum expansion. Cited without a frequency because the abstract gives no denominator for these findings.

Structural brain anomaly Abnormal brain morphology HP:0012443

Coarse binding: source unspecified

Show evidence (1 reference)

PMID:37125634 SUPPORT Human Clinical

"We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies."

The reported spectrum expansion, without a denominator.

Delayed speech and language development HP:0000750

Show evidence (2 references)

PMID:39970956 SUPPORT Human Clinical

"The most reported developmental delay in our cohort was delayed speech (4/5), including articulation."

Gives the frequency and specifies that the delay is in the speech domain.

PMID:39970956 SUPPORT Human Clinical

"Altogether these results indicate that the delayed speech development is not associated with low intelligence or general developmental delay."

Supports curating this as an isolated speech phenotype rather than as a marker of global delay.

Obstructive sleep apnea HP:0002870

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Four individuals (F2-1, F2-2, S1, and S3) had obstructive sleep apnea diagnosed in childhood or adulthood."

Documents clinically diagnosed obstructive sleep apnea across childhood and adult ages.

Growth 1

Short stature HP:0004322

Show evidence (2 references)

PMID:39970956 SUPPORT Human Clinical

"All but one individual had short stature (6/7)"

The 2025 cohort count documents short stature in six of seven individuals; the tall seventh individual is distinct from these six.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"Height ≤ −2.0 SD ... 8/11 ... 72.7%"

The 2017 table reports 8/11 assessed individuals meeting the height threshold.

🧬

Genetic Associations

1

BMP2

Gene: BMP2 hgnc:1069 relationship_type: CAUSATIVE variant_origin: GERMLINE

Show evidence (5 references)

PMID:29198724 SUPPORT Human Clinical

"Here, we report a cranioskeletal phenotype due to monoallelic truncating and frameshift BMP2 variants and deletions in 12 individuals from eight unrelated families that share features of short stature, a recognizable craniofacial gestalt, skeletal anomalies, and congenital heart disease."

The defining series, establishing that truncating variants and deletions produce one shared phenotype.

PMID:39970956 SUPPORT Human Clinical

"One individual had a novel frameshift variant in BMP2, and six individuals had 1.3-3.7 Mb microdeletions, including BMP2."

Documents the two allele classes side by side in one cohort and gives the deletion size range.

PMID:40285376 SUPPORT Human Clinical

"Whole-exome sequencing identified a de novo heterozygous truncating variant (c.440C>G; p.Ser147*) in BMP2."

A representative de novo nonsense allele, on the reference transcript used across the literature.

+ 2 more references

🔬

Variants

5

NM_001200.3:c.-7-2_-7-1delAGinsCC

Gene: BMP2 hgnc:1069 splice acceptor dinucleotide replacement

Genomic context: intron 5' UTR

Variant at the splice acceptor of untranslated intron 1. Two affected sisters inherited it from a clinically unaffected mosaic father. Routine blood sequencing was negative in the father, while variant-specific testing of other tissues established mosaicism.

Functional effects

RNA splicing

Patient lymphoblast RNA contains additional products retaining only 61 or 28 nucleotides of exon 2. A 240-amino-acid truncated protein is predicted; production, function and decay of these transcripts were not experimentally resolved.

Show evidence (2 references)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"a splice-altering variant, c.−7−2_−7−1delAGinsCC, which deletes AG and inserts CC at the splice acceptor site"

Identifies the 5-prime untranslated intron 1 splice-acceptor substitution in family 1, reported on NM_001200.3.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT In Vitro

"Sanger sequencing of gel-purified PCR products revealed that band 4 contained 61 nucleotides of exon 2, whereas band 5 contained only 28 nucleotides from exon 2"

Patient lymphoblast RT-PCR and sequencing identified two additional cryptic splice products. Wild-type and naturally alternatively spliced products were also present; protein abundance and nonsense-mediated decay were not measured.

BMP2 c.313C>T (p.Arg105Ter)

Gene: BMP2 hgnc:1069 single nucleotide variant

Variant detail: nonsense

A de novo nonsense variant reported in the patient with bicuspid aortic valve, progressive aortic dilatation and WPW. The report does not give a transcript accession for this HGVS notation.

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"a de novo BMP2 c.313 C>T (p.R105X) variant in the patient"

Reports this sequence variant in the clinical context described.

BMP2 c.440C>G (p.Ser147Ter)

Gene: BMP2 hgnc:1069 single nucleotide variant

Variant detail: nonsense

A de novo nonsense variant in the single reported patient with phalangeal osteolysis. The cached abstract does not specify the transcript accession.

Show evidence (1 reference)

PMID:40285376 SUPPORT Human Clinical

"Whole-exome sequencing identified a de novo heterozygous truncating variant (c.440C>G; p.Ser147*)"

Reports this sequence variant in the clinical context described.

NM_001200.4:c.217_218dup (p.Val74ProfsTer8)

Gene: BMP2 hgnc:1069 duplication

Variant detail: frameshift

The intragenic frameshift in Individual 4 of the 2025 cohort; Table 1 reports de novo occurrence. The other six individuals had multigene deletions.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"one (Individual 4) had a heterozygous two base pair duplication predicted to lead to a frameshift and a premature stop codon (NM_001200.4): c.217_218dup, p.(Val74Profs*8)"

Reports this sequence variant in the clinical context described.

NM_001200.4:c.231dup (p.Tyr78LeufsTer38)

Gene: BMP2 hgnc:1069 duplication

Variant detail: frameshift

Reported in a family whose proband had short stature, hearing impairment and isolated dextrocardia with situs solitus. The isolated laterality observation does not establish a recurrent genotype-specific phenotype.

Show evidence (1 reference)

PMID:37572998 SUPPORT Human Clinical

"a novel frameshift variant NM_001200.4: c.231dup (p.Tyr78Leufs*38)"

Reports this sequence variant in the clinical context described.

💊

Medical Actions

8

Myringotomy and Ventilation Tube Insertion

Action: myringotomy with ear tube placement Ontology label: Myringotomy with Ear Tube Placement NCIT:C70906

Platform: Surgery

Drainage of persistent middle ear effusion. In the 2025 cohort all four individuals with recurrent secretory otitis media required myringotomy, and all four had conductive hearing loss secondary to the effusion, so this addresses the reversible component of the hearing phenotype.

Mechanism Target:

Eustachian Tube Dysfunction and Middle Ear Effusion — Drains the effusion that is the proximate cause of the conductive loss.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"The conductive hearing impairment detected in four individuals (4/5) in our cohort resulted from repeated secretory otitis media."

Identifies the effusion as the cause of the hearing loss, which is what makes draining it the mechanistically targeted intervention.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Four individuals had recurrent secretory otitis media and needed to go through myringotomy, all of them also had secondary conductive hearing impairment because of secretory otitis media."

Documents the intervention and the indication in this cohort.

Adenoidectomy

Action: adenoidectomy Ontology label: Adenoidectomy NCIT:C51697

Platform: Surgery

Adenoid hypertrophy was treated surgically in three individuals with recurrent secretory otitis media in the 2025 cohort. Its precise causal contribution to their effusions was not tested.

Mechanism Target:

Eustachian Tube Dysfunction and Middle Ear Effusion

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Three of them also had adenoid hypertrophy and underwent adenoidectomy."

Adenoid hypertrophy co-occurred with the effusions in three of the four affected individuals, which is the basis for treating it as part of the same obstructive mechanism. Co-occurrence rather than a demonstrated causal contribution.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Three of them also had adenoid hypertrophy and underwent adenoidectomy."

Documents the intervention in three of the four affected individuals.

Growth Hormone Replacement

Action: growth hormone therapy Ontology label: Pharmacotherapy NCIT:C15986

Agent: recombinant human growth hormone NCIT:C837

Platform: Protein replacement

Growth hormone treatment was associated with improved growth in Individual 5 of the 2025 cohort, who had partial isolated growth hormone deficiency and a multigene deletion. Table 3 also records treatment for short stature in Individual 7 despite normal GH testing. These observations do not establish efficacy for the syndrome as a whole.

Show evidence (2 references)

PMID:39970956 SUPPORT Human Clinical

"Individual 5 had partial, isolated, growth hormone deficiency"

Identifies partial growth hormone deficiency in Individual 5. Table 3 also records GH treatment of Individual 7 despite normal GH testing.

PMID:39970956 SUPPORT Human Clinical

"Individual 5, who presented with partial growth hormone deficiency, responded well to growth hormone treatment."

The reported outcome. A single treated individual, so this is a case observation rather than evidence of efficacy in the syndrome.

Speech and Language Therapy

Action: speech and language therapy Ontology label: Speech Language Therapy NCIT:C159273

Platform: Behavioral / lifestyle

Supports speech, articulation and language development. Hearing and developmental assessment can identify additional needs; normal intelligence should not be assumed solely from the BMP2 diagnosis.

Target Phenotypes: Delayed speech and language development HP:0000750

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Delayed speech, secretory otitis media and conductive hearing loss are common features that require medical attention."

Establishes speech delay as a management target. Cited for the indication; no trial of speech therapy in this disorder has been reported.

Cardiac Radiofrequency Ablation

Action: cardiac radiofrequency ablation Ontology label: Cardiac Radiofrequency Ablation NCIT:C170884

Platform: Surgery

Successful radiofrequency ablation was reported at age 13 for a left-sided accessory pathway in a patient with WPW and an intragenic BMP2 truncating variant. This treats the documented arrhythmia substrate.

Target Phenotypes: Wolff-Parkinson-White syndrome HP:0001716

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"His accessory pathway, which was left sided, was found to have a shortest conducted R–R interval of greater than 250 ms. Radiofrequency ablation was successful."

Documents the accessory pathway and successful ablation in a single patient.

Physical and Occupational Therapy

Action: physical therapy Ontology label: Physical Therapy NCIT:C15302

Platform: Behavioral / lifestyle

Hypotonia gradually improved during the early years of life with physical and occupational therapy in the 2021 reported patient. The uncontrolled observation does not separate treatment effect from developmental change.

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"The hypotonia gradually improved over the first few years of life with occupational and physical therapy."

Reports supportive therapy and the clinical course in one patient.

Mandibular Distraction Osteogenesis

Action: mandibular distraction osteogenesis Ontology label: Orthopedic Surgical Procedure NCIT:C16186

Platform: Surgery

Two individuals with Pierre Robin sequence in the 2017 cohort required mandibular distraction osteogenesis. This is reported clinical management of severe mandibular underdevelopment; the cohort does not quantify comparative efficacy.

Target Phenotypes: Micrognathia HP:0000347

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Human Clinical

"had Pierre Robin sequence and a cleft palate, and two of them required mandibular distraction osteogenesis."

Reports the procedure in two of the three individuals with Pierre Robin sequence.

Surgery for Progressive Scoliosis

Action: surgical correction of scoliosis Ontology label: Orthopedic Surgical Procedure NCIT:C16186

Platform: Surgery

Surgical intervention at age thirteen was reported for progressive thoracic scoliosis in the 2021 patient. The report does not specify the operative technique or a syndrome-specific threshold.

Show evidence (1 reference)

PMID:33247540 SUPPORT Human Clinical

"Other skeletal abnormalities included progressive thoracic scoliosis, which required surgical intervention at 13 years of age."

Documents orthopedic surgical management in the intragenic-variant case.

🔬

Diagnosis

6

Chromosomal microarray (PRESENT)

Detects deletions encompassing BMP2 and defines their genomic extent. Gene content informs interpretation of additional findings, but deletion size alone does not predict their penetrance.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"For larger deletions, validation and segregation were done using array comparative genomic hybridisation"

Array CGH is the method used to confirm and size the deletions in this cohort.

Exome or genome sequencing (PRESENT)

Can identify intragenic BMP2 variants, including truncating, frameshift, splice-altering and selected missense variants. Coverage and variant interpretation matter; low-level parental mosaicism may require targeted assays or another tissue.

Show evidence (1 reference)

PMID:40285376 SUPPORT Human Clinical

"Whole-exome sequencing identified a de novo heterozygous truncating variant (c.440C>G; p.Ser147*) in BMP2."

Documents sequence-level identification of a de novo truncating BMP2 variant; the abstract does not establish a prior negative microarray.

Growth hormone axis evaluation (VARIABLE)

Recommended in the workup of short stature here, because partial isolated growth hormone deficiency has been documented in one individual and responded to replacement. Whether it is part of the syndrome or coincidental is unresolved.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Until then, we suggest that evaluation of growth hormone levels should be included in the medical investigation."

The recommendation, stated with the uncertainty that motivates it.

Audiological surveillance and middle ear examination (PRESENT)

Regular assessment of hearing and of the middle ear, proposed as routine surveillance because effusion and conductive loss are common and treatable.

Show evidence (1 reference)

PMID:39970956 SUPPORT Human Clinical

"Based on our observations, we recommend that evaluation of language development and regular controls of the middle ear are included in the surveillance of these individuals."

The seven-person 2025 cohort explicitly recommends surveillance of middle-ear disease and language development.

Longitudinal skeletal radiography (VARIABLE)

Longitudinal skeletal monitoring was proposed by the authors of the phalangeal osteolysis case report. The published abstract reports detection at age ten but does not provide earlier radiographic comparisons or a validated surveillance interval.

Show evidence (1 reference)

PMID:40285376 SUPPORT Human Clinical

"These findings highlight the necessity of longitudinal skeletal monitoring in BMP2-related conditions"

The recommendation as stated by the reporting authors.

Cardiac imaging and rhythm assessment (VARIABLE)

Echocardiography and electrocardiography characterize structural and rhythm involvement. A patient with bicuspid aortic valve and WPW underwent annual echocardiography that documented progressive aortic dilatation. This is a case-based surveillance example, not a validated universal interval.

Show evidence (2 references)

PMID:33247540 SUPPORT Human Clinical

"The patient was monitored annually with echocardiograms for progression of the cardiovascular involvement. Slow progressive dilation of aortic root and ascending aorta was noted without aortic stenosis and, at most, mild aortic insufficiency"

Documents longitudinal imaging and its findings in the intragenic-variant case.

PMID:33247540 SUPPORT Human Clinical

"an electrocardiogram showed evidence of preexcitation consistent with Wolff–Parkinson–White syndrome (WPW)."

ECG identified pre-excitation in the patient evaluated for palpitations.

📊

Prevalence

1

Worldwide

Cases In Literature Not yet documented

Population prevalence is not established. Published cohorts include 12 individuals in the 2017 defining series, 18 in the 2023 international series, and seven in the 2025 report. These cohort sizes and the 2025 literature subset of 29 individuals are not independent counts to sum: the latter is restricted by genotype and potential confounding diagnoses.

Show evidence (2 references)

PMID:39970956 SUPPORT Human Clinical

"In the literature most individuals (28/29) with BMP2 sequence variants or deletions encompassing only BMP2, and no other genetic variant conflicting interpretation, have no or mild developmental delay"

A selected literature subset used to assess developmental outcomes, not a complete count of all published cases or a population prevalence estimate.

PMID:37125634 SUPPORT Human Clinical

"We used retrospective chart review to examine phenotypes from an international cohort of 18 individuals and compared these with published cases."

Documents the size of the 2023 cohort without establishing a cumulative case count.

⚖️

Clinical Burden

Moderate

Burden varies with skeletal, craniofacial, cardiac and hearing involvement. Reported care includes middle-ear procedures, speech support, dental and craniofacial interventions, scoliosis surgery and cardiac monitoring or ablation. Published series do not establish life expectancy, and normal cognition is not universal across all reported genotypes.

Show evidence (2 references)

PMID:29198724 SUPPORT Human Clinical

"display a consistent distinct phenotype characterized by short stature and skeletal and cardiac anomalies without neurological deficits"

The defining cohort described a multisystem malformation phenotype without reported neurological deficits. This cohort observation does not establish lifelong cognitive or survival outcomes for all affected individuals.

PMID:39970956 SUPPORT Human Clinical

"Delayed speech, secretory otitis media and conductive hearing loss are common features that require medical attention."

Establishes an ongoing, non-trivial care requirement, which is the other half of a moderate rather than mild rating.

🔀

Differential Diagnoses

3

Conditions with similar clinical presentations that must be differentiated from BMP2-Related Short Stature-Facial Dysmorphism-Skeletal Anomalies Syndrome:

Brachydactyly type A2 MONDO:0007216

Overlapping Features Brachydactyly type A2 primarily affects the middle phalanges, especially of the second and fifth digits, and can arise from BMPR1B or GDF5 variants. Two families carried tandem duplications of 5,895 and 5,547 bp approximately 110 kb downstream of BMP2. A homologous wild-type mouse sequence drove a limb reporter, supporting enhancer activity. Increased or ectopic BMP2 expression from the human duplication was proposed, not directly measured. This regional regulatory lesion is distinct from coding BMP2 loss and whole-gene deletion.

Distinguishing Features

Predominantly digital malformations rather than the multisystem BMP2 haploinsufficiency phenotype
A tandem duplication of a downstream regulatory element can underlie BMP2-linked BDA2; BMPR1B and GDF5 are alternative causal genes.

Show evidence (2 references)

PMID:19327734 SUPPORT Human Clinical

"Our results reveal an additional functional mechanism for the pathogenesis of BDA2, which is duplication of a regulatory element that affects the expression of BMP2 in the developing limb."

Human duplications segregated with BDA2. The full paper separately demonstrated limb enhancer activity in mice and proposed, rather than measured, the duplication-induced expression change.

PMID:19327734 SUPPORT Model Organism

"These analyses revealed a specific X-Gal staining in the limb buds and the developing phalanges but not in other parts of the embryos"

The wild-type homologous sequence drove a reporter in transgenic mice. This does not directly measure endogenous BMP2 expression in duplication carriers.

Larger 20p12 contiguous gene deletion syndromes

Overlapping Features Multigene 20p12 deletions can add or modify phenotypes beyond the BMP2-associated core. JAG1 involvement is relevant to Alagille syndrome, and deletions including PROKR2 have been reported with hypopituitarism. Individual contributions and penetrance require assessment rather than assigning every additional feature to a neighboring gene. WPW has also occurred with an intragenic BMP2 truncating variant, so it is not restricted to large deletions.

Distinguishing Features

Deletion boundaries and gene content on chromosomal microarray
Additional findings confined to multigene deletions require separate causal assessment; variable expressivity can occur within a family.

Show evidence (2 references)

PMID:21671386 SUPPORT Human Clinical

"Microdeletion 20p13p12 involving BMP2 is rare and has been implicated in Wolff-Parkinson-White (WPW) syndrome with neurocognitive deficits and with Alagille syndrome when the deletion includes the neighboring JAG1 gene in addition to BMP2."

Names the contiguous-gene phenotypes and ties Alagille syndrome specifically to JAG1 inclusion rather than to BMP2.

PMID:28586151 SUPPORT Human Clinical

"The deletion contained 17 protein coding genes including PROKR2 and BMP2, both of which are expressed during embryological development of the pituitary gland."

A 4.8 Mb deletion in which 17 genes are removed. Cited as the reason hypopituitarism in a deletion patient cannot be attributed to BMP2 dose alone.

🧫

Experimental Models

3

Patient lymphoblast BMP2 splicing assay CELL_LINE

RT-PCR of lymphoblast RNA and sequencing of isolated amplicons identifies aberrant processing of the familial intron 1 splice-acceptor variant.

Organism

Homo sapiens NCBITaxon:9606

Publication

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/

Pathograph links

BMP2 Haploinsufficiency measures fidelity: moderate RT-PCR of lymphoblast RNA and sequencing of isolated amplicons identifies aberrant processing of the familial intron 1 splice-acceptor variant.

Limitations: Non-skeletal cells establish a transcript-processing defect, not the protein dose or signaling consequence in affected embryonic tissues.

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT In Vitro

"Sanger sequencing of gel-purified PCR products revealed that band 4 contained 61 nucleotides of exon 2, whereas band 5 contained only 28 nucleotides from exon 2"

Patient lymphoblast RT-PCR and sequencing identified two additional cryptic splice products. Wild-type and naturally alternatively spliced products were also present; protein abundance and nonsense-mediated decay were not measured.

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT In Vitro

"Sanger sequencing of gel-purified PCR products revealed that band 4 contained 61 nucleotides of exon 2, whereas band 5 contained only 28 nucleotides from exon 2"

Patient lymphoblast RT-PCR and sequencing identified two additional cryptic splice products. Wild-type and naturally alternatively spliced products were also present; protein abundance and nonsense-mediated decay were not measured.

Embryonic head and isolated palate culture rescue OTHER

E13.5 conditional-mutant heads cultured for 24 hours after tongue and mandible removal recover palatal elevation; isolated palatal shelves fuse during 72-hour organ culture.

Organism

Mus musculus NCBITaxon:10090

Publication

PMID:30413887

Pathograph links

Failure of Tongue Descent and Palatal Shelf Elevation perturbs fidelity: moderate E13.5 conditional-mutant heads cultured for 24 hours after tongue and mandible removal recover palatal elevation; isolated palatal shelves fuse during 72-hour organ culture.

Limitations: A mechanical rescue in explants from homozygous conditional-null embryos does not establish every cause of human BMP2-associated clefting.

Show evidence (1 reference)

PMID:30413887 SUPPORT In Vitro

"similar to the wild-type controls, the palatal shelves of mutants were able to elevate in roller culture (Fig. 3 a-d) and to fuse in organ culture (Fig. 3 e, f)."

Rescue after removal of the tongue and mandible supports an extrinsic obstruction to elevation.

Show evidence (1 reference)

PMID:30413887 SUPPORT In Vitro

"similar to the wild-type controls, the palatal shelves of mutants were able to elevate in roller culture (Fig. 3 a-d) and to fuse in organ culture (Fig. 3 e, f)."

Rescue after removal of the tongue and mandible supports an extrinsic obstruction to elevation.

Chick atrioventricular endocardial-myocardial coculture CO_CULTURE

Antisense inhibition of BMP2 suppresses mesenchyme formation in AV endocardium cocultured with myocardium; recombinant BMP2 rescues the effect.

Organism

Gallus gallus NCBITaxon:9031

Publication

PMID:10362015

Pathograph links

Failed Endocardial Cushion Mesenchymal Transition perturbs fidelity: moderate Antisense inhibition of BMP2 suppresses mesenchyme formation in AV endocardium cocultured with myocardium; recombinant BMP2 rescues the effect.

Limitations: This is an avian explant perturbation. Recombinant BMP2 alone did not induce transformation in endothelial monolayers, and patient heterozygosity was not modeled.

Show evidence (1 reference)

PMID:10362015 SUPPORT In Vitro

"Antisense oligodeoxynucleotides to BMP2 inhibited mesenchyme formation in AV endocardium cocultured with associated myocardium. This inhibitory effect was reversed by the addition of recombinant BMP2."

Loss and rescue identify a BMP2 contribution in the coculture system.

Show evidence (1 reference)

PMID:10362015 SUPPORT In Vitro

"Antisense oligodeoxynucleotides to BMP2 inhibited mesenchyme formation in AV endocardium cocultured with associated myocardium. This inhibitory effect was reversed by the addition of recombinant BMP2."

Loss and rescue identify a BMP2 contribution in the coculture system.

🐁

Animal Models

5

Heterozygous Bmp2 knockout mouse

A heterozygous Bmp2-null model supports dosage sensitivity through growth and rib abnormalities. The 2017 study measured the skeleton directly; additional axial and survival findings in the 2009 study depend on its genetic background.

Species

Mouse

Genotype

Bmp2 heterozygous null

Publication

PMID:29198724

Pathograph links

BMP2 Haploinsufficiency recapitulates fidelity: high observes: organism Loss of one Bmp2 allele reproduces reduced body length and rib abnormalities. Patient ligand concentrations were not measured.

Limitations: The report describes phenotypic similarity for growth and skeletal features; it does not claim the craniofacial gestalt or the cardiac anomalies are reproduced, so the model is not established as covering those arms.

Readouts

Axial skeletal defects in Bmp2 heterozygous adults

Direction: INCREASED

Interpretation: The 2009 study found defects in dorsal fusion of cervical vertebrae in 3/9 and defects of the 13th rib in 7/9 Bmp2 heterozygotes. The cervical finding is failure of dorsal fusion, not excessive fusion between vertebrae. These are cohort-specific mouse observations.

Show evidence (1 reference)

PMID:19116164 SUPPORT Model Organism

"Notably, we detected identical defects in dorsal fusion of one or more cervical vertebrae (Fig. 1A and B) as well as defects in formation of the 13th rib (Fig. 1C and D) in 33% and 77%, respectively, of all Bmp2−/+ skeletons analyzed (n = 9)."

The measurement itself, in Bmp2 heterozygotes rather than the Bmp4 animals named earlier in the same passage as prior art.

Reduced body length with preserved femur and tibia lengths

Direction: DECREASED

Interpretation: The 2017 heterozygote comparison found reduced total body length without shorter femora or tibiae. It supports the growth phenotype without demonstrating generalized long-bone growth-plate failure.

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Model Organism

"We observed that the body of heterozygous ... mice was significantly shorter than that of wild-type mice, consistent with short stature in human individuals, but the two groups of mice showed no differences in femur or tibia length"

Direct morphometry distinguishes total body length from long-bone length.

Preserved femoral mechanical properties

Direction: UNCHANGED

Interpretation: Despite reduced bone mineral content and volume, three-point bending did not detect impaired femoral mechanics in the 2017 heterozygotes. This limits inference of universal fragility from complete conditional-null mice.

Show evidence (1 reference)

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/ SUPPORT Model Organism

"We did not observe any significant differences in maximum load, yield load, work to failure, or stiffness between the two groups"

Negative mechanical testing result in Bmp2 heterozygotes compared with wild-type littermates.

Show evidence (1 reference)

PMID:29198724 SUPPORT Model Organism

"Additionally, we observed similarity to the human phenotype of short stature and skeletal anomalies in a heterozygous Bmp2-knockout mouse model, suggesting that haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions..."

Attests that this model is informative for the haploinsufficiency node, by the authors' own comparison with the human phenotype.

Show evidence (1 reference)

PMID:29198724 SUPPORT Model Organism

"Additionally, we observed similarity to the human phenotype of short stature and skeletal anomalies in a heterozygous Bmp2-knockout mouse model, suggesting that haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions..."

The comparison that makes this the reference model for the disorder.

Wnt1-Cre;Bmp2 flox/flox cranial neural crest conditional knockout mouse

Tissue-specific homozygous deletion of Bmp2 in cranial neural crest, generated explicitly to model the human Pierre Robin sequence caused by BMP2 haploinsufficiency.

Species

Mouse

Genotype

Wnt1-Cre;Bmp2 fl/fl

Publication

PMID:30413887

Pathograph links

Impaired Cranial Neural Crest Osteogenic Differentiation recapitulates fidelity: moderate observes: cellular Reduced proliferation and osteogenic differentiation of mandibular progenitors is measured directly in this model.

Limitations: Homozygous conditional loss in one lineage, not a heterozygous whole-organism halving, so it demonstrates the requirement rather than the sufficiency of a halved dose. The mutants die at birth, which is far more severe than the human disorder.

Show evidence (1 reference)

PMID:30413887 SUPPORT Model Organism

"Further studies revealed obvious reduction in cell proliferation and differentiation of osteogenic progenitors in the mandible of the mutants, attributing to the micrognathia phenotype."

The measured progenitor defect is what makes this model informative for the cranial-neural-crest osteogenic node.

Craniofacial Skeletal Hypoplasia partially recapitulates fidelity: moderate observes: tissue Micrognathia, cleft palate, zygomatic and mandibular hypoplasia are all reproduced.

Limitations: Complete, lineage-restricted loss produces neonatal lethality and fully penetrant cleft palate. Species and genotype differences prevent a quantitative prediction of human heterozygous severity.

Show evidence (1 reference)

PMID:30413887 SUPPORT Model Organism

"Lateral views of 3D reconstructions from microCT scans further confirmed severe craniofacial bone defects in mutant mice"

Imaging confirmation of the craniofacial skeletal hypoplasia this link is cited for, rather than gross inspection alone.

Show evidence (1 reference)

PMID:30413887 SUPPORT Model Organism

"Mutant mice exhibit severe PRS with a significantly reduced size of craniofacial bones, cleft palate, malformed tongue and micrognathia."

The phenotype that makes this model informative for the craniofacial arm.

AV myocardial Bmp2 conditional knockout mouse

Inactivation of Bmp2 in the atrioventricular myocardium, which is the source of the signal that induces endocardial transformation.

Species

Mouse

Genotype

Bmp2 conditional null in atrioventricular myocardium

Publication

PMID:16314491

Pathograph links

Failed Endocardial Cushion Mesenchymal Transition recapitulates fidelity: moderate observes: tissue Loss of cushion EMT, of cardiac jelly, and of AV myocardial patterning.

Limitations: Complete tissue-restricted loss rather than a halved organism-wide dose, so it identifies the required signal without establishing that heterozygosity alone produces the human septal defects. It also reproduces no other arm of the syndrome.

Show evidence (1 reference)

PMID:16314491 SUPPORT Model Organism

"Bmp2 is required for myocardial expression of Has2, a crucial component of the cardiac jelly matrix."

A specific molecular readout measured in this model, grounding the cushion-formation claim in more than gross morphology.

Show evidence (1 reference)

PMID:16314491 SUPPORT Model Organism

"Here, we inactivated bone morphogenetic protein 2 (Bmp2) in the AV myocardium of mice. We show that Bmp2 has three functions in the AV canal: to enhance formation of the cardiac jelly, to induce endocardial EMT and to pattern the AV myocardium."

The model and its three measured cardiac phenotypes.

Limb-conditional Bmp2 knockout mouse

Limb-restricted Bmp2 deletion permits early bone formation but produces spontaneous non-healing fractures. The observed postnatal phenotype does not imply that deletion was induced only after the skeleton formed.

Species

Mouse

Genotype

Bmp2 conditional null restricted to the limb skeleton

Publication

PMID:17099713

Pathograph links

Deficient Skeletal Repair and Bone Homeostasis recapitulates fidelity: low observes: tissue Spontaneous non-healing fractures establish BMP2 as required to initiate bone repair.

Limitations: Homozygous limb-restricted loss, and the human phenotype it is invoked for - phalangeal osteolysis - has been reported in a single patient. The model shows that a repair requirement exists, not that a halved human dose breaches it.

Show evidence (1 reference)

PMID:17099713 SUPPORT Model Organism

"Mice lacking the ability to produce BMP2 in their limb bones have spontaneous fractures that do not resolve with time."

The observed skeletal-maintenance failure this link is cited for.

Show evidence (1 reference)

PMID:17099713 SUPPORT Model Organism

"Here we demonstrate that BMP2 is a necessary component of the signaling cascade that governs fracture repair."

The finding this model contributes, distinct from the developmental phenotypes of the other models here.

Zebrafish bmp2b ventralization assay for patient missense alleles

Not a disease model but a variant-function assay: each patient missense allele is tested for its ability to support bmp2b-driven embryonic dorsoventral patterning. Its purpose is allele interpretation, which is why it is linked to the haploinsufficiency node rather than to any phenotype.

Species

Zebrafish

Genotype

patient-derived BMP2 missense alleles assayed against bmp2b function

Publication

PMID:37125634

Pathograph links

BMP2 Haploinsufficiency measures fidelity: moderate observes: organism Reads out whether a given missense allele retains BMP2 function, and so whether it belongs in the same loss-of-function class as the truncating alleles.

Limitations: The readout is embryonic ventralization in a fish, which is not a craniofacial, skeletal or cardiac phenotype and shares no tissue context with the human disease. It measures whether the protein works at all, not how a halved dose behaves in the affected human tissues.

Show evidence (1 reference)

PMID:37125634 SUPPORT Model Organism

"Missense variants modeled in zebrafish resulted in loss of protein function."

The assay result that places patient missense alleles in the loss-of-function class.

Show evidence (1 reference)

PMID:37125634 SUPPORT Model Organism

"Patient-derived missense variants were modeled in zebrafish to examine their effect on the ability of bmp2b to promote embryonic ventralization."

States what the assay is and what it reads out.

{ }

Source YAML

click to show

name: BMP2-Related Short Stature-Facial Dysmorphism-Skeletal Anomalies Syndrome
creation_date: "2026-09-05T00:00:00Z"
category: Mendelian
synonyms:
- SSFSC1
- short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 1
- BMP2 haploinsufficiency
- 20p12.3 microdeletion syndrome involving BMP2
description: >-
  A rare autosomal dominant developmental disorder caused by heterozygous loss-of-function BMP2 variants
  or deletions encompassing BMP2. Short stature, craniofacial differences, digital and axial skeletal
  abnormalities, and variable cardiac involvement form the core spectrum. Normal stature can occur. Conductive
  hearing impairment and speech delay are also reported. Human genetic findings and heterozygous mouse
  models support haploinsufficiency; an exact reduction in secreted ligand has not been measured across
  patient alleles. This entity is distinct from recessive SCUBE3-related SSFSC2 and from BMP2 regulatory-duplication-associated
  brachydactyly type A2.
disease_term:
  preferred_term: short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 1
  term:
    id: MONDO:0100297
    label: short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 1
parents:
- Autosomal dominant disease
- Skeletal dysplasia
classifications:
  harrisons_chapter:
  - classification_value: GENETICS_ENVIRONMENT_DISEASE
prevalence:
- population: Worldwide
  measure_type: CASES_IN_LITERATURE
  prevalence_class: NOT_YET_DOCUMENTED
  notes: >-
    Population prevalence is not established. Published cohorts include 12 individuals in the 2017 defining
    series, 18 in the 2023 international series, and seven in the 2025 report. These cohort sizes and
    the 2025 literature subset of 29 individuals are not independent counts to sum: the latter is restricted
    by genotype and potential confounding diagnoses.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In the literature most individuals (28/29) with BMP2 sequence variants or deletions encompassing only BMP2, and no other genetic variant conflicting interpretation, have no or mild developmental delay"
    explanation: >-
      A selected literature subset used to assess developmental outcomes, not a complete count of all
      published cases or a population prevalence estimate.
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We used retrospective chart review to examine phenotypes from an international cohort of 18 individuals and compared these with published cases."
    explanation: >-
      Documents the size of the 2023 cohort without establishing a cumulative case count.
inheritance:
- name: Autosomal dominant
  inheritance_term:
    preferred_term: Autosomal dominant inheritance
    term:
      id: HP:0000006
      label: Autosomal dominant inheritance
  description: >-
    Heterozygous BMP2 loss-of-function variants and deletions may arise de novo or be inherited. In the
    2017 family with two affected sisters, variant-specific assays detected somatic mosaicism in their
    clinically unaffected father; transmission to both daughters also establishes germline involvement.
    Routine blood sequencing did not detect the mosaic variant in that father.
  evidence:
  - reference: PMID:29198724
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "De novo occurrence and autosomal-dominant inheritance of variants, including paternal mosaicism in two affected sisters who inherited a BMP2 splice-altering variant, were observed across all reported families."
    explanation: >-
      Establishes dominant transmission and documents paternal mosaicism, which
      matters for recurrence counselling in apparently de novo families.
genetic:
- name: BMP2
  gene_term:
    preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  relationship_type: CAUSATIVE
  variant_origin: GERMLINE
  notes: >-
    BMP2 at 20p12.3 encodes a secreted ligand of the TGF-beta superfamily. Reported disease-associated
    alleles include truncating, frameshift, splice-altering and initiation-codon variants, whole-gene
    deletions, and functionally assessed missense variants. The shared phenotype of intragenic variants,
    deletions and heterozygous knockout mice supports haploinsufficiency. This does not establish that
    every BMP2 missense variant is pathogenic or that every truncating allele undergoes nonsense-mediated
    decay. The 2017 study did not experimentally demonstrate nonsense-mediated decay. Deletion boundaries
    and additional variants matter when interpreting findings beyond the core phenotype.
  evidence:
  - reference: PMID:29198724
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Here, we report a cranioskeletal phenotype due to monoallelic truncating and frameshift BMP2 variants and deletions in 12 individuals from eight unrelated families that share features of short stature, a recognizable craniofacial gestalt, skeletal anomalies, and congenital heart disease."
    explanation: >-
      The defining series, establishing that truncating variants and deletions
      produce one shared phenotype.
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "One individual had a novel frameshift variant in BMP2, and six individuals had 1.3-3.7 Mb microdeletions, including BMP2."
    explanation: >-
      Documents the two allele classes side by side in one cohort and gives the
      deletion size range.
  - reference: PMID:40285376
    reference_title: "Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Whole-exome sequencing identified a de novo heterozygous truncating variant (c.440C>G; p.Ser147*) in BMP2."
    explanation: >-
      A representative de novo nonsense allele, on the reference transcript used
      across the literature.
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We sought to expand the phenotypic spectrum and highlight phenotypes of patients harboring monoallelic missense variants in BMP2."
    explanation: >-
      Establishes monoallelic missense variants as a disease-causing allele
      class in their own right, which the earlier truncating-and-deletion
      series did not cover. The functional evidence that these are
      loss-of-function alleles is a separate, zebrafish-based claim and is
      graded separately below.
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Missense variants modeled in zebrafish resulted in loss of protein function."
    explanation: >-
      The functional result that puts missense alleles in the same
      loss-of-function mechanism as the truncating ones rather than in a
      separate one.
pathophysiology:
- name: BMP2 Haploinsufficiency
  description: >-
    Loss of one functional BMP2 allele is the principal model for this disorder. Overlapping human phenotypes
    with intragenic variants and deletions, together with growth and rib abnormalities in heterozygous
    knockout mice, support dosage sensitivity. These observations do not quantify secreted ligand in patients
    or exclude other effects of individual mutant proteins.
  biological_scale: MOLECULAR
  genes:
  - preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  molecular_functions:
  - preferred_term: BMP2 growth factor activity
    modifier: DECREASED
    term:
      id: GO:0008083
      label: growth factor activity
  downstream:
  - target: Reduced Canonical BMP-SMAD Signalling Output
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Complete cranial neural crest Bmp2 deletion reduces mandibular SMAD phosphorylation. Reduced signaling
      is a proposed consequence of human haploinsufficiency; the dose-response and intervening receptor
      activity were not measured in patients.
    evidence:
    - reference: PMID:30413887
      reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals.
      explanation: >-
        Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone
        of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement
        in heterozygous patients.
  - target: Reduced Noncanonical p38 Signalling Output
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      The same mouse deletion reduces mandibular p38 phosphorylation; relevance to human heterozygous
      loss is inferred.
    evidence:
    - reference: PMID:30413887
      reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals.
      explanation: >-
        Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone
        of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement
        in heterozygous patients.
  - target: Reduced Osteogenic Output of Skeletal Progenitors
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      BMP2 and BMP4 jointly support osteoblast maturation in limb mesenchyme. The combined-knockout experiments
      establish a pathway requirement, not the magnitude of a human heterozygous BMP2 defect.
  - target: Failed Endocardial Cushion Mesenchymal Transition
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Myocardial Bmp2 is necessary for cushion induction in conditional-null mice. An equivalent defect
      has not been demonstrated in human BMP2 heterozygotes.
  - target: Deficient Skeletal Repair and Bone Homeostasis
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Complete limb-conditional Bmp2 loss impairs fracture repair. A repair defect from a single defective
      human allele remains unproven.
  - target: Reduced Cranial Neural Crest Chondrogenic Progenitors
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Complete neural crest Bmp2 deletion reduces Meckel cartilage progenitor proliferation and Sox9 expression;
      the human dosage threshold is unknown.
  - target: Wolff-Parkinson-White syndrome
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Pre-excitation has been reported with intragenic BMP2 loss and deletions. The conduction-system
      mechanism is unresolved and is not established by cardiac cushion experiments.
  evidence:
  - reference: PMID:29198724
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Additionally, we observed similarity to the human phenotype of short stature and skeletal anomalies in a heterozygous Bmp2-knockout mouse model, suggesting that haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions encompassing BMP2."
    explanation: >-
      The heterozygous knockout phenotype supports haploinsufficiency; it does not by itself exclude additional
      effects of individual human alleles.
  - reference: PMID:19116164
    reference_title: "Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Whereas mice lacking a single copy of Bmp2 or Bmp4 are viable and have subtle developmental defects, compound mutants show embryonic and postnatal lethality due to defects in multiple organ systems including the allantois, placental vasculature, ventral body wall, skeleton, eye and heart."
    explanation: >-
      Bmp2/Bmp4 interactions demonstrate dose sensitivity in mice. Single Bmp2 heterozygotes have skeletal
      defects, but survival and severity depend on background; the full text reports hydrocephalus and
      loss of some heterozygotes on C57BL/6J. These models do not establish human viability or severity
      thresholds.
- name: Reduced Canonical BMP-SMAD Signalling Output
  description: >-
    Canonical BMP pathway activity is reduced in mandibular bone and Meckel cartilage after complete Bmp2
    deletion in the mouse cranial neural crest lineage, measured by pSmad1/5/8 staining. This provides
    a mechanistic model for BMP2-related craniofacial disease. Signaling was not measured across affected
    human tissues, and compensation by other BMP ligands is tissue-dependent.
  biological_scale: MOLECULAR
  biological_processes:
  - preferred_term: BMP signaling pathway
    modifier: DECREASED
    term:
      id: GO:0030509
      label: BMP signaling pathway
  - preferred_term: SMAD protein signal transduction
    modifier: DECREASED
    term:
      id: GO:0060395
      label: SMAD protein signal transduction
  downstream:
  - target: Impaired Cranial Neural Crest Osteogenic Differentiation
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Reduced SMAD phosphorylation accompanies reduced osteogenic progenitors in the conditional mouse
      mutant. The experiment does not isolate SMAD-dependent mediation from the concurrent reduction in
      p38 activity.
    evidence:
    - reference: PMID:30413887
      reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals.
      explanation: >-
        Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone
        of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement
        in heterozygous patients.
  evidence:
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals.
    explanation: >-
      Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone
      of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement in
      heterozygous patients.
  mechanism_confidence: PROVISIONAL
- name: Reduced Noncanonical p38 Signalling Output
  description: >-
    Phosphorylated p38 is reduced in the mandibular bone of cranial neural crest Bmp2 conditional-null
    mice alongside reduced canonical SMAD activity. The relative contributions of the two pathways to
    the progenitor defect have not been separated in this model.
  biological_scale: MOLECULAR
  biological_processes:
  - preferred_term: p38 MAPK cascade
    modifier: DECREASED
    term:
      id: GO:0038066
      label: p38MAPK cascade
  downstream:
  - target: Impaired Cranial Neural Crest Osteogenic Differentiation
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Reduced p38 activity and progenitor proliferation coexist after Bmp2 deletion; pathway-specific
      mediation remains unresolved.
  evidence:
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: As shown in Fig. 6 (a-d), the mutant mandibular bone exhibits reduced pSmad1/5/8 and pp38 signals.
    explanation: >-
      Immunostaining directly demonstrates reduced canonical and p38 signaling in the mandibular bone
      of Wnt1-Cre;Bmp2 flox/flox embryos. This is complete lineage-specific loss, not a measurement in
      heterozygous patients.
  mechanism_confidence: PROVISIONAL
- name: Impaired Cranial Neural Crest Osteogenic Differentiation
  description: >-
    In Wnt1-Cre;Bmp2 flox/flox mice, cranial-neural-crest-derived mandibular mesenchyme has a reduced
    Sp7-positive osteogenic progenitor domain from E12.5 to E16.5. Reduced proliferation precedes the
    morphological mandibular defect. These observations support a developmental requirement for BMP2,
    without establishing a quantitative human heterozygous effect.
  biological_scale: CELLULAR
  conforms_to: "pharyngeal_arch_patterning_serial_homology#Cranial Neural Crest and Pharyngeal Arch Program Perturbation"
  cell_types:
  - preferred_term: osteoblast
    term:
      id: CL:0000062
      label: osteoblast
  biological_processes:
  - preferred_term: neural crest cell development
    modifier: ABNORMAL
    term:
      id: GO:0014032
      label: neural crest cell development
  - preferred_term: osteoblast differentiation
    modifier: DECREASED
    term:
      id: GO:0001649
      label: osteoblast differentiation
  downstream:
  - target: Craniofacial Skeletal Hypoplasia
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:30413887
      reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Further studies revealed obvious reduction in cell proliferation and differentiation of osteogenic progenitors in the mandible of the mutants, attributing to the micrognathia phenotype."
      explanation: >-
        The authors attribute mandibular hypoplasia to reduced progenitor proliferation and differentiation
        in the conditional-null mouse. Its effect size cannot be translated quantitatively to human heterozygotes.
  evidence:
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: We observed that the domain expressing Sp7, a molecular marker for osteogenic progenitors, is reduced throughout this period in Wnt1-Cre;Bmp2f/f mice compared to that in wild-type controls
    explanation: >-
      The Sp7 expression domain was assessed from E12.5 to E16.5, directly supporting the osteogenic progenitor
      defect.
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: the ratio of cell proliferation in the mandible of Wnt1-Cre;Bmp2f/f embryos was significantly reduced
    explanation: >-
      PHH3 staining identified reduced proliferation before the morphological defect.
  notes: >-
    The module mapping concerns neural crest skeletogenesis; arch-identity transformation was not demonstrated.
    The affected progenitors are post-migratory neural-crest-derived mesenchyme, so the migratory cranial
    neural crest cell binding is not used.
  mechanism_confidence: PROVISIONAL
- name: Reduced Cranial Neural Crest Chondrogenic Progenitors
  description: >-
    Complete Bmp2 loss in the mouse cranial neural crest lineage reduces Sox9 expression and proliferation
    in Meckel cartilage. The smaller transient cartilaginous support accompanies mandibular hypoplasia.
    This lineage-specific finding cannot be replaced by results from limb mesenchyme, where other BMP
    ligands can sustain much of chondrogenesis.
  biological_scale: CELLULAR
  cell_types:
  - preferred_term: chondrocyte
    term:
      id: CL:0000138
      label: chondrocyte
  downstream:
  - target: Craniofacial Skeletal Hypoplasia
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Reduced Meckel cartilage and osteogenic progenitors both occur in the mutant mandible; their separate
      causal contributions to bone hypoplasia were not isolated.
  evidence:
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: We found that both the expression area and the intensity of Sox9 are significantly reduced
    explanation: >-
      Sox9 staining supports the chondrogenic defect in Meckel cartilage of conditional-null embryos.
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: These results show that a decreased ratio of cell proliferation leads to reduction of osteogenic and chondrogenic progenitor cells and is responsible for the formation of smaller mandible in the mutants
    explanation: >-
      The authors connect reduced progenitor proliferation to the smaller mandible in this model.
  mechanism_confidence: PROVISIONAL
- name: Craniofacial Skeletal Hypoplasia
  description: >-
    Craniofacial skeletal underdevelopment includes mandibular and midfacial hypoplasia. Neural crest
    Bmp2 conditional-null mice show approximately 40% lower zygomatic volume and 10% shorter mandibular
    length. These model-specific measurements do not predict the magnitude of the human phenotype.
  biological_scale: TISSUE
  conforms_to: "pharyngeal_arch_patterning_serial_homology#Serially Homologous Craniofacial Malformation Across Arch Derivatives"
  biological_processes:
  - preferred_term: face morphogenesis
    modifier: ABNORMAL
    term:
      id: GO:0060325
      label: face morphogenesis
  - preferred_term: embryonic cranial skeleton morphogenesis
    modifier: ABNORMAL
    term:
      id: GO:0048701
      label: embryonic cranial skeleton morphogenesis
  downstream:
  - target: Midface retrusion
    causal_link_type: DIRECT
  - target: Micrognathia
    causal_link_type: DIRECT
  - target: Dental crowding
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Reduced jaw size is a plausible contributor; an independent dental developmental contribution has
      not been excluded.
  - target: Failure of Tongue Descent and Palatal Shelf Elevation
    causal_link_type: DIRECT
    description: >-
      A mandible too small to accommodate the tongue holds it high, where it
      obstructs the palatal shelves.
    evidence:
    - reference: PMID:30413887
      reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
      supports: SUPPORT
      evidence_source: IN_VITRO
      snippet: "These results demonstrated that the failure of palatal shelf elevation in embryo lacking Bmp2 in CNC-derived mesenchyme is due to the steric hindrance of the higher tongue."
      explanation: >-
        Attributes the elevation failure to steric hindrance by the tongue,
        which is this edge. Established in a homozygous cranial-neural-crest
        conditional mutant, not in the heterozygote that matches the human
        disease.
  - target: Eustachian Tube Dysfunction and Middle Ear Effusion
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Craniofacial anatomy is a proposed contributor to recurrent effusions, but the anatomical pathway
      has not been demonstrated specifically in this disorder.
  evidence:
  - reference: PMID:30413887
    reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Lateral views of 3D reconstructions from microCT scans further confirmed severe craniofacial bone defects in mutant mice, including a ~ 40% reduction in the zygomatic volume and a ~ 10% reduction in the length of the mandibular bone with a missing coronoid process"
    explanation: >-
      MicroCT quantifies hypoplasia in two craniofacial skeletal elements of conditional-null mice; these
      are not human effect-size estimates.
- name: Failure of Tongue Descent and Palatal Shelf Elevation
  description: >-
    In the neural crest Bmp2 conditional-null mouse, a small mandible prevents tongue descent and mechanically
    obstructs palatal shelf elevation. Removing the mandible and tongue permits elevation in embryonic
    head culture, and isolated shelves fuse in organ culture. Tongue volume, myogenic differentiation
    and palatal proliferation were preserved. Palatal BMP signaling was largely maintained, although posterior
    nasal-side pSmad1/5/8 was reduced; compensation by BMP4/BMP7 was proposed. The rescue supports a mechanical
    contribution without proving that all human BMP2-associated clefts follow this route.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: roof of mouth development
    modifier: ABNORMAL
    term:
      id: GO:0060021
      label: roof of mouth development
  downstream:
  - target: Cleft palate
    causal_link_type: DIRECT
  - target: Pierre-Robin sequence
    causal_link_type: DIRECT
  evidence:
  - reference: PMID:30413887
    reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Palate clefting is caused by the undescended tongue that prevents palatal shelf elevation."
    explanation: >-
      Describes the tongue-position mechanism in the conditional-null mouse.
  - reference: PMID:30413887
    reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
    supports: REFUTE
    evidence_source: IN_VITRO
    snippet: "Bmp2 itself is not an intrinsic regulator of palatal shelf elevation and fusion."
    explanation: >-
      Cultured mutant heads and palatal shelves retain elevation and fusion capacity after removal of
      the obstruction. This refutes an intrinsic failure of those processes under the tested culture conditions.
  - reference: PMID:30413887
    reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
    supports: REFUTE
    evidence_source: MODEL_ORGANISM
    snippet: "Our results demonstrate that, although Bmp2 is inactivated in CNC-derived mesenchymal tissues, the activities of BMP signaling in the mutant palate appear largely unaffected, most likely attributing to the functional redundancy by Bmp4 and Bmp7."
    explanation: >-
      Most palatal signaling persisted, but the full text reports reduced posterior nasal-side pSmad1/5/8.
      Redundancy was inferred rather than directly tested by combined deletion in this experiment.
  - reference: PMID:21671386
    reference_title: "Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Clinical features were significant for cleft palate and facial dysmorphism in all three patients, including Pierre-Robin sequence in two."
    explanation: >-
      The human counterpart, in patients whose only deleted gene was BMP2 in two
      of three cases.
- name: Reduced Osteogenic Output of Skeletal Progenitors
  description: >-
    In Prx1-Cre limb mesenchyme, combined deletion of Bmp2 and Bmp4 allows an initial bone collar but
    prevents sustained osteoblast maturation and trabecular or cortical bone formation. Osterix expression
    declines after birth. Loss of Bmp2 alone largely preserves early limb skeletal differentiation in
    this experiment, showing that the combined-knockout result is not a direct demonstration of the human
    monoallelic defect. Chondrogenic requirements differ by lineage and developmental stage.
  biological_scale: CELLULAR
  cell_types:
  - preferred_term: chondrocyte
    term:
      id: CL:0000138
      label: chondrocyte
  - preferred_term: osteoblast
    term:
      id: CL:0000062
      label: osteoblast
  biological_processes:
  - preferred_term: osteoblast differentiation
    modifier: DECREASED
    term:
      id: GO:0001649
      label: osteoblast differentiation
  downstream:
  - target: Impaired Endochondral Bone Growth
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Failed osteoblast maturation interrupts endochondral bone formation in combined Bmp2/Bmp4 limb mutants.
      Its contribution to human BMP2 haploinsufficiency is inferred.
  evidence:
  - reference: PMID:17194222
    reference_title: "Genetic analysis of the roles of BMP2, BMP4, and BMP7 in limb patterning and skeletogenesis."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: MODEL_ORGANISM
    snippet: "In contrast, we find that the loss of both BMP2 and BMP4 results in a severe impairment of osteogenesis."
    explanation: >-
      Combined Bmp2/Bmp4 loss impairs completion of osteoblast differentiation; Bmp2 loss alone did not
      produce this severe limb phenotype.
  - reference: PMID:17194222
    reference_title: "Genetic analysis of the roles of BMP2, BMP4, and BMP7 in limb patterning and skeletogenesis."
    supports: REFUTE
    evidence_source: MODEL_ORGANISM
    snippet: "However, in the condensations that do form, subsequent chondrogenic differentiation proceeds normally even in the absence of BMP2 and BMP7 or BMP2 and BMP4."
    explanation: >-
      Chondrogenic differentiation continues in condensations that form in these limb-mesenchyme mutants,
      with a delay described in the full text. This does not refute BMP2-dependent chondrogenesis in other
      lineages, including Meckel cartilage.
  mechanism_confidence: PROVISIONAL
- name: Impaired Endochondral Bone Growth
  description: >-
    Disrupted endochondral ossification is a plausible contributor to the growth and digital phenotype,
    supported by combined Bmp2/Bmp4 limb-mutant experiments. Normal growth hormone testing in some patients
    does not localize the defect specifically to the growth plate. In the heterozygous Bmp2 mouse studied
    in 2017, total body length was reduced but femoral and tibial lengths were unchanged.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: endochondral ossification
    modifier: DECREASED
    term:
      id: GO:0001958
      label: endochondral ossification
  - preferred_term: growth plate cartilage development
    modifier: DECREASED
    term:
      id: GO:0003417
      label: growth plate cartilage development
  downstream:
  - target: Short stature
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      A developmental skeletal contribution is plausible, but the precise cellular sequence in human heterozygotes
      is unresolved.
  - target: Brachydactyly
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      A developmental skeletal contribution is plausible, but the precise cellular sequence in human heterozygotes
      is unresolved.
  - target: Short toe
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      A developmental skeletal contribution is plausible, but the precise cellular sequence in human heterozygotes
      is unresolved.
  evidence:
  - reference: PMID:17194222
    reference_title: Genetic analysis of the roles of BMP2, BMP4, and BMP7 in limb patterning and skeletogenesis.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: In contrast, we find that the loss of both BMP2 and BMP4 results in a severe impairment of osteogenesis.
    explanation: >-
      The full text localizes failed osteoblast maturation to endochondral bone formation in compound
      limb mutants; it does not establish a primary growth-plate lesion in patients.
    directness: INDIRECT
  mechanism_confidence: HYPOTHETICAL
- name: Deficient Skeletal Repair and Bone Homeostasis
  description: >-
    Limb-conditional Bmp2-null mice develop spontaneous fractures that fail to heal, demonstrating a requirement
    for BMP2 in fracture repair. This provides a candidate mechanism for skeletal maintenance abnormalities,
    but neither a repair defect in human heterozygotes nor a causal connection to the single reported
    phalangeal osteolysis case has been established.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: bone remodeling
    modifier: ABNORMAL
    term:
      id: GO:0046849
      label: bone remodeling
  downstream:
  - target: Phalangeal osteolysis
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Provisional cross-species hypothesis: non-healing fractures after complete mouse limb Bmp2 loss
      and osteolysis in one heterozygous patient are distinct observations, without a demonstrated causal
      bridge.
  evidence:
  - reference: PMID:17099713
    reference_title: "BMP2 activity, although dispensable for bone formation, is required for the initiation of fracture healing."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Mice lacking the ability to produce BMP2 in their limb bones have spontaneous fractures that do not resolve with time."
    explanation: >-
      Separates a postnatal bone-maintenance requirement for BMP2 from its
      developmental one. Note this is the homozygous limb-conditional null, not
      the heterozygote, so it establishes that the requirement exists rather
      than that a halved dose is enough to breach it.
  notes: >-
    The fracture-repair experiment uses complete limb-restricted loss. Human phalangeal osteolysis has
    been reported in one case and does not establish a general fracture-healing phenotype.
  mechanism_confidence: HYPOTHETICAL
- name: Failed Endocardial Cushion Mesenchymal Transition
  description: >-
    Myocardial Bmp2 is required for atrioventricular cardiac jelly formation, induction of endocardial
    epithelial-to-mesenchymal transition and AV myocardial patterning in conditional-null mice. This identifies
    one developmental pathway relevant to congenital cardiac malformations, without establishing that
    human heterozygosity causes cushion failure or explaining every reported cardiac feature.
  biological_scale: CELLULAR
  cell_types:
  - preferred_term: endocardial cell
    term:
      id: CL:0002350
      label: endocardial cell
  biological_processes:
  - preferred_term: epithelial to mesenchymal transition involved in endocardial cushion formation
    modifier: DECREASED
    term:
      id: GO:0003198
      label: epithelial to mesenchymal transition involved in endocardial cushion formation
  downstream:
  - target: Altered Cardiac Development
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Failure of cushion induction can disrupt AV septation and valves. The experiments do not explain
      human semilunar valve anomalies, aortopathy or electrical conduction abnormalities.
  evidence:
  - reference: PMID:16314491
    reference_title: "Bmp2 is essential for cardiac cushion epithelial-mesenchymal transition and myocardial patterning."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "We show that Bmp2 has three functions in the AV canal: to enhance formation of the cardiac jelly, to induce endocardial EMT and to pattern the AV myocardium."
    explanation: >-
      Assigns cushion induction to Bmp2 specifically, in the myocardial
      compartment that signals to the endocardium. Homozygous conditional
      inactivation, so it shows the signal is required rather than that halving
      it produces the human septal defects.
  - reference: PMID:10362015
    reference_title: "Bone morphogenetic protein-2 acts synergistically with transforming growth factor-beta3 during endothelial-mesenchymal transformation in the developing chick heart."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Antisense oligodeoxynucleotides to BMP2 inhibited mesenchyme formation in AV endocardium cocultured with associated myocardium. This inhibitory effect was reversed by the addition of recombinant BMP2."
    explanation: >-
      A loss-and-rescue experiment in explant culture, which is the cleanest
      demonstration that the BMP2 signal itself is what drives cushion
      mesenchyme formation. Independent of the mouse genetics and of a
      transgenic background.
  - reference: PMID:10362015
    reference_title: "Bone morphogenetic protein-2 acts synergistically with transforming growth factor-beta3 during endothelial-mesenchymal transformation in the developing chick heart."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: IN_VITRO
    snippet: "However, BMP2 enhanced the TGFbeta-induced initial phenotypic changes associated with endothelial-mesenchymal transformation."
    explanation: >-
      In cultured chick AV endothelial cells, BMP2 enhanced TGF-beta-induced changes but was insufficient
      alone. This co-signal requirement does not establish the reason for incomplete human penetrance.
  mechanism_confidence: PROVISIONAL
- name: Altered Cardiac Development
  description: >-
    Human BMP2 variants and deletions are associated with a variable cardiac spectrum including septal,
    outflow and valve abnormalities. Bicuspid aortic valve with progressive aortic dilatation has been
    described with an intragenic truncating variant. Mouse myocardial conditional and Bmp2/Bmp4 compound
    mutants demonstrate developmental requirements, but the pathways underlying individual human lesion
    classes remain unresolved.
  biological_scale: TISSUE
  downstream:
  - target: Congenital heart disease
    causal_link_type: DIRECT
  - target: Bicuspid aortic valve
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  - target: Aortic root aneurysm
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  evidence:
  - reference: PMID:29198724
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "These findings demonstrate the important role of BMP2 in human craniofacial, skeletal, and cardiac development and confirm that individuals heterozygous for BMP2 truncating sequence variants or deletions display a consistent distinct phenotype characterized by short stature and skeletal and cardiac anomalies without neurological deficits."
    explanation: >-
      Establishes cardiac anomalies as part of the core phenotype in the
      defining series.
  - reference: PMID:19116164
    reference_title: "Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Within the heart, BMP2 and BMP4 function coordinately to direct normal lengthening of the outflow tract, proper positioning of the outflow vessels, and septation of the atria, ventricle and atrioventricular canal."
    explanation: >-
      These cardiac results arise from combined Bmp2/Bmp4 mutations. The full text reports no cardiac
      abnormalities in the Bmp2 single heterozygotes examined; compensation in patients was not measured.
    directness: INDIRECT
  - reference: PMID:19116164
    reference_title: Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis.
    supports: REFUTE
    evidence_source: MODEL_ORGANISM
    snippet: whereas no cardiac abnormalities were detected in Bmp2−/+ single mutants
    explanation: >-
      Negative observation in single heterozygotes limits extrapolation of compound-mutant cardiac defects
      to human BMP2 haploinsufficiency.
- name: Eustachian Tube Dysfunction and Middle Ear Effusion
  description: >-
    Recurrent secretory otitis media with secondary conductive hearing impairment was documented in the
    2025 cohort. Craniofacial anatomy is a proposed contributor. This mechanism applies to the documented
    conductive cases; it does not account for every hearing abnormality, including sensorineural loss
    described in a father with a multigene 20p12.3 deletion.
  biological_scale: TISSUE
  downstream:
  - target: Recurrent otitis media
    causal_link_type: DIRECT
  - target: Conductive hearing impairment
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:39970956
      reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "The conductive hearing impairment detected in four individuals (4/5) in our cohort resulted from repeated secretory otitis media."
      explanation: >-
        The word "resulted from" makes this an explicit causal claim about the
        edge, not merely co-occurrence of the two findings.
  - target: Delayed speech and language development
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Hearing loss and facial muscular hypotonia are proposed contributors to articulation difficulties.
      Their causal contributions were not tested, and developmental outcomes vary.
    evidence:
    - reference: PMID:39970956
      reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "We speculate that individuals with BMP2 haploinsufficiency may suffer from articulation difficulties related to facial muscular hypotonia and conductive hearing loss."
      explanation: >-
        The authors advance this as a speculation, and the edge is curated at
        that strength: it is the proposed explanation of the speech delay, not a
        demonstrated one.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Four individuals had recurrent secretory otitis media and needed to go through myringotomy, all of them also had secondary conductive hearing impairment because of secretory otitis media."
    explanation: >-
      Documents the effusion-to-conductive-loss sequence directly, including the
      intervention it required.
phenotypes:
- category: Growth
  name: Short stature
  phenotype_term:
    preferred_term: Short stature
    term:
      id: HP:0004322
      label: Short stature
  description: >-
    Short stature is common but not universal: the 2025 series reported it in six of seven individuals;
    the seventh, Individual 6, was tall. The 2017 table reported height at or below -2 SD in 8/11 assessed
    individuals. These cohort proportions are retained separately. Growth hormone deficiency is not required
    for the growth phenotype.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "All but one individual had short stature (6/7)"
    explanation: >-
      The 2025 cohort count documents short stature in six of seven individuals;
      the tall seventh individual is distinct from these six.
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Height ≤ −2.0 SD ... 8/11 ... 72.7%
    explanation: >-
      The 2017 table reports 8/11 assessed individuals meeting the height threshold.
- category: Craniofacial
  name: Midface retrusion
  frequency: VERY_FREQUENT
  phenotype_term:
    preferred_term: Midface hypoplasia
    term:
      id: HP:0011800
      label: Midface retrusion
  description: >-
    Midface hypoplasia of varying extent, present in every individual of the
    2025 cohort and a core component of the recognisable gestalt.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "All individuals had specific craniofacial features, traits present in all individuals were dental crowding (6/6), midface hypoplasia (7/7) of different extent and long philtrum (7/7)."
    explanation: >-
      Gives the observed frequency (7/7) for midface hypoplasia in the cohort.
- category: Craniofacial
  name: Long philtrum
  frequency: VERY_FREQUENT
  phenotype_term:
    preferred_term: Long philtrum
    term:
      id: HP:0000343
      label: Long philtrum
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "All individuals had specific craniofacial features, traits present in all individuals were dental crowding (6/6), midface hypoplasia (7/7) of different extent and long philtrum (7/7)."
    explanation: >-
      Long philtrum was present in 7 of 7 individuals.
- category: Craniofacial
  name: Dental crowding
  phenotype_term:
    preferred_term: Dental crowding
    term:
      id: HP:0000678
      label: Dental crowding
  description: >-
    Dental crowding was reported in 6/10 assessed individuals in 2017 and all six with dental data in
    the 2025 cohort. The different cohort proportions are reported separately without a syndrome-wide
    frequency band. Reduced jaw size is a plausible contributor, but a primary dental developmental contribution
    is not excluded.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "All individuals had specific craniofacial features, traits present in all individuals were dental crowding (6/6), midface hypoplasia (7/7) of different extent and long philtrum (7/7)."
    explanation: >-
      Dental crowding was present in all 6 individuals with dental data.
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Dental crowding ... 6/10 ... 60.0% ... Anterior open bite ... 5/10 ... 50.0%
    explanation: >-
      The adjacent dental rows in Table 1 report crowding and open bite separately; crowding affected
      6/10 assessed individuals.
- category: Craniofacial
  name: Micrognathia
  phenotype_term:
    preferred_term: Micrognathia
    term:
      id: HP:0000347
      label: Micrognathia
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."
    explanation: >-
      The photographic figure legend enumerating the gestalt in three
      individuals of the cohort, micrognathia among them.
- category: Craniofacial
  name: Cleft palate
  phenotype_term:
    preferred_term: Cleft palate
    term:
      id: HP:0000175
      label: Cleft palate
  description: >-
    Reported in the 20p12.3 deletion series, where it may present as part of a
    Pierre Robin sequence. It is not universal - the 2025 seven-patient cohort
    did not report clefting - so it is curated as occasional rather than core.
  evidence:
  - reference: PMID:21671386
    reference_title: "Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Clinical features were significant for cleft palate and facial dysmorphism in all three patients, including Pierre-Robin sequence in two."
    explanation: >-
      Cleft palate in all three patients of this series, two with BMP2 as the
      only deleted gene.
  - reference: PMID:22965927
    reference_title: "Cleft palate in a multigenerational family with a microdeletion of 20p12.3 involving BMP2."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The father was otherwise healthy with no history of FTT or DD, suggesting high penetrance, yet variable expressivity for haploinsufficiency of BMP2."
    explanation: >-
      An independent multigenerational 20p12.3 deletion family, replicating the
      clefting phenotype and giving the penetrance and expressivity reading
      directly: high penetrance, variable expressivity.
- category: Craniofacial
  name: Pierre-Robin sequence
  phenotype_term:
    preferred_term: Pierre-Robin sequence
    term:
      id: HP:0000201
      label: Pierre-Robin sequence
  evidence:
  - reference: PMID:21671386
    reference_title: "Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Clinical features were significant for cleft palate and facial dysmorphism in all three patients, including Pierre-Robin sequence in two."
    explanation: >-
      Pierre Robin sequence in two of three patients with a BMP2-containing
      20p12.3 deletion.
- category: Craniofacial
  name: Downslanted palpebral fissures
  phenotype_term:
    preferred_term: Downslanted palpebral fissures
    term:
      id: HP:0000494
      label: Downslanted palpebral fissures
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."
    explanation: >-
      Listed among the craniofacial features documented photographically.
- category: Craniofacial
  name: Hypertelorism
  phenotype_term:
    preferred_term: Hypertelorism
    term:
      id: HP:0000316
      label: Hypertelorism
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."
    explanation: >-
      Listed among the craniofacial features documented photographically.
- category: Craniofacial
  name: Broad forehead
  phenotype_term:
    preferred_term: Broad forehead
    term:
      id: HP:0000337
      label: Broad forehead
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."
    explanation: >-
      Listed among the craniofacial features documented photographically.
- category: Craniofacial
  name: Low-set ears
  phenotype_term:
    preferred_term: Low-set, posteriorly rotated ears
    term:
      id: HP:0000369
      label: Low-set ears
  description: >-
    Described together with posterior rotation. Bound to the low-set-ears term
    because the composite HPO term for both is obsolete.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."
    explanation: >-
      Listed among the craniofacial features documented photographically.
- category: Craniofacial
  name: Posteriorly rotated ears
  phenotype_term:
    preferred_term: Posteriorly rotated ears
    term:
      id: HP:0000358
      label: Posteriorly rotated ears
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note craniofacial features; midface hypoplasia, long philtrum, broad forehead, downslanting palpebral fissures, hypertelorism, micro- and retrognathia, low set and posteriorly rotated ears."
    explanation: >-
      Listed among the craniofacial features documented photographically.
- category: Skeletal
  name: Brachydactyly
  phenotype_term:
    preferred_term: Brachydactyly
    term:
      id: HP:0001156
      label: Brachydactyly
  description: >-
    Short digits in hands and feet. The hand finding is best documented in the
    multi-generational 20p12.3 deletion family, where short fifth fingers
    segregate with the deletion through three generations; the foot finding is
    photographic. Distinct in mechanism from brachydactyly type A2, which
    arises from duplication of a BMP2 limb enhancer rather than from loss of
    the gene.
  evidence:
  - reference: PMID:21671386
    reference_title: "Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "deep palmar flexion creases and short 5th fingers"
    explanation: >-
      The proposita of the BMP2-only deletion family. Her mother and maternal
      grandmother, who carry the same deletion, are separately described with
      short fifth fingers, so this is the segregating hand phenotype rather
      than an isolated observation.
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note the dental crowding, sandal gap and the short toes."
    explanation: >-
      The corresponding foot finding, documented photographically in a cohort
      individual.
- category: Skeletal
  name: Short toe
  phenotype_term:
    preferred_term: Short toes
    term:
      id: HP:0001831
      label: Short toe
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note the dental crowding, sandal gap and the short toes."
    explanation: >-
      Short toes documented photographically in a cohort individual.
- category: Skeletal
  name: Sandal gap
  phenotype_term:
    preferred_term: Sandal gap
    term:
      id: HP:0001852
      label: Sandal gap
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Note the dental crowding, sandal gap and the short toes."
    explanation: >-
      Sandal gap documented photographically in a cohort individual.
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Sandal gap (6/6) | + | + | N/A | + | + | + | +
    explanation: >-
      Table 2 reports sandal gap in all six individuals assessed.
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Sandal gap ... 8/11 ... 72.7% ... Toenail dysplasia ... 3/11 ... 27.3%
    explanation: >-
      The 2017 foot findings include sandal gap in 8/11 assessed individuals; the neighboring toenail
      row describes a separate phenotype.
  description: >-
    Sandal gap was reported in 8/11 assessed individuals in 2017 and 6/6 in the 2025 cohort. The differing,
    family-based samples are reported separately without assigning a pooled syndrome-wide frequency.
- category: Skeletal
  name: Scoliosis
  phenotype_term:
    preferred_term: Scoliosis
    term:
      id: HP:0002650
      label: Scoliosis
  description: >-
    Thoracic scoliosis was progressive and required surgery at age 13 in the patient with an intragenic
    BMP2 truncating variant reported in 2021. Scoliosis has also been described in deletion carriers.
  evidence:
  - reference: PMID:33247540
    reference_title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Other skeletal abnormalities included progressive thoracic scoliosis, which required surgical intervention at 13 years of age."
    explanation: >-
      Scoliosis in a patient whose only BMP2 lesion is an intragenic nonsense
      variant, so no neighbouring gene is available to explain it.
- category: Cardiovascular
  name: Bicuspid aortic valve
  phenotype_term:
    preferred_term: Bicuspid aortic valve
    term:
      id: HP:0001647
      label: Bicuspid aortic valve
  description: >-
    Reported once, with aortic root and ascending aortic aneurysm in the same
    patient. It extends the cardiac phenotype beyond septation into
    left-ventricular outflow development, which is a distinct morphogenetic
    field from the atrioventricular cushions the rest of this entry's cardiac
    mechanism runs through.
  evidence:
  - reference: PMID:33247540
    reference_title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We describe a patient harboring a novel de novo BMP2 nonsense variant, who exhibited craniofacial and skeletal features previously described for this trait and the novel findings of bicuspid aortic valve (BAV) and aortic root and ascending aortic aneurysm."
    explanation: >-
      The single reported observation, in a patient with an intragenic nonsense
      variant.
- category: Cardiovascular
  name: Aortic root aneurysm
  phenotype_term:
    preferred_term: Aortic root and ascending aortic aneurysm
    term:
      id: HP:0002616
      label: Aortic root aneurysm
  description: >-
    Reported in the same single patient as the bicuspid aortic valve, and not
    independently replicated. Recorded because aortopathy alongside a bicuspid
    valve carries surveillance implications that a septal defect does not.
  evidence:
  - reference: PMID:33247540
    reference_title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We describe a patient harboring a novel de novo BMP2 nonsense variant, who exhibited craniofacial and skeletal features previously described for this trait and the novel findings of bicuspid aortic valve (BAV) and aortic root and ascending aortic aneurysm."
    explanation: >-
      Names the aneurysm alongside the valve lesion in the same patient.
- category: Cardiovascular
  name: Wolff-Parkinson-White syndrome
  phenotype_term:
    preferred_term: Wolff-Parkinson-White syndrome
    term:
      id: HP:0001716
      label: Wolff-Parkinson-White syndrome
  description: >-
    Ventricular pre-excitation has been reported with BMP2-containing deletions and an intragenic BMP2
    truncating variant. Affected individuals may develop symptomatic palpitations. The molecular mechanism
    of the accessory pathway remains unresolved.
  evidence:
  - reference: PMID:33247540
    reference_title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "an electrocardiogram showed evidence of preexcitation consistent with Wolff–Parkinson–White syndrome (WPW)"
    explanation: >-
      Preexcitation in a patient whose BMP2 lesion is intragenic, which is what
      separates this from the deletion-interval reports.
- category: Neurological
  name: Neural tube defect
  phenotype_term:
    preferred_term: Neural tube defect
    term:
      id: HP:0045005
      label: Neural tube defect
  description: >-
    Reported in the international 18-person cohort. The abstract does not provide a feature-specific denominator;
    no frequency is assigned from that statement.
  evidence:
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies."
    explanation: >-
      The reported spectrum expansion. Cited without a frequency because the
      abstract gives no denominator for these findings.
- category: Neurological
  name: Structural brain anomaly
  phenotype_term:
    preferred_term: Structural brain anomaly
    term:
      id: HP:0012443
      label: Abnormal brain morphology
    coarse_binding_basis: SOURCE_UNSPECIFIED
  description: >-
    Structural brain abnormalities were reported in the 18-person cohort. The abstract does not specify
    their individual forms or denominators.
  evidence:
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies."
    explanation: >-
      The reported spectrum expansion, without a denominator.
- category: Endocrine
  name: Endocrinopathy
  phenotype_term:
    preferred_term: Endocrinopathy
    term:
      id: HP:0000818
      label: Abnormality of the endocrine system
    coarse_binding_basis: SOURCE_UNSPECIFIED
  description: >-
    Endocrine abnormalities were reported in the 18-person cohort. Other reports document growth hormone
    deficiency in multigene deletion carriers; the endocrine spectrum attributable to BMP2 alone remains
    unresolved.
  evidence:
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We also identified patients with neural tube defects, structural brain anomalies, and endocrinopathies."
    explanation: >-
      The reported spectrum expansion, without a denominator.
- category: Skeletal
  name: Prominent sternum
  phenotype_term:
    preferred_term: Prominent sternum
    term:
      id: HP:0000884
      label: Prominent sternum
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "F show Individual 6 at age 44 years, note the prominent sternal bone."
    explanation: >-
      A sternal anomaly documented photographically in an adult cohort
      individual.
- category: Skeletal
  name: Phalangeal osteolysis
  phenotype_term:
    preferred_term: Osteolysis of the phalanges
    term:
      id: HP:0002797
      label: Osteolysis
  description: >-
    Osteolysis of multiple phalanges was identified at age ten in a girl with a de novo truncating BMP2
    variant. The report introduces it as a previously unrecognized feature; the cached abstract does not
    establish its onset or rate of progression.
  evidence:
  - reference: PMID:40285376
    reference_title: "Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "At 10 years old, she presented with short stature and skeletal radiographs revealed osteolysis in multiple phalanges."
    explanation: >-
      Documents osteolysis in one individual; a case report cannot establish its frequency in the disorder.
- category: Cardiovascular
  name: Congenital heart disease
  phenotype_term:
    preferred_term: Congenital heart disease
    term:
      id: HP:0001627
      label: Abnormal heart morphology
  description: >-
    Variable structural heart disease includes septal defects, Ebstein anomaly, transposition of the great
    arteries and pulmonary valve stenosis in the 2017 cohort. Bicuspid aortic valve was reported subsequently.
    Table 1 of the 2017 series records structural malformations in 4/9 assessed individuals; findings
    are not principally restricted to septation.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Haploinsufficiency of BMP2 is associated with short stature, skeletal malformations, hearing impairment, cleft palate and cardiac abnormalities including structural abnormalities and arrhythmias"
    explanation: >-
      Names both structural defects and arrhythmia as part of the cardiac
      spectrum.
  - reference: PMID:40285376
    reference_title: "Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant."
    supports: REFUTE
    evidence_source: HUMAN_CLINICAL
    snippet: "Additional clinical evaluations, including echocardiography and metabolic studies, were unremarkable."
    explanation: >-
      Refutes the claim that cardiac involvement is a constant feature: this
      patient has a confirmed de novo truncating BMP2 variant and entirely
      normal echocardiography. It is the direct evidence for incomplete cardiac
      penetrance.
- category: Auditory
  name: Recurrent otitis media
  phenotype_term:
    preferred_term: Recurrent secretory otitis media
    term:
      id: HP:0000403
      label: Recurrent otitis media
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In our cohort, delayed language development (4/5) and secretory otitis media (4/5) were common."
    explanation: >-
      Gives the observed frequency (4/5) for secretory otitis media.
  description: >-
    Recurrent secretory otitis media was reported in 4/5 assessed individuals in the seven-person 2025
    cohort. A syndrome-wide frequency is not inferred from that family-based sample. Hearing impairment
    in another cohort is not an interchangeable denominator for otitis media.
- category: Auditory
  name: Conductive hearing impairment
  phenotype_term:
    preferred_term: Conductive hearing impairment
    term:
      id: HP:0000405
      label: Conductive hearing impairment
  description: >-
    Conductive hearing loss associated with recurrent secretory otitis media was reported in four individuals
    in the 2025 cohort. The narrative gives 4/5, whereas Table 3 records four affected, two unaffected
    and one unassessed individual. This denominator discrepancy prevents treating the narrative proportion
    as a precise penetrance estimate.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The conductive hearing impairment detected in four individuals (4/5) in our cohort resulted from repeated secretory otitis media."
    explanation: >-
      States both the frequency and that the loss is conductive and derived
      from the effusion.
- category: Neurodevelopmental
  name: Delayed speech and language development
  phenotype_term:
    preferred_term: Delayed speech and language development
    term:
      id: HP:0000750
      label: Delayed speech and language development
  description: >-
    Delayed language development was reported in 4/5 assessed individuals in the 2025 cohort. Speech and
    articulation delay can occur with otherwise normal cognition, but some individuals have motor delay
    or learning difficulties. The 2017 table does not provide a speech-delay denominator, and its cognitive
    findings cannot substitute for language assessment. No syndrome-wide frequency is assigned.
    Hearing impairment and facial hypotonia are proposed contributors to articulation difficulties;
    the contribution of BMP2 alone to global developmental delay remains unresolved.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The most reported developmental delay in our cohort was delayed speech (4/5), including articulation."
    explanation: >-
      Gives the frequency and specifies that the delay is in the speech domain.
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Altogether these results indicate that the delayed speech development is not associated with low intelligence or general developmental delay."
    explanation: >-
      Supports curating this as an isolated speech phenotype rather than as a
      marker of global delay.
- category: Neurological
  name: Hypotonia in infancy
  frequency: OCCASIONAL
  phenotype_term:
    preferred_term: Hypotonia in infancy
    term:
      id: HP:0008947
      label: Floppy infant
  description: >-
    Hypotonia in infancy was observed in three individuals in the 2017 cohort and in subsequent cases.
    The observations concern infancy and are not restricted to the neonatal period.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "whereas two of them also had hypotonia in infancy (Individuals 4 and 7)"
    explanation: >-
      Two of seven cohort individuals had infantile hypotonia.
- category: Skeletal
  name: Clinodactyly of the 5th finger
  frequency: FREQUENT
  phenotype_term:
    preferred_term: Fifth finger clinodactyly
    term:
      id: HP:0004209
      label: Clinodactyly of the 5th finger
  description: >-
    Fifth-finger clinodactyly occurred in 4/11 assessed individuals in Table 1 of the 2017 series. It
    can coexist with shortening of the fifth proximal phalanx.
  evidence:
  - reference: PMID:33247540
    reference_title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Distinctive facial features included broad forehead, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate along with commonly associated skeletal anomalies of short stature, fifth finger clinodactyly, and wide sandal gap."
    explanation: >-
      Lists fifth finger clinodactyly among the commonly associated skeletal
      anomalies of the BMP2 phenotype.
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Phalangeal abnormalities ... 10/10 ... 100.0% ... Fifth-finger clinodactyly ... 4/11 ... 36.4%
    explanation: >-
      Table 1 reports fifth-finger clinodactyly in 4/11 assessed individuals, supporting the FREQUENT
      band.
- category: Craniofacial
  name: Thin upper lip vermilion
  phenotype_term:
    preferred_term: Thin upper lip
    term:
      id: HP:0000219
      label: Thin upper lip vermilion
  description: >-
    Part of the facial gestalt, listed with the broad forehead, long philtrum
    and dental crowding already curated here.
  evidence:
  - reference: PMID:33247540
    reference_title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Distinctive facial features included broad forehead, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate along with commonly associated skeletal anomalies of short stature, fifth finger clinodactyly, and wide sandal gap."
    explanation: >-
      Names a thin upper lip among the distinctive facial features of the BMP2
      phenotype.
- category: Integumentary
  name: Toenail dysplasia
  phenotype_term:
    preferred_term: Toenail dysplasia
    term:
      id: HP:0100797
      label: Toenail dysplasia
  description: >-
    Toenail dysplasia was reported in 3/11 assessed individuals in the 2017 cohort and 5/6 in Table 3
    of the 2025 cohort. These small, family-based cohorts give materially different proportions. No syndrome-wide
    frequency band or pooled penetrance estimate is assigned.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "G shows toenail dysplasia in Individual 5 at seven years of age."
    explanation: >-
      A single documented observation in the cohort.
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Toenail dysplasia | Yes | No | N/A | Yes | Yes | Yes | Yes
    explanation: >-
      Table 3 lists five affected individuals, one unaffected individual and one with unavailable data:
      5/6 assessed.
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Sandal gap ... 8/11 ... 72.7% ... Toenail dysplasia ... 3/11 ... 27.3%
    explanation: >-
      Table 1 distinguishes sandal gap (8/11) from toenail dysplasia (3/11); the latter contrasts with
      5/6 in the 2025 cohort.
- name: 11 pairs of ribs
  category: Skeletal
  phenotype_term:
    preferred_term: 11 pairs of ribs
    term:
      id: HP:0000878
      label: 11 pairs of ribs
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Skeletal anomalies include proportionate short stature, short fifth proximal phalanges, 11 pairs of ribs, and a wide sandal gap
    explanation: The 2017 human clinical results explicitly report reduced rib number; this is not inferred solely from mice.
- name: Obstructive sleep apnea
  category: Respiratory
  phenotype_term:
    preferred_term: Obstructive sleep apnea
    term:
      id: HP:0002870
      label: Obstructive sleep apnea
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Four individuals (F2-1, F2-2, S1, and S3) had obstructive sleep apnea diagnosed in childhood or adulthood.
    explanation: Documents clinically diagnosed obstructive sleep apnea across childhood and adult ages.
- name: Delayed skeletal maturation
  category: Skeletal
  phenotype_term:
    preferred_term: Delayed skeletal maturation
    term:
      id: HP:0002750
      label: Delayed skeletal maturation
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Less common features noted in at least two individuals were conductive hearing impairment, low-set posteriorly rotated ears, synophrys, sternal deformity, delayed bone age in early childhood, and L5/S1 spondylolisthesis.
    explanation: The human cohort records delayed bone age in early childhood.
- name: L5-S1 spondylolisthesis
  category: Skeletal
  phenotype_term:
    preferred_term: L5-S1 spondylolisthesis
    term:
      id: HP:0008489
      label: Spondylolisthesis at L5-S1
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Less common features noted in at least two individuals were conductive hearing impairment, low-set posteriorly rotated ears, synophrys, sternal deformity, delayed bone age in early childhood, and L5/S1 spondylolisthesis.
    explanation: The human cohort identifies the specific lumbosacral level of vertebral slippage.
- name: Synophrys
  category: Craniofacial
  phenotype_term:
    preferred_term: Synophrys
    term:
      id: HP:0000664
      label: Synophrys
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Less common features noted in at least two individuals were conductive hearing impairment, low-set posteriorly rotated ears, synophrys, sternal deformity, delayed bone age in early childhood, and L5/S1 spondylolisthesis.
    explanation: Synophrys is explicitly reported in the human cohort.
- name: Anteverted nares
  category: Craniofacial
  phenotype_term:
    preferred_term: Anteverted nares
    term:
      id: HP:0000463
      label: Anteverted nares
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Affected individuals share similar distinctive craniofacial features such as a broad forehead with temporal narrowing, a flat midface, anteverted nares, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate
    explanation: The 2017 cohort describes anteverted nares in the facial phenotype.
- name: High palate
  category: Craniofacial
  phenotype_term:
    preferred_term: High palate
    term:
      id: HP:0000218
      label: High palate
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Affected individuals share similar distinctive craniofacial features such as a broad forehead with temporal narrowing, a flat midface, anteverted nares, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate
    explanation: High-arched palate is included separately from cleft palate; neither finding is implied to occur in every individual.
- name: Short nose
  category: Craniofacial
  description: >-
    Short nose was reported in 12/12 individuals in the clinically ascertained 2017 cohort.
  phenotype_term:
    preferred_term: Short nose
    term:
      id: HP:0003196
      label: Short nose
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Short nose ... 12/12 ... 100.0% ... Anteverted nares ... 12/12 ... 100.0%
    explanation: >-
      Adjacent Table 1 rows describe the nasal phenotype: short nose and anteverted nares each occurred
      in all twelve individuals. This is a clinically ascertained cohort, not a population penetrance
      estimate.
- name: Narrow forehead
  category: Craniofacial
  description: >-
    Bitemporal narrowing was reported in 8/10 assessed individuals in the 2017 cohort, sometimes alongside
    a broad-appearing forehead.
  phenotype_term:
    preferred_term: Narrow forehead
    term:
      id: HP:0000341
      label: Narrow forehead
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Affected individuals share similar distinctive craniofacial features such as a broad forehead with temporal narrowing, a flat midface, anteverted nares, a long philtrum, a thin upper lip, crowded dentition, and a cleft or high-arched palate
    explanation: >-
      The clinical description reports temporal narrowing alongside a broad forehead. Table 1 separately
      records temporal narrowing in 8/10 assessed individuals.
- name: Anterior open-bite malocclusion
  category: Craniofacial
  description: >-
    Anterior open bite was reported in 5/10 assessed individuals in the 2017 cohort.
  phenotype_term:
    preferred_term: Anterior open-bite malocclusion
    term:
      id: HP:0009102
      label: Anterior open-bite malocclusion
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Anterior open bite ... 5/10 ... 50.0%
    explanation: >-
      Table 1 reports the feature and its assessed denominator. This is a small selected cohort, not a
      population penetrance estimate.
- name: Epicanthus
  category: Craniofacial
  description: >-
    Epicanthal folds were recorded in 3/7 individuals in Table 2 of the 2025 cohort.
  phenotype_term:
    preferred_term: Epicanthus
    term:
      id: HP:0000286
      label: Epicanthus
  evidence:
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Epicanthal folds (3/7) | + | − | − | + | + | − | −
    explanation: >-
      The table reports this feature across the seven individuals. Relatedness and ascertainment limit
      generalization of the cohort proportion.
- name: Everted lower lip vermilion
  category: Craniofacial
  description: >-
    Eversion of the lower lip vermilion was recorded in 5/7 individuals in Table 2 of the 2025 cohort.
  phenotype_term:
    preferred_term: Everted lower lip vermilion
    term:
      id: HP:0000232
      label: Everted lower lip vermilion
  evidence:
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Everted lower lip vermilion (5/7) | + | − | + | + | + | − | +
    explanation: >-
      The table reports this feature across the seven individuals. Relatedness and ascertainment limit
      generalization of the cohort proportion.
- name: Narrow mouth
  category: Craniofacial
  description: >-
    Microstomia was reported in Individual 4 of the 2025 cohort. No syndrome-wide frequency is assigned
    from this single observation.
  phenotype_term:
    preferred_term: Narrow mouth
    term:
      id: HP:0000160
      label: Narrow mouth
  evidence:
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Microstomia (1/7) | − | − | − | + | − | − | −
    explanation: >-
      Table 2 identifies the affected individual.
- name: Abnormal scapula morphology
  category: Skeletal
  description: >-
    Scapular abnormalities were reported in the 2025 cohort. Table 2 gives 3/5 in its row label but four
    positive cells among six assessed individuals; a precise frequency is therefore not assigned. The
    table does not specify the scapular lesions.
  phenotype_term:
    preferred_term: Abnormal scapula morphology
    term:
      id: HP:0000782
      label: Abnormal scapula morphology
    coarse_binding_basis: SOURCE_UNSPECIFIED
  evidence:
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Scapula abnormality (3/5) | + | + | N/A | + | + | − | −
    explanation: >-
      The feature is present, but summary and individual-cell counts disagree.
- name: Abnormality of the vertebral column
  category: Skeletal
  description: >-
    Spinal anomalies were reported in three of four assessed individuals in the 2025 table. The aggregate
    table does not specify individual lesions; scoliosis and L5-S1 spondylolisthesis from other reports
    are curated separately.
  phenotype_term:
    preferred_term: Abnormality of the vertebral column
    term:
      id: HP:0000925
      label: Abnormality of the vertebral column
    coarse_binding_basis: SOURCE_UNSPECIFIED
  evidence:
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Spinal anomalies (3/4) | + | N/A | N/A | N/A | + | + | −
    explanation: >-
      Table 2 reports spinal skeletal anomalies without detailing their morphology.
- name: Pectus excavatum
  category: Skeletal
  description: >-
    Pectus excavatum was documented in the patient with an intragenic BMP2 truncating variant reported
    in 2021.
  phenotype_term:
    preferred_term: Pectus excavatum
    term:
      id: HP:0000767
      label: Pectus excavatum
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: the patient’s physical exam was notable for prominent pectus excavatum, joint laxity, velvety soft skin without atrophic scars or transparency
    explanation: >-
      The physical examination describes a depressed sternum separately from other reported sternal abnormalities.
- name: Joint hypermobility
  category: Skeletal
  description: >-
    Joint laxity was documented in the 2021 intragenic-variant case; distribution and quantitative range-of-motion
    measurements were not reported.
  phenotype_term:
    preferred_term: Joint hypermobility
    term:
      id: HP:0001382
      label: Joint hypermobility
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: the patient’s physical exam was notable for prominent pectus excavatum, joint laxity, velvety soft skin without atrophic scars or transparency
    explanation: >-
      The report documents joint laxity without establishing generalized hypermobility.
- name: Ebstein anomaly
  category: Cardiovascular
  description: >-
    Reported among the structural cardiac lesions in the 2017 defining cohort. The total cardiac-malformation
    denominator does not establish the frequency of this individual lesion.
  phenotype_term:
    preferred_term: Ebstein anomaly of the tricuspid valve
    term:
      id: HP:0010316
      label: Ebstein anomaly of the tricuspid valve
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis.
    explanation: >-
      The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.
- name: Transposition of the great arteries
  category: Cardiovascular
  description: >-
    Reported among the structural cardiac lesions in the 2017 defining cohort. The total cardiac-malformation
    denominator does not establish the frequency of this individual lesion.
  phenotype_term:
    preferred_term: Transposition of the great arteries
    term:
      id: HP:0001669
      label: Transposition of the great arteries
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis.
    explanation: >-
      The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.
- name: Ventricular septal defect
  category: Cardiovascular
  description: >-
    Reported among the structural cardiac lesions in the 2017 defining cohort. The total cardiac-malformation
    denominator does not establish the frequency of this individual lesion.
  phenotype_term:
    preferred_term: Ventricular septal defect
    term:
      id: HP:0001629
      label: Ventricular septal defect
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis.
    explanation: >-
      The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.
- name: Valvular pulmonary stenosis
  category: Cardiovascular
  description: >-
    Reported among the structural cardiac lesions in the 2017 defining cohort. The total cardiac-malformation
    denominator does not establish the frequency of this individual lesion.
  phenotype_term:
    preferred_term: Valvular pulmonary stenosis
    term:
      id: HP:0034350
      label: Valvular pulmonary stenosis
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Cardiac malformations were reported in 4/9 (44.4%) individuals and included Ebstein anomaly, transposition of the great arteries, ventricular septal defects, and pulmonary valve stenosis.
    explanation: >-
      The cohort explicitly names this cardiac lesion; 4/9 refers to any structural cardiac malformation.
diagnosis:
- name: Chromosomal microarray
  description: >-
    Detects deletions encompassing BMP2 and defines their genomic extent. Gene content informs interpretation
    of additional findings, but deletion size alone does not predict their penetrance.
  presence: PRESENT
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "For larger deletions, validation and segregation were done using array comparative genomic hybridisation"
    explanation: >-
      Array CGH is the method used to confirm and size the deletions in this
      cohort.
- name: Exome or genome sequencing
  description: >-
    Can identify intragenic BMP2 variants, including truncating, frameshift, splice-altering and selected
    missense variants. Coverage and variant interpretation matter; low-level parental mosaicism may require
    targeted assays or another tissue.
  presence: PRESENT
  evidence:
  - reference: PMID:40285376
    reference_title: "Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Whole-exome sequencing identified a de novo heterozygous truncating variant (c.440C>G; p.Ser147*) in BMP2."
    explanation: >-
      Documents sequence-level identification of a de novo truncating BMP2 variant; the abstract does
      not establish a prior negative microarray.
- name: Growth hormone axis evaluation
  description: >-
    Recommended in the workup of short stature here, because partial isolated
    growth hormone deficiency has been documented in one individual and
    responded to replacement. Whether it is part of the syndrome or coincidental
    is unresolved.
  presence: VARIABLE
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Until then, we suggest that evaluation of growth hormone levels should be included in the medical investigation."
    explanation: >-
      The recommendation, stated with the uncertainty that motivates it.
- name: Audiological surveillance and middle ear examination
  description: >-
    Regular assessment of hearing and of the middle ear, proposed as routine
    surveillance because effusion and conductive loss are common and treatable.
  presence: PRESENT
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Based on our observations, we recommend that evaluation of language development and regular controls of the middle ear are included in the surveillance of these individuals."
    explanation: >-
      The seven-person 2025 cohort explicitly recommends surveillance of middle-ear disease and language
      development.
- name: Longitudinal skeletal radiography
  description: >-
    Longitudinal skeletal monitoring was proposed by the authors of the phalangeal osteolysis case report.
    The published abstract reports detection at age ten but does not provide earlier radiographic comparisons
    or a validated surveillance interval.
  presence: VARIABLE
  evidence:
  - reference: PMID:40285376
    reference_title: "Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "These findings highlight the necessity of longitudinal skeletal monitoring in BMP2-related conditions"
    explanation: >-
      The recommendation as stated by the reporting authors.
- name: Cardiac imaging and rhythm assessment
  description: >-
    Echocardiography and electrocardiography characterize structural and rhythm involvement. A patient
    with bicuspid aortic valve and WPW underwent annual echocardiography that documented progressive aortic
    dilatation. This is a case-based surveillance example, not a validated universal interval.
  presence: VARIABLE
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: The patient was monitored annually with echocardiograms for progression of the cardiovascular involvement. Slow progressive dilation of aortic root and ascending aorta was noted without aortic stenosis and, at most, mild aortic insufficiency
    explanation: >-
      Documents longitudinal imaging and its findings in the intragenic-variant case.
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: an electrocardiogram showed evidence of preexcitation consistent with Wolff–Parkinson–White syndrome (WPW).
    explanation: >-
      ECG identified pre-excitation in the patient evaluated for palpitations.
treatments:
- name: Myringotomy and Ventilation Tube Insertion
  description: >-
    Drainage of persistent middle ear effusion. In the 2025 cohort all four
    individuals with recurrent secretory otitis media required myringotomy, and
    all four had conductive hearing loss secondary to the effusion, so this
    addresses the reversible component of the hearing phenotype.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: myringotomy with ear tube placement
    term:
      id: NCIT:C70906
      label: Myringotomy with Ear Tube Placement
  target_mechanisms:
  - target: Eustachian Tube Dysfunction and Middle Ear Effusion
    description: >-
      Drains the effusion that is the proximate cause of the conductive loss.
    evidence:
    - reference: PMID:39970956
      reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "The conductive hearing impairment detected in four individuals (4/5) in our cohort resulted from repeated secretory otitis media."
      explanation: >-
        Identifies the effusion as the cause of the hearing loss, which is what
        makes draining it the mechanistically targeted intervention.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Four individuals had recurrent secretory otitis media and needed to go through myringotomy, all of them also had secondary conductive hearing impairment because of secretory otitis media."
    explanation: >-
      Documents the intervention and the indication in this cohort.
- name: Adenoidectomy
  description: >-
    Adenoid hypertrophy was treated surgically in three individuals with recurrent secretory otitis media
    in the 2025 cohort. Its precise causal contribution to their effusions was not tested.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: adenoidectomy
    term:
      id: NCIT:C51697
      label: Adenoidectomy
  target_mechanisms:
  - target: Eustachian Tube Dysfunction and Middle Ear Effusion
    evidence:
    - reference: PMID:39970956
      reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Three of them also had adenoid hypertrophy and underwent adenoidectomy."
      explanation: >-
        Adenoid hypertrophy co-occurred with the effusions in three of the four
        affected individuals, which is the basis for treating it as part of the
        same obstructive mechanism. Co-occurrence rather than a demonstrated
        causal contribution.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Three of them also had adenoid hypertrophy and underwent adenoidectomy."
    explanation: >-
      Documents the intervention in three of the four affected individuals.
- name: Growth Hormone Replacement
  description: >-
    Growth hormone treatment was associated with improved growth in Individual 5 of the 2025 cohort, who
    had partial isolated growth hormone deficiency and a multigene deletion. Table 3 also records treatment
    for short stature in Individual 7 despite normal GH testing. These observations do not establish efficacy
    for the syndrome as a whole.
  therapeutic_modality: PROTEIN_REPLACEMENT
  treatment_term:
    preferred_term: growth hormone therapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: recombinant human growth hormone
      term:
        id: NCIT:C837
        label: Somatropin
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Individual 5 had partial, isolated, growth hormone deficiency"
    explanation: >-
      Identifies partial growth hormone deficiency in Individual 5. Table 3 also records GH treatment
      of Individual 7 despite normal GH testing.
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Individual 5, who presented with partial growth hormone deficiency, responded well to growth hormone treatment."
    explanation: >-
      The reported outcome. A single treated individual, so this is a case
      observation rather than evidence of efficacy in the syndrome.
- name: Speech and Language Therapy
  description: >-
    Supports speech, articulation and language development. Hearing and developmental assessment can identify
    additional needs; normal intelligence should not be assumed solely from the BMP2 diagnosis.
  therapeutic_modality: BEHAVIORAL
  treatment_term:
    preferred_term: speech and language therapy
    term:
      id: NCIT:C159273
      label: Speech Language Therapy
  target_phenotypes:
  - preferred_term: Delayed speech and language development
    term:
      id: HP:0000750
      label: Delayed speech and language development
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Delayed speech, secretory otitis media and conductive hearing loss are common features that require medical attention."
    explanation: >-
      Establishes speech delay as a management target. Cited for the indication;
      no trial of speech therapy in this disorder has been reported.
- name: Cardiac Radiofrequency Ablation
  description: >-
    Successful radiofrequency ablation was reported at age 13 for a left-sided accessory pathway in a
    patient with WPW and an intragenic BMP2 truncating variant. This treats the documented arrhythmia
    substrate.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: cardiac radiofrequency ablation
    term:
      id: NCIT:C170884
      label: Cardiac Radiofrequency Ablation
  target_phenotypes:
  - preferred_term: Wolff-Parkinson-White syndrome
    term:
      id: HP:0001716
      label: Wolff-Parkinson-White syndrome
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: His accessory pathway, which was left sided, was found to have a shortest conducted R–R interval of greater than 250 ms. Radiofrequency ablation was successful.
    explanation: >-
      Documents the accessory pathway and successful ablation in a single patient.
- name: Physical and Occupational Therapy
  description: >-
    Hypotonia gradually improved during the early years of life with physical and occupational therapy
    in the 2021 reported patient. The uncontrolled observation does not separate treatment effect from
    developmental change.
  therapeutic_modality: BEHAVIORAL
  treatment_term:
    preferred_term: physical therapy
    term:
      id: NCIT:C15302
      label: Physical Therapy
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: The hypotonia gradually improved over the first few years of life with occupational and physical therapy.
    explanation: >-
      Reports supportive therapy and the clinical course in one patient.
- name: Mandibular Distraction Osteogenesis
  description: >-
    Two individuals with Pierre Robin sequence in the 2017 cohort required mandibular distraction osteogenesis.
    This is reported clinical management of severe mandibular underdevelopment; the cohort does not quantify
    comparative efficacy.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: mandibular distraction osteogenesis
    term:
      id: NCIT:C16186
      label: Orthopedic Surgical Procedure
  target_phenotypes:
  - preferred_term: Micrognathia
    term:
      id: HP:0000347
      label: Micrognathia
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: had Pierre Robin sequence and a cleft palate, and two of them required mandibular distraction osteogenesis.
    explanation: >-
      Reports the procedure in two of the three individuals with Pierre Robin sequence.
- name: Surgery for Progressive Scoliosis
  description: >-
    Surgical intervention at age thirteen was reported for progressive thoracic scoliosis in the 2021
    patient. The report does not specify the operative technique or a syndrome-specific threshold.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: surgical correction of scoliosis
    term:
      id: NCIT:C16186
      label: Orthopedic Surgical Procedure
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Other skeletal abnormalities included progressive thoracic scoliosis, which required surgical intervention at 13 years of age.
    explanation: >-
      Documents orthopedic surgical management in the intragenic-variant case.
animal_models:
- name: Heterozygous Bmp2 knockout mouse
  species: Mouse
  genotype: Bmp2 heterozygous null
  publication: PMID:29198724
  description: >-
    A heterozygous Bmp2-null model supports dosage sensitivity through growth and rib abnormalities. The
    2017 study measured the skeleton directly; additional axial and survival findings in the 2009 study
    depend on its genetic background.
  modeled_mechanisms:
  - target: BMP2 Haploinsufficiency
    relationship: RECAPITULATES
    fidelity: HIGH
    model_scale: ORGANISM
    description: >-
      Loss of one Bmp2 allele reproduces reduced body length and rib abnormalities. Patient ligand concentrations
      were not measured.
    limitations: >-
      The report describes phenotypic similarity for growth and skeletal
      features; it does not claim the craniofacial gestalt or the cardiac
      anomalies are reproduced, so the model is not established as covering
      those arms.
    readouts:
    - name: Axial skeletal defects in Bmp2 heterozygous adults
      target: BMP2 Haploinsufficiency
      direction: INCREASED
      interpretation: >-
        The 2009 study found defects in dorsal fusion of cervical vertebrae in 3/9 and defects of the
        13th rib in 7/9 Bmp2 heterozygotes. The cervical finding is failure of dorsal fusion, not excessive
        fusion between vertebrae. These are cohort-specific mouse observations.
      evidence:
      - reference: PMID:19116164
        reference_title: "Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis."
        supports: SUPPORT
        evidence_source: MODEL_ORGANISM
        snippet: "Notably, we detected identical defects in dorsal fusion of one or more cervical vertebrae (Fig. 1A and B) as well as defects in formation of the 13th rib (Fig. 1C and D) in 33% and 77%, respectively, of all Bmp2−/+ skeletons analyzed (n = 9)."
        explanation: >-
          The measurement itself, in Bmp2 heterozygotes rather than the
          Bmp4 animals named earlier in the same passage as prior art.
    - name: Reduced body length with preserved femur and tibia lengths
      target: BMP2 Haploinsufficiency
      direction: DECREASED
      interpretation: >-
        The 2017 heterozygote comparison found reduced total body length without shorter femora or tibiae.
        It supports the growth phenotype without demonstrating generalized long-bone growth-plate failure.
      evidence:
      - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
        reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
        supports: SUPPORT
        evidence_source: MODEL_ORGANISM
        snippet: We observed that the body of heterozygous ... mice was significantly shorter than that of wild-type mice, consistent with short stature in human individuals, but the two groups of mice showed no differences in femur or tibia length
        explanation: >-
          Direct morphometry distinguishes total body length from long-bone length.
    - name: Preserved femoral mechanical properties
      target: BMP2 Haploinsufficiency
      direction: UNCHANGED
      interpretation: >-
        Despite reduced bone mineral content and volume, three-point bending did not detect impaired femoral
        mechanics in the 2017 heterozygotes. This limits inference of universal fragility from complete
        conditional-null mice.
      evidence:
      - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
        reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
        supports: SUPPORT
        evidence_source: MODEL_ORGANISM
        snippet: We did not observe any significant differences in maximum load, yield load, work to failure, or stiffness between the two groups
        explanation: >-
          Negative mechanical testing result in Bmp2 heterozygotes compared with wild-type littermates.
    evidence:
    - reference: PMID:29198724
      reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Additionally, we observed similarity to the human phenotype of short stature and skeletal anomalies in a heterozygous Bmp2-knockout mouse model, suggesting that haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions encompassing BMP2."
      explanation: >-
        Attests that this model is informative for the haploinsufficiency node,
        by the authors' own comparison with the human phenotype.
  evidence:
  - reference: PMID:29198724
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Additionally, we observed similarity to the human phenotype of short stature and skeletal anomalies in a heterozygous Bmp2-knockout mouse model, suggesting that haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions encompassing BMP2."
    explanation: >-
      The comparison that makes this the reference model for the disorder.
- name: Wnt1-Cre;Bmp2 flox/flox cranial neural crest conditional knockout mouse
  species: Mouse
  genotype: Wnt1-Cre;Bmp2 fl/fl
  publication: PMID:30413887
  description: >-
    Tissue-specific homozygous deletion of Bmp2 in cranial neural crest,
    generated explicitly to model the human Pierre Robin sequence caused by BMP2
    haploinsufficiency.
  modeled_mechanisms:
  - target: Impaired Cranial Neural Crest Osteogenic Differentiation
    relationship: RECAPITULATES
    fidelity: MODERATE
    model_scale: CELLULAR
    description: >-
      Reduced proliferation and osteogenic differentiation of mandibular
      progenitors is measured directly in this model.
    limitations: >-
      Homozygous conditional loss in one lineage, not a heterozygous
      whole-organism halving, so it demonstrates the requirement rather than
      the sufficiency of a halved dose. The mutants die at birth, which is far
      more severe than the human disorder.
    evidence:
    - reference: PMID:30413887
      reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Further studies revealed obvious reduction in cell proliferation and differentiation of osteogenic progenitors in the mandible of the mutants, attributing to the micrognathia phenotype."
      explanation: >-
        The measured progenitor defect is what makes this model informative for
        the cranial-neural-crest osteogenic node.
  - target: Craniofacial Skeletal Hypoplasia
    relationship: PARTIALLY_RECAPITULATES
    fidelity: MODERATE
    model_scale: TISSUE
    description: >-
      Micrognathia, cleft palate, zygomatic and mandibular hypoplasia are all
      reproduced.
    limitations: >-
      Complete, lineage-restricted loss produces neonatal lethality and fully penetrant cleft palate.
      Species and genotype differences prevent a quantitative prediction of human heterozygous severity.
    evidence:
    - reference: PMID:30413887
      reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Lateral views of 3D reconstructions from microCT scans further confirmed severe craniofacial bone defects in mutant mice"
      explanation: >-
        Imaging confirmation of the craniofacial skeletal hypoplasia this link
        is cited for, rather than gross inspection alone.
  evidence:
  - reference: PMID:30413887
    reference_title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Mutant mice exhibit severe PRS with a significantly reduced size of craniofacial bones, cleft palate, malformed tongue and micrognathia."
    explanation: >-
      The phenotype that makes this model informative for the craniofacial arm.
- name: AV myocardial Bmp2 conditional knockout mouse
  species: Mouse
  genotype: Bmp2 conditional null in atrioventricular myocardium
  publication: PMID:16314491
  description: >-
    Inactivation of Bmp2 in the atrioventricular myocardium, which is the source
    of the signal that induces endocardial transformation.
  modeled_mechanisms:
  - target: Failed Endocardial Cushion Mesenchymal Transition
    relationship: RECAPITULATES
    fidelity: MODERATE
    model_scale: TISSUE
    description: >-
      Loss of cushion EMT, of cardiac jelly, and of AV myocardial patterning.
    limitations: >-
      Complete tissue-restricted loss rather than a halved organism-wide dose,
      so it identifies the required signal without establishing that
      heterozygosity alone produces the human septal defects. It also
      reproduces no other arm of the syndrome.
    evidence:
    - reference: PMID:16314491
      reference_title: "Bmp2 is essential for cardiac cushion epithelial-mesenchymal transition and myocardial patterning."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Bmp2 is required for myocardial expression of Has2, a crucial component of the cardiac jelly matrix."
      explanation: >-
        A specific molecular readout measured in this model, grounding the
        cushion-formation claim in more than gross morphology.
  evidence:
  - reference: PMID:16314491
    reference_title: "Bmp2 is essential for cardiac cushion epithelial-mesenchymal transition and myocardial patterning."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Here, we inactivated bone morphogenetic protein 2 (Bmp2) in the AV myocardium of mice. We show that Bmp2 has three functions in the AV canal: to enhance formation of the cardiac jelly, to induce endocardial EMT and to pattern the AV myocardium."
    explanation: >-
      The model and its three measured cardiac phenotypes.
- name: Limb-conditional Bmp2 knockout mouse
  species: Mouse
  genotype: Bmp2 conditional null restricted to the limb skeleton
  publication: PMID:17099713
  description: >-
    Limb-restricted Bmp2 deletion permits early bone formation but produces spontaneous non-healing fractures.
    The observed postnatal phenotype does not imply that deletion was induced only after the skeleton
    formed.
  modeled_mechanisms:
  - target: Deficient Skeletal Repair and Bone Homeostasis
    relationship: RECAPITULATES
    fidelity: LOW
    model_scale: TISSUE
    description: >-
      Spontaneous non-healing fractures establish BMP2 as required to initiate
      bone repair.
    limitations: >-
      Homozygous limb-restricted loss, and the human phenotype it is invoked
      for - phalangeal osteolysis - has been reported in a single patient. The
      model shows that a repair requirement exists, not that a halved human dose
      breaches it.
    evidence:
    - reference: PMID:17099713
      reference_title: "BMP2 activity, although dispensable for bone formation, is required for the initiation of fracture healing."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Mice lacking the ability to produce BMP2 in their limb bones have spontaneous fractures that do not resolve with time."
      explanation: >-
        The observed skeletal-maintenance failure this link is cited for.
  evidence:
  - reference: PMID:17099713
    reference_title: "BMP2 activity, although dispensable for bone formation, is required for the initiation of fracture healing."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Here we demonstrate that BMP2 is a necessary component of the signaling cascade that governs fracture repair."
    explanation: >-
      The finding this model contributes, distinct from the developmental
      phenotypes of the other models here.
- name: Zebrafish bmp2b ventralization assay for patient missense alleles
  species: Zebrafish
  genotype: patient-derived BMP2 missense alleles assayed against bmp2b function
  publication: PMID:37125634
  description: >-
    Not a disease model but a variant-function assay: each patient missense
    allele is tested for its ability to support bmp2b-driven embryonic
    dorsoventral patterning. Its purpose is allele interpretation, which is why
    it is linked to the haploinsufficiency node rather than to any phenotype.
  modeled_mechanisms:
  - target: BMP2 Haploinsufficiency
    relationship: MEASURES
    fidelity: MODERATE
    model_scale: ORGANISM
    description: >-
      Reads out whether a given missense allele retains BMP2 function, and so
      whether it belongs in the same loss-of-function class as the truncating
      alleles.
    limitations: >-
      The readout is embryonic ventralization in a fish, which is not a
      craniofacial, skeletal or cardiac phenotype and shares no tissue context
      with the human disease. It measures whether the protein works at all, not
      how a halved dose behaves in the affected human tissues.
    evidence:
    - reference: PMID:37125634
      reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Missense variants modeled in zebrafish resulted in loss of protein function."
      explanation: >-
        The assay result that places patient missense alleles in the
        loss-of-function class.
  evidence:
  - reference: PMID:37125634
    reference_title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Patient-derived missense variants were modeled in zebrafish to examine their effect on the ability of bmp2b to promote embryonic ventralization."
    explanation: >-
      States what the assay is and what it reads out.
differential_diagnoses:
- name: SCUBE3-Related Short Stature Syndrome
  disease_term:
    preferred_term: short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 2
    term:
      id: MONDO:0030953
      label: short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 2
  description: >-
    SSFSC2, the type-2 entity whose MONDO label differs from this one only in a
    trailing digit. It is autosomal recessive, caused by biallelic SCUBE3
    variants, and prominently features dental anomalies. SCUBE3 is itself a
    BMP2/BMP4 co-receptor, so the two disorders converge on reduced BMP
    signalling from opposite ends of the same axis, which is why the clinical
    overlap is real rather than nominal.
  distinguishing_features:
  - Autosomal recessive rather than autosomal dominant inheritance
  - OMIM 619184 rather than OMIM 617877
  - SCUBE3 on 6p21.31 rather than BMP2 on 20p12.3
  - Dental abnormalities are prominent in the original SCUBE3 cohort.
  evidence:
  - reference: PMID:33308444
    reference_title: "SCUBE3 loss-of-function causes a recognizable recessive developmental disorder due to defective bone morphogenetic protein signaling."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Eighteen affected individuals from nine unrelated families showed a consistent phenotype characterized by reduced growth, skeletal features, distinctive craniofacial appearance, and dental anomalies."
    explanation: >-
      The SSFSC2 phenotype as reported, showing why it is a genuine differential
      rather than a naming artefact, and where the dental emphasis differs.
  - reference: PMID:33308444
    reference_title: "SCUBE3 loss-of-function causes a recognizable recessive developmental disorder due to defective bone morphogenetic protein signaling."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "We show that SCUBE3 acts as a BMP2/BMP4 co-receptor, recruits the BMP receptor complexes into raft microdomains, and positively modulates signaling possibly by augmenting the specific interactions between BMPs and BMP type I receptors."
    explanation: >-
      Explains the overlap mechanistically: the two disorders reduce the same
      BMP signal from opposite ends of one ligand-co-receptor axis.
- name: Brachydactyly type A2
  disease_term:
    preferred_term: brachydactyly type A2
    term:
      id: MONDO:0007216
      label: brachydactyly type A2
  description: >-
    Brachydactyly type A2 primarily affects the middle phalanges, especially of the second and fifth digits,
    and can arise from BMPR1B or GDF5 variants. Two families carried tandem duplications of 5,895 and
    5,547 bp approximately 110 kb downstream of BMP2. A homologous wild-type mouse sequence drove a limb
    reporter, supporting enhancer activity. Increased or ectopic BMP2 expression from the human duplication
    was proposed, not directly measured. This regional regulatory lesion is distinct from coding BMP2
    loss and whole-gene deletion.
  distinguishing_features:
  - Predominantly digital malformations rather than the multisystem BMP2 haploinsufficiency phenotype
  - A tandem duplication of a downstream regulatory element can underlie BMP2-linked BDA2; BMPR1B and GDF5 are alternative causal genes.
  evidence:
  - reference: PMID:19327734
    reference_title: "Duplications involving a conserved regulatory element downstream of BMP2 are associated with brachydactyly type A2."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our results reveal an additional functional mechanism for the pathogenesis of BDA2, which is duplication of a regulatory element that affects the expression of BMP2 in the developing limb."
    explanation: >-
      Human duplications segregated with BDA2. The full paper separately demonstrated limb enhancer activity
      in mice and proposed, rather than measured, the duplication-induced expression change.
  - reference: PMID:19327734
    reference_title: Duplications involving a conserved regulatory element downstream of BMP2 are associated with brachydactyly type A2.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: These analyses revealed a specific X-Gal staining in the limb buds and the developing phalanges but not in other parts of the embryos
    explanation: >-
      The wild-type homologous sequence drove a reporter in transgenic mice. This does not directly measure
      endogenous BMP2 expression in duplication carriers.
- name: Larger 20p12 contiguous gene deletion syndromes
  description: >-
    Multigene 20p12 deletions can add or modify phenotypes beyond the BMP2-associated core. JAG1 involvement
    is relevant to Alagille syndrome, and deletions including PROKR2 have been reported with hypopituitarism.
    Individual contributions and penetrance require assessment rather than assigning every additional
    feature to a neighboring gene. WPW has also occurred with an intragenic BMP2 truncating variant, so
    it is not restricted to large deletions.
  distinguishing_features:
  - Deletion boundaries and gene content on chromosomal microarray
  - Additional findings confined to multigene deletions require separate causal assessment; variable expressivity can occur within a family.
  evidence:
  - reference: PMID:21671386
    reference_title: "Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Microdeletion 20p13p12 involving BMP2 is rare and has been implicated in Wolff-Parkinson-White (WPW) syndrome with neurocognitive deficits and with Alagille syndrome when the deletion includes the neighboring JAG1 gene in addition to BMP2."
    explanation: >-
      Names the contiguous-gene phenotypes and ties Alagille syndrome
      specifically to JAG1 inclusion rather than to BMP2.
  - reference: PMID:28586151
    reference_title: "A heterozygous microdeletion of 20p12.2-3 encompassing PROKR2 and BMP2 in a patient with congenital hypopituitarism and growth hormone deficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The deletion contained 17 protein coding genes including PROKR2 and BMP2, both of which are expressed during embryological development of the pituitary gland."
    explanation: >-
      A 4.8 Mb deletion in which 17 genes are removed. Cited as the reason
      hypopituitarism in a deletion patient cannot be attributed to BMP2 dose
      alone.
clinical_burden:
  burden_level: MODERATE
  rationale: >-
    Burden varies with skeletal, craniofacial, cardiac and hearing involvement. Reported care includes
    middle-ear procedures, speech support, dental and craniofacial interventions, scoliosis surgery and
    cardiac monitoring or ablation. Published series do not establish life expectancy, and normal cognition
    is not universal across all reported genotypes.
  evidence:
  - reference: PMID:29198724
    reference_title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "display a consistent distinct phenotype characterized by short stature and skeletal and cardiac anomalies without neurological deficits"
    explanation: >-
      The defining cohort described a multisystem malformation phenotype without reported neurological
      deficits. This cohort observation does not establish lifelong cognitive or survival outcomes for
      all affected individuals.
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Delayed speech, secretory otitis media and conductive hearing loss are common features that require medical attention."
    explanation: >-
      Establishes an ongoing, non-trivial care requirement, which is the other
      half of a moderate rather than mild rating.
discussions:
- discussion_id: bmp2_developmental_delay_extent
  kind: KNOWLEDGE_GAP
  prompt: >-
    What is the neurodevelopmental spectrum attributable to isolated BMP2 loss, and how do multigene deletions
    and additional variants modify it?
  status: OPEN
  attaches_to:
  - phenotypes#Delayed speech and language development
  - pathophysiology#BMP2 Haploinsufficiency
  rationale: >-
    The 2017 cohort reported normal cognitive development, whereas later series include speech delay and
    occasional broader developmental concerns. Interpretation is limited by mixed genotypes and incomplete
    formal testing. Relatives carrying the same multigene deletion may differ in developmental outcome;
    this supports variable expressivity and does not exclude a contribution from the deletion. Cohorts
    restricted to intragenic variants or BMP2-only deletions, with standardized assessment, are needed.
  evidence:
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The degree of developmental delay is still controversial."
    explanation: >-
      The controversy stated by the authors of the most recent cohort.
  - reference: PMID:39970956
    reference_title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We propose that global developmental delay is either a rare part or not part of the phenotype."
    explanation: >-
      The 2025 authors propose that global delay is rare or absent from the core phenotype, but this remains
      unresolved.
  - reference: PMID:22965927
    reference_title: "Cleft palate in a multigenerational family with a microdeletion of 20p12.3 involving BMP2."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The father was otherwise healthy with no history of FTT or DD, suggesting high penetrance, yet variable expressivity for haploinsufficiency of BMP2."
    explanation: >-
      Father and son with the same multigene deletion differed in developmental outcome. Such discordance
      does not establish that the deletion is unrelated to the delay.
- discussion_id: bmp2_cardiac_laterality
  kind: KNOWLEDGE_GAP
  prompt: >-
    Does BMP2 contribute to determination of the cardiac axis in humans, beyond
    its established role in septal and valvuloseptal morphogenesis?
  status: OPEN
  attaches_to:
  - pathophysiology#Failed Endocardial Cushion Mesenchymal Transition
  - phenotypes#Congenital heart disease
  rationale: >-
    One family with a BMP2 frameshift variant included a proband with isolated
    dextrocardia and situs solitus, with no other viscus displaced and no
    structural cardiac defect. Laterality is a distinct developmental question
    from cushion transformation, and a single proband cannot separate a real
    BMP2 laterality role from coincidence. The reporting authors say so
    themselves. It is recorded here so that dextrocardia is not silently folded
    into the cardiac-anomaly phenotype, where it would imply a mechanism the
    evidence does not support.
  evidence:
  - reference: PMID:37572998
    reference_title: "BMP2 is a potential causative gene for isolated dextrocardia situs solitus."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In addition to short stature, impaired hearing ability and minor skeletal deformities, the proband exhibited isolated dextrocardia situs solitus without cardiac anomalies and abnormal locations of other visceral organs."
    explanation: >-
      The single observation the question rests on, including that it occurred
      without any structural cardiac defect.
  - reference: PMID:37572998
    reference_title: "BMP2 is a potential causative gene for isolated dextrocardia situs solitus."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "further studies are needed to assemble more cases to elucidate BMP2 role in human heart development"
    explanation: >-
      The authors' own statement that the laterality claim is not established.
notes: >-
  Phenotype frequencies are provisional observations from small, clinically ascertained and sometimes
  related cohorts. A feature reported in one case without an assessed denominator has no assigned frequency.
  Combined table categories such as micrognathia and/or retrognathia do not establish the frequency of
  either component separately. The 2025 tables contain some inconsistencies between summary counts and
  individual cells; these require interpretation rather than automatic aggregation. Neurodevelopmental
  involvement and uncommon endocrine or skeletal findings require attention to deletion extent and additional
  diagnoses. Homozygous tissue-specific and compound BMP mouse knockouts establish developmental requirements
  but are not equivalent to human monoallelic BMP2 loss.
references:
- reference: PMID:29198724
  title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions."
- reference: PMID:39970956
  title: "Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency."
- reference: PMID:40285376
  title: "Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant."
- reference: PMID:37125634
  title: "Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum."
- reference: PMID:33247540
  title: "A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve."
- reference: PMID:10362015
  title: "Bone morphogenetic protein-2 acts synergistically with transforming growth factor-beta3 during endothelial-mesenchymal transformation in the developing chick heart."
- reference: PMID:21671386
  title: "Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate."
- reference: PMID:30413887
  title: "Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice."
- reference: PMID:16314491
  title: "Bmp2 is essential for cardiac cushion epithelial-mesenchymal transition and myocardial patterning."
- reference: PMID:17194222
  title: "Genetic analysis of the roles of BMP2, BMP4, and BMP7 in limb patterning and skeletogenesis."
- reference: PMID:17099713
  title: "BMP2 activity, although dispensable for bone formation, is required for the initiation of fracture healing."
- reference: PMID:19327734
  title: "Duplications involving a conserved regulatory element downstream of BMP2 are associated with brachydactyly type A2."
- reference: PMID:28586151
  title: "A heterozygous microdeletion of 20p12.2-3 encompassing PROKR2 and BMP2 in a patient with congenital hypopituitarism and growth hormone deficiency."
- reference: PMID:37572998
  title: "BMP2 is a potential causative gene for isolated dextrocardia situs solitus."
- reference: PMID:19116164
  title: "Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis."
- reference: PMID:22965927
  title: "Cleft palate in a multigenerational family with a microdeletion of 20p12.3 involving BMP2."
- reference: PMID:33308444
  title: "SCUBE3 loss-of-function causes a recognizable recessive developmental disorder due to defective bone morphogenetic protein signaling."
- reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
  title: "Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC"
variants:
- name: NM_001200.3:c.-7-2_-7-1delAGinsCC
  gene:
    preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  type: splice acceptor dinucleotide replacement
  genomic_contexts:
  - intron
  - 5' UTR
  description: >-
    Variant at the splice acceptor of untranslated intron 1. Two affected sisters inherited it from a
    clinically unaffected mosaic father. Routine blood sequencing was negative in the father, while variant-specific
    testing of other tissues established mosaicism.
  functional_effects:
  - function: RNA splicing
    description: >-
      Patient lymphoblast RNA contains additional products retaining only 61 or 28 nucleotides of exon
      2. A 240-amino-acid truncated protein is predicted; production, function and decay of these transcripts
      were not experimentally resolved.
  evidence:
  - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: a splice-altering variant, c.−7−2_−7−1delAGinsCC, which deletes AG and inserts CC at the splice acceptor site
    explanation: >-
      Identifies the 5-prime untranslated intron 1 splice-acceptor substitution in family 1, reported
      on NM_001200.3.
  - &id001
    reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
    reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: Sanger sequencing of gel-purified PCR products revealed that band 4 contained 61 nucleotides of exon 2, whereas band 5 contained only 28 nucleotides from exon 2
    explanation: >-
      Patient lymphoblast RT-PCR and sequencing identified two additional cryptic splice products. Wild-type
      and naturally alternatively spliced products were also present; protein abundance and nonsense-mediated
      decay were not measured.
- name: BMP2 c.313C>T (p.Arg105Ter)
  gene:
    preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  variant_type: single nucleotide variant
  type: nonsense
  description: >-
    A de novo nonsense variant reported in the patient with bicuspid aortic valve, progressive aortic
    dilatation and WPW. The report does not give a transcript accession for this HGVS notation.
  evidence:
  - reference: PMID:33247540
    reference_title: A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: a de novo BMP2 c.313 C>T (p.R105X) variant in the patient
    explanation: >-
      Reports this sequence variant in the clinical context described.
- name: BMP2 c.440C>G (p.Ser147Ter)
  gene:
    preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  variant_type: single nucleotide variant
  type: nonsense
  description: >-
    A de novo nonsense variant in the single reported patient with phalangeal osteolysis. The cached abstract
    does not specify the transcript accession.
  evidence:
  - reference: PMID:40285376
    reference_title: Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Whole-exome sequencing identified a de novo heterozygous truncating variant (c.440C>G; p.Ser147*)
    explanation: >-
      Reports this sequence variant in the clinical context described.
- name: NM_001200.4:c.217_218dup (p.Val74ProfsTer8)
  gene:
    preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  variant_type: duplication
  type: frameshift
  description: >-
    The intragenic frameshift in Individual 4 of the 2025 cohort; Table 1 reports de novo occurrence.
    The other six individuals had multigene deletions.
  evidence:
  - reference: PMID:39970956
    reference_title: Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: 'one (Individual 4) had a heterozygous two base pair duplication predicted to lead to a frameshift and a premature stop codon (NM_001200.4): c.217_218dup, p.(Val74Profs*8)'
    explanation: >-
      Reports this sequence variant in the clinical context described.
- name: NM_001200.4:c.231dup (p.Tyr78LeufsTer38)
  gene:
    preferred_term: BMP2
    term:
      id: hgnc:1069
      label: BMP2
  variant_type: duplication
  type: frameshift
  description: >-
    Reported in a family whose proband had short stature, hearing impairment and isolated dextrocardia
    with situs solitus. The isolated laterality observation does not establish a recurrent genotype-specific
    phenotype.
  evidence:
  - reference: PMID:37572998
    reference_title: BMP2 is a potential causative gene for isolated dextrocardia situs solitus.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: 'a novel frameshift variant NM_001200.4: c.231dup (p.Tyr78Leufs*38)'
    explanation: >-
      Reports this sequence variant in the clinical context described.
experimental_models:
- name: Patient lymphoblast BMP2 splicing assay
  experimental_model_type: CELL_LINE
  organism:
    preferred_term: Homo sapiens
    term:
      id: NCBITaxon:9606
      label: Homo sapiens
  publication: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
  description: >-
    RT-PCR of lymphoblast RNA and sequencing of isolated amplicons identifies aberrant processing of the
    familial intron 1 splice-acceptor variant.
  modeled_mechanisms:
  - target: BMP2 Haploinsufficiency
    relationship: MEASURES
    fidelity: MODERATE
    description: >-
      RT-PCR of lymphoblast RNA and sequencing of isolated amplicons identifies aberrant processing of
      the familial intron 1 splice-acceptor variant.
    limitations: >-
      Non-skeletal cells establish a transcript-processing defect, not the protein dose or signaling consequence
      in affected embryonic tissues.
    evidence:
    - reference: url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/
      reference_title: Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC
      supports: SUPPORT
      evidence_source: IN_VITRO
      snippet: Sanger sequencing of gel-purified PCR products revealed that band 4 contained 61 nucleotides of exon 2, whereas band 5 contained only 28 nucleotides from exon 2
      explanation: >-
        Patient lymphoblast RT-PCR and sequencing identified two additional cryptic splice products. Wild-type
        and naturally alternatively spliced products were also present; protein abundance and nonsense-mediated
        decay were not measured.
  evidence:
  - *id001
- name: Embryonic head and isolated palate culture rescue
  experimental_model_type: OTHER
  organism:
    preferred_term: Mus musculus
    term:
      id: NCBITaxon:10090
      label: Mus musculus
  publication: PMID:30413887
  description: >-
    E13.5 conditional-mutant heads cultured for 24 hours after tongue and mandible removal recover palatal
    elevation; isolated palatal shelves fuse during 72-hour organ culture.
  modeled_mechanisms:
  - target: Failure of Tongue Descent and Palatal Shelf Elevation
    relationship: PERTURBS
    fidelity: MODERATE
    description: >-
      E13.5 conditional-mutant heads cultured for 24 hours after tongue and mandible removal recover palatal
      elevation; isolated palatal shelves fuse during 72-hour organ culture.
    limitations: >-
      A mechanical rescue in explants from homozygous conditional-null embryos does not establish every
      cause of human BMP2-associated clefting.
    evidence:
    - reference: PMID:30413887
      reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
      supports: SUPPORT
      evidence_source: IN_VITRO
      snippet: similar to the wild-type controls, the palatal shelves of mutants were able to elevate in roller culture (Fig. 3 a-d) and to fuse in organ culture (Fig. 3 e, f).
      explanation: >-
        Rescue after removal of the tongue and mandible supports an extrinsic obstruction to elevation.
  evidence:
  - reference: PMID:30413887
    reference_title: Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: similar to the wild-type controls, the palatal shelves of mutants were able to elevate in roller culture (Fig. 3 a-d) and to fuse in organ culture (Fig. 3 e, f).
    explanation: >-
      Rescue after removal of the tongue and mandible supports an extrinsic obstruction to elevation.
- name: Chick atrioventricular endocardial-myocardial coculture
  experimental_model_type: CO_CULTURE
  organism:
    preferred_term: Gallus gallus
    term:
      id: NCBITaxon:9031
      label: Gallus gallus
  publication: PMID:10362015
  description: >-
    Antisense inhibition of BMP2 suppresses mesenchyme formation in AV endocardium cocultured with myocardium;
    recombinant BMP2 rescues the effect.
  modeled_mechanisms:
  - target: Failed Endocardial Cushion Mesenchymal Transition
    relationship: PERTURBS
    fidelity: MODERATE
    description: >-
      Antisense inhibition of BMP2 suppresses mesenchyme formation in AV endocardium cocultured with myocardium;
      recombinant BMP2 rescues the effect.
    limitations: >-
      This is an avian explant perturbation. Recombinant BMP2 alone did not induce transformation in endothelial
      monolayers, and patient heterozygosity was not modeled.
    evidence:
    - reference: PMID:10362015
      reference_title: Bone morphogenetic protein-2 acts synergistically with transforming growth factor-beta3 during endothelial-mesenchymal transformation in the developing chick heart.
      supports: SUPPORT
      evidence_source: IN_VITRO
      snippet: Antisense oligodeoxynucleotides to BMP2 inhibited mesenchyme formation in AV endocardium cocultured with associated myocardium. This inhibitory effect was reversed by the addition of recombinant BMP2.
      explanation: >-
        Loss and rescue identify a BMP2 contribution in the coculture system.
  evidence:
  - reference: PMID:10362015
    reference_title: Bone morphogenetic protein-2 acts synergistically with transforming growth factor-beta3 during endothelial-mesenchymal transformation in the developing chick heart.
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: Antisense oligodeoxynucleotides to BMP2 inhibited mesenchyme formation in AV endocardium cocultured with associated myocardium. This inhibitory effect was reversed by the addition of recombinant BMP2.
    explanation: >-
      Loss and rescue identify a BMP2 contribution in the coculture system.

📚

References & Deep Research

References

18

PMID:29198724

Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions.

No top-level findings curated for this source.

PMID:39970956

Genotypic and Phenotypic Characterization of Seven Individuals With Predicted Bone Morphogenetic Protein 2 (BMP2) Haploinsufficiency.

No top-level findings curated for this source.

PMID:40285376

Emergence of osteolysis as a new radiological feature in a case with a novel BMP2 gene variant.

No top-level findings curated for this source.

PMID:37125634

Monoallelic loss-of-function BMP2 variants result in BMP2-related skeletal dysplasia spectrum.

No top-level findings curated for this source.

PMID:33247540

A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve.

No top-level findings curated for this source.

PMID:10362015

Bone morphogenetic protein-2 acts synergistically with transforming growth factor-beta3 during endothelial-mesenchymal transformation in the developing chick heart.

No top-level findings curated for this source.

PMID:21671386

Microdeletion 20p12.3 involving BMP2 contributes to syndromic forms of cleft palate.

No top-level findings curated for this source.

PMID:30413887

Conditional deletion of Bmp2 in cranial neural crest cells recapitulates Pierre Robin sequence in mice.

No top-level findings curated for this source.

PMID:16314491

Bmp2 is essential for cardiac cushion epithelial-mesenchymal transition and myocardial patterning.

No top-level findings curated for this source.

PMID:17194222

Genetic analysis of the roles of BMP2, BMP4, and BMP7 in limb patterning and skeletogenesis.

No top-level findings curated for this source.

PMID:17099713

BMP2 activity, although dispensable for bone formation, is required for the initiation of fracture healing.

No top-level findings curated for this source.

PMID:19327734

Duplications involving a conserved regulatory element downstream of BMP2 are associated with brachydactyly type A2.

No top-level findings curated for this source.

PMID:28586151

A heterozygous microdeletion of 20p12.2-3 encompassing PROKR2 and BMP2 in a patient with congenital hypopituitarism and growth hormone deficiency.

No top-level findings curated for this source.

PMID:37572998

BMP2 is a potential causative gene for isolated dextrocardia situs solitus.

No top-level findings curated for this source.

PMID:19116164

Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis.

No top-level findings curated for this source.

PMID:22965927

Cleft palate in a multigenerational family with a microdeletion of 20p12.3 involving BMP2.

No top-level findings curated for this source.

PMID:33308444

SCUBE3 loss-of-function causes a recognizable recessive developmental disorder due to defective bone morphogenetic protein signaling.

No top-level findings curated for this source.

url:https://pmc.ncbi.nlm.nih.gov/articles/PMC5812889/

Monoallelic BMP2 Variants Predicted to Result in Haploinsufficiency Cause Craniofacial, Skeletal, and Cardiac Features Overlapping Those of 20p12 Deletions - PMC

No top-level findings curated for this source.

Deep Research

1

Deep research results are used as seeds for research; they do not undergo the same validation as the main records and may contain errors. How we use deep research.

Evaluations and curation notes (3)

Review BMP2 clinical evidence and distinguish human haploinsufficiency from knockout models · 2026-09-27T14:24:11Z · View source

Reviewed the original KB, all five prior histories, the matching deep-research narrative and citation sidecar, and the available primary sources. Eligibility: Mendelian BMP2 disorder, no prior REVIEW, outside infectious/environmental exclusions. Rebased onto origin/main at da303fc58b617d298f5e207c56fb6cb20498b463 before edits. Eight-dimension assessment: 1. Phenotypes: adequate after expansion from 32 to 53 entries. Recovered human rib, airway, skeletal-maturation, spine, facial, dental and cardiac findings from the 2017 full text and 2025 tables. Added 21 phenotypes. Removed frequency bands inferred from single cases or unspecified denominators. Combined table categories do not establish the frequency of each component. The 2025 hearing and scapula summary counts disagree with individual table cells, so no precise frequency is assigned to those features. 2. Subtypes: no established BMP2 molecular subtypes were identified. Kept SCUBE3-related SSFSC2, regulatory-duplication-associated BDA2 and larger contiguous deletions as differentials. The 2025 31-gene deletion case (PMID:41282487) does not justify assigning seizures or metabolic findings to isolated BMP2 loss. 3. Pathophysiology: adequate after correction. Replaced generic/other-disease signaling support with measured mandibular pSmad1/5/8 and pp38 results from PMID:30413887. Added separate p38 and neural crest chondrogenic-progenitor nodes. Removed the inappropriate migratory cranial neural crest cell binding. Complete lineage-specific and combined Bmp2/Bmp4 knockouts do not establish the magnitude of human haploinsufficiency, universal compensation, or a severity upper bound. Scoped limb chondrogenesis results, cardiac cushion findings, mechanical palate rescue and the speculative human osteolysis link. Corrected failed dorsal cervical vertebral fusion, which had been described as excessive fusion. Retained negative heterozygote long-bone and mechanical readouts. Added three experimental systems for patient RNA, palate rescue and chick AV coculture. 4. Treatments/trials: adequate for available clinical evidence. Added reported cardiac ablation, physical/occupational therapy, mandibular distraction and scoliosis surgery. Growth hormone response remains a single multigene-deletion observation; another cohort patient received GH despite normal testing. No disease-modifying efficacy is inferred. ClinicalTrials.gov API v2 returned HTTP 200 and zero studies for the condition queries '"BMP2-related"', '"BMP2 haploinsufficiency"', and '"short stature facial dysmorphism"' on 2026-09-27. These bounded searches do not claim that no broader BMP2-related trial exists. 5. Genetics: adequate. Captured five representative splice/nonsense/frameshift variants, the somatic and germline paternal mosaicism finding, negative routine blood sequencing followed by variant-specific testing in other tissues, and patient RNA splice products. Nonsense-mediated decay and an exact 50% secreted ligand reduction were not measured. In the BDA2 differential, full-text PMID:19327734 shows reporter enhancer activity but only proposes increased or ectopic endogenous BMP2 expression from the duplication. 6. Diagnostics: adequate. Retained sequence/CNV diagnosis, endocrine and hearing evaluation; added ECG and echocardiographic follow-up. A case's annual echocardiography is not a universal interval. Removed unsupported assertions about normal cognition, normal lifespan and progression/onset of osteolysis. Discordance among relatives with the same deletion does not exclude a deletion contribution to developmental delay. 7. References: consumed the full scientific text, tables and available figure/supplement captions of the major cached sources, including PMID:19116164, 17194222, 30413887, 21671386, 22965927, 33247540 and 39970956. Recovered the 2017 defining paper through its PMC URL using just fetch-reference when PMID fetching returned only the abstract; its generated HTML cache is included. Refetch recovered full PMID:19327734 and the missing 2025 tables. PMID:37125634 publisher HTML/PDF retrieval returned 403; PMID:16314491 and 40285376 remain abstract-only. No GeneReviews chapter matched the repository Bookshelf index dated 2026-09-10. Searches of all cited cached texts found no GEO/SRA/ArrayExpress/PRIDE or NCT accessions to curate; this does not assert no unexamined repository record exists. No retired dataset-accession blob was read or restored. 8. Overall consumption: central genetic, clinical and mechanistic themes are covered. Other-gene mechanisms and multigene-deletion-specific metabolic/neurological claims were not imported as BMP2 causation. The newer cartilage/EGFR study was a secondary mechanistic lead, not necessary to establish the directly documented neural crest chondrogenic defect; its unused cache is excluded. All added evidence items carry source titles. Snippets are exact cached passages, with explicit ellipses where HTML markup interrupts table rows or italic gene names. Caches were generated exclusively with just fetch-reference. Validation: authoritative just validate-disorders passed schema, terms and all 155 snippets/173 titles, with zero skipped/unavailable references or issues. Entity and causal target checks, coarse-binding checks and snippet boundaries passed. History schema passed. All four whole-repository evidence ratchets passed: snippet length, grading, title snippets and reference titles. Pre-commit formatters were applied and parsed YAML semantic equivalence verified; codespell passed.

Review round: act on red-team findings and integrate deep-research report · 2026-09-05T07:59:19Z · View source

Pre-PR red-team review (dismech-pr-review skill, fresh-context subagent) plus integration of the deep-research report that landed after the first commit. Five blocking findings fixed. First, scoliosis was removed as a phenotype and as a causal edge: across every reference cached for this entry the word appears exactly once, inside a sentence about JAG1 deletions and Alagille syndrome in PMID:21671386, which is a contiguous-gene phenotype this entry excludes elsewhere. That was the single Named Entity Confusion escape and it is now recorded in notes so it is not reintroduced. Second, the chondrogenesis node misrepresented PMID:17194222: its chondrocyte-differentiation DECREASED annotation is contradicted by that paper, which reports chondrogenic differentiation proceeds normally without BMP2, and its osteogenesis finding is from a compound Bmp2/Bmp4 knockout rather than BMP2 alone. The node was renamed Reduced Osteogenic Output of Skeletal Progenitors, rebound to osteoblast differentiation, the compound-knockout qualification stated in the explanation, and the contrary result added as an explicit REFUTE item. Third, brachydactyly was over-graded from a single figure legend; real hand data (short fifth fingers segregating through three generations of the BMP2-only deletion family) was added from PMID:21671386. Fourth, two nodes bundled multiple mechanistic steps: the craniofacial node was split into Craniofacial Skeletal Hypoplasia and Failure of Tongue Descent and Palatal Shelf Elevation, which also let the entry record PMID:30413887's measured negative results, that BMP/SMAD activity is largely preserved in the mutant palate through BMP4 and BMP7 redundancy and that BMP2 is not an intrinsic regulator of shelf elevation. Fifth, the deep-research report is now present. Important fixes: frequency bands removed from six craniofacial phenotypes whose only source is a three-patient photographic figure legend; homozygosity caveats added to four causal-edge explanations that rest on homozygous conditional mouse mutants; the SCUBE3 evidence item now names SSFSC2 explicitly because its quoted phrase 'the human disorder' means the sibling entity; hypotonia rebound from HP:0001319 Neonatal hypotonia to HP:0008947 Floppy infant since both sources describe infancy; myringotomy and adenoidectomy rebound from generic NCIT:C15329 to NCIT:C70906 and NCIT:C51697; ten orphaned phenotypes connected to the pathograph, leaving two deliberately unconnected because no source proposes a mechanism; module-expected GO terms added to both conforming nodes; congenital heart disease frequency removed for want of a denominator and its arrhythmia claim reconciled with the entry's own Wolff-Parkinson-White exclusion. Minor fixes: better short-stature snippet carrying the actual 6/7 count, cranial neural crest cell rebound to CL:0000008, MONDO:0007216 added to the brachydactyly type A2 differential with a note that BMPR1B and GDF5 are the commoner causes, bone remodeling GO term added, speech therapy joined to the pathograph, and an unverifiable Cre-driver genotype softened to what the cached source supports. Deep research: the requested falcon provider returned 403 and the run fell back to openscientist, recorded in the report frontmatter. Reference validation 16/16 resolved, zero confabulations, one off-topic flag (PMID:24022823, not used). Term validation found 0 of 11 checked terms named correctly, so none of the report's ontology suggestions were adopted; one offered UBERON:0006618 for growth plate, which is the atrium auricular region. Two of its citations were adopted after reading them: PMID:19116164 for BMP2 dosage sensitivity, which supplies the dose claim the compound limb knockout does not, and PMID:22965927 for a second multigenerational deletion family that independently replicates the clefting phenotype and gives a second within-family developmental-delay discordance. Validation after changes: just validate-disorders passes with 92/92 snippets verified, term validation passes, and check-entity-refs, check-causal-targets, check-duplicate-keys, check-qualifier-terms, check-enum-values, check-folded-hyphens, check-snippet-length, check-title-snippets and check-snippet-grading all pass. Compliance 89.3 percent, down from 91.7 because the denominator grew with the added nodes and evidence.

Create: BMP2-Related Short Stature-Facial Dysmorphism-Skeletal Anomalies Syndrome · 2026-09-05T07:32:53Z · View source

Created MONDO:0100297 (SSFSC1, OMIM 617877, BMP2 haploinsufficiency) from the curation stub, which is deleted in the same change. Deep research: falcon was requested but its EDISON_API_KEY returns 403 (providers --check reports UNREACHABLE); the run was re-issued with --fallback so the substitution is recorded by the run rather than chosen by hand. The entry as committed is built from primary literature retrieved directly via the PubMed E-utilities API, not from a deep-research report. Anchors: PMID:29198724 (defining 12-patient series), PMID:39970956 (2025 seven-patient cohort, full text cached), PMID:21671386 (20p12.3 deletion cleft palate series), PMID:40285376 (osteolysis case), plus mechanism sources PMID:30413887 (Wnt1-Cre cranial neural crest conditional KO), PMID:17194222 (limb BMP2/4/7 genetics), PMID:16314491 (AV cushion EMT), PMID:17099713 (fracture-healing requirement), PMID:19327734 (BDA2 enhancer duplication), PMID:33308444 (SCUBE3 as BMP2 co-receptor), PMID:28586151 and PMID:37572998 (contiguous-gene and laterality caveats). No GeneReviews chapter exists for BMP2 or SSFSC1; PubMed searches for both returned nothing, and the absence is recorded in the entry notes. Named Entity Confusion was the main hazard and was handled explicitly: MONDO:0100297 (SSFSC1) versus MONDO:0030953 (SSFSC2, SCUBE3) differ only by a trailing digit and are separated by OMIM number throughout; brachydactyly type A2 is a BMP2 enhancer duplication and therefore mechanistically opposite; and Alagille/JAG1, hypopituitarism/PROKR2 and Wolff-Parkinson-White are contiguous-gene phenotypes of larger 20p12 deletions. All three are curated as differential diagnoses rather than as BMP2 phenotypes. No datasets curated: just discover-datasets returned 12 candidates, all GENE_ONLY with zero DIRECT, the top hit being a glioma cell line treated with recombinant BMP2; the negative result is recorded in notes. Two module conformances declared against pharyngeal_arch_patterning_serial_homology (trigger and consequence nodes); its central-effector node is deliberately not claimed because it is written around arch-identity mis-specification, which BMP2 does not show. Validation: just validate passes, just validate-disorders passes with 84/84 snippets verified against the cached references, term validation passes, and check-entity-refs, check-causal-targets, check-duplicate-keys, check-qualifier-terms, check-enum-values, check-snippet-length, check-title-snippets, check-snippet-grading and check-folded-hyphens all pass. linkml-data-qc reports 91.7 percent global compliance.

OpenScientist ▸

1. Disease Information

openscientist-autonomous 20 citations 2026-09-05T08:01:28.382904

1. Disease Information

Overview. SSFSC1 is a Mendelian multiple-congenital-anomaly / dysmorphism syndrome caused by BMP2 haploinsufficiency. It was formally delineated as a single nosological entity by Tan et al. in 2017, who reported 12 individuals from 8 unrelated families carrying monoallelic truncating/frameshift/splice BMP2 variants or 20p12.3 deletions and sharing "features of short stature, a recognizable craniofacial gestalt, skeletal anomalies, and congenital heart disease" (PMID: 29198724).

Key identifiers.

Resource	Identifier
OMIM (disease)	#617877 — "Short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 1"
MONDO	MONDO:0100297
Gene	*BMP2* — OMIM 112261; HGNC:1069; NCBI Gene 650; UniProt P12643; Ensembl ENSG00000125845; locus 20p12.3*
Allelic disorder	Brachydactyly type A2 (BDA2), OMIM #112600
ICD-11	Best mapped to structural developmental-anomaly categories; no unique code
ICD-10	No specific code (grouped under Q87.x multiple-anomaly syndromes)

Synonyms / alternative names: SSFSC syndrome; SSFSC1; BMP2-related skeletal dysplasia spectrum; BMP2 haploinsufficiency; 20p12.3 microdeletion syndrome (BMP2-related, when deletion is the mechanism).

Source of information. The knowledge base for this disease is derived from aggregated disease-level resources (OMIM, Orphanet, MONDO) and from individual-patient case series published in the primary literature (Tan 2017; Priestley 2023; Stavrén-Eriksson 2025; plus single/small case reports). There is no EHR-scale or population-registry dataset for this ultra-rare condition.

2. Etiology

Primary cause — genetic. SSFSC1 is a monogenic disorder caused by reduced BMP2 dosage. Two mechanistic classes converge on the same haploinsufficient state:

Intragenic loss-of-function variants — truncating (nonsense), frameshift, splice-altering, and (functionally validated) missense variants. Example ClinVar/literature variants: NM_001200.4:c.460C>T (p.Arg154Ter); c.231dup (p.Tyr78Leufs*38).
Contiguous gene deletions — 1.3–5.5 Mb 20p12 deletions encompassing BMP2 (PMID: 29198724; PMID: 39970956).

Tan et al. concluded that "haploinsufficiency of BMP2 could be the primary phenotypic determinant in individuals with predicted truncating variants and deletions encompassing BMP2" (PMID: 29198724). Missense variants were later shown to be LOF by modeling in zebrafish (PMID: 37125634).

Genetic risk factors. The causal variant is the risk factor; there are no established susceptibility loci or modifier genes with proven effect on SSFSC1 expression. The wide inter- and intrafamilial variability suggests as-yet-unidentified genetic and/or stochastic modifiers.

Environmental risk factors. None identified. There is no evidence for toxin, teratogen, infection, or lifestyle contribution to disease occurrence. (Note: BMP2/SMAD1-5-8 biology is modulated by estrogen and hyperglycemia in unrelated disease models — e.g., vascular calcification [PMID: 32089109] and diabetic-pregnancy growth-plate effects [PMID: 34934622] — but these are not implicated in SSFSC1.)

Protective factors / gene-environment interactions. No genetic protective alleles or gene-environment interactions are documented for this disorder. This is expected for a highly penetrant dominant developmental syndrome.

3. Phenotypes

The phenotype spans four core domains plus an expanded spectrum. Frequencies below are qualitative or drawn from the small published cohorts (Tan 2017, n=12; Priestley 2023, n=18; Stavrén-Eriksson 2025, n=7).

Craniofacial (physical manifestations / clinical signs)

Recognizable gestalt: broad forehead with bitemporal narrowing, flat/retruded midface, short nose with anteverted nares, long philtrum, thin upper lip, crowded dentition, high-arched or cleft palate, micrognathia; Pierre-Robin sequence in some. Onset congenital; highly penetrant with variable severity. - Suggested HPO: HP:0000337 (broad forehead), HP:0011800 (midface retrusion), HP:0000463 (anteverted nares), HP:0000343 (long philtrum), HP:0000219 (thin upper lip vermilion), HP:0000175 (cleft palate), HP:0000347 (micrognathia), HP:0000201 (Pierre-Robin sequence).

Growth (physical manifestation)

Proportionate short stature, non-endocrine in most, congenital/early-childhood onset. Growth-hormone evaluation is recommended in some cases. - Suggested HPO: HP:0004322 (short stature), HP:0003508 (proportionate short stature).

Skeletal (clinical signs / imaging)

Fifth-ray brachydactyly (short fifth-digit proximal phalanges) and clinodactyly; 11 pairs of ribs (axial patterning defect); sandal gap; scoliosis, hip dysplasia/coxa vara, and osteopenia reported in expanded cohorts. - Suggested HPO: HP:0009237 (short 5th finger), HP:0004209 (clinodactyly of 5th finger), HP:0000921 (rib abnormality / 11 pairs of ribs), HP:0001177 (sandal gap), HP:0002650 (scoliosis), HP:0001385 (hip dysplasia), HP:0000938 (osteopenia).

Cardiac (physical manifestations / clinical signs)

Congenital heart disease in ~4/12 in the delineating series, predominantly outflow-tract lesions: transposition of the great arteries, pulmonary valve stenosis, Ebstein anomaly, ventricular septal defect; expanded reports add bicuspid aortic valve with aortic root/ascending aortic aneurysm (PMID: 33247540) and isolated dextrocardia (situs solitus) (PMID: 37572998). Arrhythmias (Wolff-Parkinson-White, paroxysmal SVT, palpitations) in 3/12. - Suggested HPO: HP:0001631 (VSD), HP:0001642 (pulmonary valve stenosis), HP:0001680 (coarctation/great-artery anomaly), HP:0010316 (Ebstein anomaly), HP:0001647 (bicuspid aortic valve), HP:0002616 (aortic root aneurysm), HP:0001696 (dextrocardia), HP:0011675 (arrhythmia).

Expanded spectrum (later cohorts)

Neural tube defects, structural brain anomalies, endocrinopathies (including a patient with hypercalcemia, hypercalciuria, nephrolithiasis, hypophosphatemia, suppressed PTH); secretory otitis media (4/5) with conductive hearing loss; delayed language development (4/5). Global/intellectual developmental delay is not a core feature (PMID: 37125634; PMID: 39970956). - Suggested HPO: HP:0012443 (structural brain anomaly), HP:0045005 (neural tube defect), HP:0000405 (conductive hearing impairment), HP:0000388 (otitis media), HP:0000750 (delayed speech and language development).

Quality-of-life impact. No formal EQ-5D/SF-36/PROMIS data exist. Functional impact is driven mainly by feeding/airway compromise from cleft palate/Pierre-Robin in infancy, hearing loss affecting language, cardiac morbidity, and orthopedic issues; overall cognition and independence are typically preserved.

4. Genetic / Molecular Information

Causal gene. BMP2 (Bone Morphogenetic Protein 2), the sole causal gene. HGNC:1069; NCBI Gene 650; UniProt P12643; OMIM *112261; 20p12.3.

Pathogenic variants.

Feature	Detail
Variant types	Nonsense, frameshift, splice-site, missense (all LOF); whole-gene deletions
Classification	Pathogenic / likely pathogenic per ACMG/AMP (predicted LOF in a haploinsufficient gene = PVS1-supporting)
Example variants	c.460C>T (p.Arg154Ter); c.231dup (p.Tyr78Leufs*38)
Population frequency	Absent/ultra-rare in gnomAD (as expected for a highly penetrant dominant LOF)
Origin	Germline; de novo or inherited; germline (paternal) mosaicism documented
Functional consequence	Loss of function → haploinsufficiency (reduced ligand dosage)

Missense pathogenicity was validated functionally: "Missense variants modeled in zebrafish resulted in loss of protein function" (impaired bmp2b-driven embryonic ventralization) (PMID: 37125634).

Modifier genes / epigenetics. None established. Variable expressivity implies modifiers exist but they are uncharacterized. No disease-specific DNA-methylation or histone-modification signature is described.

Chromosomal abnormalities. 20p12 microdeletions (1.3–5.5 Mb) encompassing BMP2 are a recognized cause; detected by chromosomal microarray/karyotype (PMID: 21671386; PMID: 22965927; PMID: 39970956).

Dosage sensitivity (key concept). OMIM links two reciprocal, allelic BMP2 entities: haploinsufficiency → SSFSC1 (#617877) and duplication of a downstream cis-regulatory element (~110 kb 3′ of BMP2) → BDA2 (#112600). The gene tolerates reduced but not absent dosage in humans (heterozygotes viable; complete loss embryonic-lethal in mouse) (PMID: 37125634; PMID: 29198724).

5. Environmental Information

No environmental, lifestyle, or infectious factors contribute to SSFSC1. It is a purely genetic developmental disorder. This section is not applicable except to note the negative: no toxin, radiation, occupational exposure, diet, or pathogen has been implicated in causation or triggering.

6. Mechanism / Pathophysiology

Causal chain (initiating lesion → clinical manifestation)

A heterozygous LOF BMP2 variant (truncating/frameshift/splice/missense) or a 20p12 deletion removes one functional BMP2 allele → leads to ~50% reduction in secreted BMP2 ligand (haploinsufficiency).
Reduced BMP2 ligand results in attenuated binding to BMP type I/II receptors → leads to reduced phosphorylation of the canonical effectors SMAD1/5/8 (with reduced non-canonical MAPK/p38 signaling as an inferred parallel branch).
Attenuated SMAD1/5/8 output reduces transcription of BMP2 target genes in multiple developing tissues simultaneously (the mechanism then branches by tissue):

Branch A — Skeleton/growth plate: Reduced BMP2 signaling impairs growth-plate chondrocyte maturation/hypertrophy (cross-talk with EGFR, Wnt/β-catenin, IHH, and IGF-I) → results in disordered endochondral ossification → proportionate short stature and skeletal anomalies (fifth-ray brachydactyly, 11 rib pairs; the last also reflecting an axial patterning defect).

Branch B — Craniofacial: Reduced BMP2 during palatogenesis and midface development → leads to cleft/high-arched palate, midface retrusion, and the recognizable facial gestalt (Pierre-Robin sequence in some).

Branch C — Heart: Reduced BMP2 in myocardium overlying the AV canal/outflow tract impairs endocardial-cushion EMT and valvuloseptal morphogenesis, and (via BMP-2/4) impairs neural-crest migration into the outflow tract to form the aortopulmonary septum → results in outflow-tract/septal defects, valve anomalies (including BAV → aortic aneurysm), Ebstein anomaly, and, via disturbed left-right/axis cues, dextrocardia; arrhythmia (WPW/SVT) is a downstream consequence of abnormal conduction-tissue/AV-junction development.

Wide inter-individual variability (same variant, different severity) is inferred to reflect stochastic developmental noise plus unidentified genetic modifiers, since no genotype-phenotype correlation has been demonstrated.

Supporting molecular detail

Molecular pathway. BMP2 is a TGF-β superfamily ligand signaling through BMP type I/II serine-threonine kinase receptors to SMAD1/5/8. Chen, Zhao & Mundy: "Smad1, 5 and 8 are the immediate downstream molecules of BMP receptors and play a central role in BMP signal transduction," and "BMP signaling plays critical roles in heart, neural and cartilage development" (PMID: 15621726). Suggested pathway/GO terms: GO:0030509 (BMP signaling pathway), GO:0071773 (cellular response to BMP stimulus).

Cardiac cushion / neural-crest mechanism. BMP2 is expressed in myocardium overlying the AV canal and OFT cushions and is required for endothelial-to-mesenchymal transformation (EMT). Yamagishi et al.: antisense BMP2 inhibited AV mesenchyme formation (rescued by recombinant BMP2), and "BMP2 … plays an important role in the formation of endocardial cushion tissue and … acts synergistically with TGFbeta3 in the regulation of this developmental event" (PMID: 10362015). Abdelwahid et al. localized Bmp-2 to AV canal/junctional myocardium and maturing valves (PMID: 11512673). Allen et al.: "BMP-2/4 function is required for the migration of neural crest cells into the developing OFT to form the aortopulmonary septum" (PMID: 11412030). Dyer et al. confirmed BMP2 canonical SMAD/Sox9 regulation fine-tunes cushion EMT (PMID: 26418455). Suggested terms: GO:0003198 (epithelial-to-mesenchymal transition involved in endocardial cushion formation), GO:0003203 (endocardial cushion morphogenesis), CL:0002350 (endocardial cell), CL:0000333 (migratory neural crest cell), UBERON:0002062 (endocardial cushion), UBERON:0004145 (cardiac outflow tract).

Growth-plate mechanism. Lees-Shepard et al.: "Signals from the epidermal growth factor receptor (EGFR), and from bone morphogenetic protein-2 (BMP2), are required for normal chondrocyte maturation" (PMID: 34773433). BMP2 promotes chondrocyte hypertrophy with Wnt/β-catenin ("chondrocyte maturation, possibly involving a bone morphogenic protein 2 (BMP2)-mediated mechanism," PMID: 22508079) and IHH, and augments IGF-I anabolic action: "both BMP-2 and BMP-9 augmented the mitogenic action of IGF-I" (PMID: 17549388). COX-2 cross-talk fine-tunes hypertrophy (PMID: 22183916). Suggested terms: GO:0001958 (endochondral ossification), GO:0003413 (chondrocyte differentiation involved in endochondral bone morphogenesis), CL:0000138 (chondrocyte), CL:0000743 (hypertrophic chondrocyte), UBERON:0002515 (growth plate of bone).

Cell types / compartments. Chondrocytes (reserve/prehypertrophic/hypertrophic), endocardial/endothelial cells undergoing EMT, cardiac neural crest cells, palatal mesenchyme. Signaling is transmembrane-receptor → cytoplasmic SMAD → nucleus (GO:0005634) for transcriptional output; ligand is secreted (GO:0005576, extracellular region).

7. Anatomical Structures Affected

Organ level. - Primary: skeleton (long bones/growth plates, ribs, digits, spine, hips), craniofacial complex (palate, midface, mandible), heart (outflow tract, valves, septa, conduction system). - Secondary: middle ear (secretory otitis media → conductive hearing loss); brain/neural tube (structural anomalies in a subset); kidney (nephrolithiasis in an endocrinopathy case); endocrine axes. - Body systems: musculoskeletal, cardiovascular, craniofacial/orofacial, auditory, nervous, endocrine.

Suggested UBERON: UBERON:0002481 (bone tissue), UBERON:0002515 (growth plate), UBERON:0002228 (rib), UBERON:0002389 (manual digit), UBERON:0001716 (secondary palate), UBERON:0000948 (heart), UBERON:0004145 (cardiac outflow tract), UBERON:0002062 (endocardial cushion), UBERON:0001756 (middle ear).

Tissue/cell level. Connective/skeletal (cartilage, bone), cardiac (myocardium, endocardium, valve mesenchyme), neural crest–derived tissues. Cell Ontology: CL:0000138 (chondrocyte), CL:0000746 (cardiac muscle cell), CL:0000333 (neural crest cell).

Subcellular level. Signaling nodes at plasma membrane receptor (GO:0005886), cytoplasm/nucleus for SMAD shuttling (GO:0005634), and the extracellular region for the secreted ligand (GO:0005576).

Localization / lateralization. Skeletal and cardiac defects are typically bilateral/midline (palate, septa) though laterality defects (dextrocardia, situs) reflect disturbed left-right axis determination; digit anomalies are usually bilateral.

8. Temporal Development

Onset: Congenital / prenatal (structural anomalies form during embryogenesis); recognized at birth or early childhood. Onset pattern is developmental/insidious rather than acute.
Progression: The malformations are largely static/structural (fixed at birth), but several features are age-progressive or age-emergent: short stature manifests over the growth years; scoliosis/hip issues and osteopenia can progress; aortic root dilatation associated with BAV can progress and requires monitoring; arrhythmias may present later; hearing loss and language delay emerge in early childhood.
Disease course: Chronic/lifelong but non-degenerative for most core features; no relapsing-remitting pattern.
Critical periods / windows for intervention: Infancy for airway/feeding (cleft palate/Pierre-Robin), early childhood for hearing and language surveillance, and lifelong cardiac/orthopedic monitoring.

9. Inheritance and Population

Inheritance. Autosomal dominant. Tan et al. observed "De novo occurrence and autosomal-dominant inheritance of variants, including paternal mosaicism in two affected sisters who inherited a BMP2 splice-altering variant … across all reported families" (PMID: 29198724) — documenting de novo events, vertical transmission, and germline (paternal) mosaicism relevant to recurrence-risk counseling.

Penetrance / expressivity. High penetrance with variable expressivity: "suggesting high penetrance, yet variable expressivity for haploinsufficiency of BMP2" (PMID: 22965927). No genotype-phenotype correlation established. No genetic anticipation (not a repeat-expansion disorder).

Epidemiology. Ultra-rare. Approximately 40+ patients reported cumulatively (Tan 2017 n=12; single/small reports ~4; Priestley 2023 n=18; Stavrén-Eriksson 2025 n=7). No established prevalence or incidence figures. No strong sex bias, founder effect, or geographic clustering reported. Consanguinity is not relevant (dominant disorder). Carrier frequency is not applicable in the recessive sense; affected parents transmit at 50% risk.

10. Diagnostics

Molecular diagnosis is definitive and requires two complementary approaches, because both small variants and CNVs cause disease:

Sequence analysis of BMP2 (NM_001200.4) via exome/genome or targeted testing → detects truncating/frameshift/splice/missense variants (e.g., c.460C>T p.Arg154Ter; c.231dup p.Tyr78Leufs*38).
Copy-number analysis — chromosomal microarray (CMA) or karyotype → detects 1.3–5.5 Mb 20p12 deletions.

(PMID: 29198724; PMID: 39970956)

Supporting clinical evaluations (phenotype-driven): echocardiography + ECG (outflow-tract defects, BAV/aortic root, WPW/arrhythmia); skeletal and spine radiographs (rib count, brachydactyly, scoliosis, hip dysplasia/coxa vara); bone densitometry (osteopenia); growth charting ± GH-axis evaluation; audiology and tympanometry (secretory otitis media, conductive loss); language/developmental assessment; brain/spine imaging and metabolic/endocrine work-up where indicated (a patient had hypercalcemia, hypercalciuria, nephrolithiasis, hypophosphatemia, suppressed PTH).

Clinical criteria / differential diagnosis. No formal consensus diagnostic criteria; diagnosis rests on the recognizable gestalt plus molecular confirmation. Differential diagnoses include other short-stature/dysmorphism/brachydactyly syndromes such as autosomal-dominant Robinow syndrome (PMID: 32256301) and BDA2 caused by BMPR1B/GDF5/BMP2-regulatory duplication (PMID: 33486847); distinguishing features are the specific BMP2 variant/deletion and the combination of 11 rib pairs, fifth-ray brachydactyly, and outflow-tract cardiac disease.

Screening. Cascade genetic testing of at-risk relatives once a familial variant is identified. Prenatal/preimplantation testing feasible when the familial variant is known. No population newborn screening exists.

11. Outcome / Prognosis

Survival / life expectancy. Generally normal life expectancy with appropriate management; no disease-specific mortality rate is established. The main mortality risk driver is severe congenital heart disease/aortic complications in the subset with cardiac involvement.

Morbidity / function. Morbidity is driven by cleft palate/airway issues in infancy, cardiac disease and arrhythmia, orthopedic problems (scoliosis, hip dysplasia), hearing loss, and short stature. Cognition is typically normal; global developmental delay is not a core feature (PMID: 39970956). No standardized QoL data.

Complications. Feeding/airway compromise (Pierre-Robin), progressive aortic root dilatation with BAV, arrhythmias (WPW/SVT), conductive hearing loss and its effect on language, nephrolithiasis in endocrinopathy cases.

Prognostic factors. Severity of cardiac malformation and presence of aortic aneurysm are the principal determinants of serious outcomes. No molecular prognostic biomarker exists, and absence of genotype-phenotype correlation limits prediction.

12. Treatment

There is no disease-specific or curative therapy; management is symptomatic, anticipatory, and multidisciplinary. Priestley et al. explicitly recommended this framework: "We use this expansion of reported phenotypes to suggest multidisciplinary medical monitoring and management of patients with BMP2-related skeletal dysplasia spectrum" (PMID: 37125634).

Domain	Intervention	NCIT suggestion
Craniofacial	Cleft palate repair; airway/feeding management for Pierre-Robin	Cleft Palate Repair
Cardiac	Surgical correction of structural defects; aortic surveillance/repair; arrhythmia management (ablation/medication)	NCIT Cardiac Surgery
Orthopedic	Scoliosis/hip management; physical therapy	NCIT Orthopedic Surgery
ENT/Audiology	Tympanostomy tubes for secretory otitis media; hearing aids	NCIT Myringotomy
Speech/Development	Speech-language therapy	NCIT:C15192 (Speech Therapy)
Growth	Consider GH evaluation/therapy in selected cases	NCIT Growth Hormone Therapy
Genetics	Genetic counseling (AD, 50% transmission; fertility unaffected)	NCIT:C15266 (Genetic Counseling)

Stavrén-Eriksson et al. specifically recommended surveillance additions: "we propose that evaluation of language development and regular controls of the middle ear should be included in the surveillance of these individuals" (PMID: 39970956).

Advanced/experimental therapeutics, pharmacogenomics. None specific to SSFSC1; no gene/cell/RNA therapy trials. No pharmacogenomic considerations beyond standard care of individual complications.

13. Prevention

Primary prevention: Not applicable to disease occurrence (genetic, largely de novo). Preventive value lies in reproductive counseling: for affected parents, 50% transmission risk; for families with an affected child and apparently unaffected parents, recurrence risk is low but non-zero due to demonstrated germline mosaicism (PMID: 29198724).
Secondary prevention: Cascade testing of relatives; prenatal/PGT when the familial variant is known; early echocardiography/audiology/growth surveillance to enable early intervention.
Tertiary prevention: Anticipatory organ-system surveillance to prevent complications (aortic monitoring, arrhythmia detection, hearing/language support, orthopedic care).
Genetic counseling is the central preventive intervention. Immunization, public-health/environmental measures, and prophylactic medication are not applicable.

14. Other Species / Natural Disease

Taxonomy / orthologs: BMP2 is deeply conserved. Mouse Bmp2 (NCBI Gene 12156), zebrafish bmp2b (used to validate human missense LOF), chick Bmp2 (developmental studies). NCBI Taxon: Mus musculus (10090), Danio rerio (7955), Gallus gallus (9031).
Natural disease / veterinary relevance: No naturally occurring companion-animal or wildlife equivalent of SSFSC1 is catalogued (no specific OMIA entry mirroring this syndrome identified in this investigation).
Comparative biology / conservation: BMP2's roles in endocardial cushion EMT, outflow-tract septation, and chondrocyte maturation are conserved across chick, mouse, and zebrafish, providing strong cross-species mechanistic validation (PMID: 10362015; PMID: 11512673; PMID: 11412030).
Transmission / zoonosis: Not applicable (non-infectious genetic disorder).

15. Model Organisms

Model	Type	Key finding	Recapitulation	PMID
Bmp2 heterozygous knockout mouse	Mammalian, germline	Short stature + skeletal anomalies	Recapitulates growth/skeletal domains of human syndrome	29198724
Bmp2 homozygous null mouse	Mammalian	Embryonic lethal	Confirms dosage sensitivity; cannot model postnatal disease	29198724
Cartilage-conditional Bmp2 loss (Col2-Cre) mouse	Mammalian, conditional	BMP2 required for chondrocyte maturation; EGFR cross-talk	Models growth-plate mechanism	34773433
Zebrafish bmp2b ventralization assay	Vertebrate, in vivo functional	Human missense variants cause LOF	Validates variant pathogenicity	37125634
Chick/mouse embryo heart (in situ, antisense, noggin misexpression)	Developmental	BMP2 drives cushion EMT and OFT neural-crest septation	Models cardiac branch	10362015; 11412030

Model limitations. The heterozygous mouse captures growth/skeletal phenotypes but the full human craniofacial gestalt and the variable cardiac/laterality spectrum are incompletely modeled; homozygous lethality prevents study of complete loss postnatally. Resources: MGI (mouse Bmp2), ZFIN (bmp2b).

Mechanistic Model / Interpretation

 Heterozygous BMP2 LOF variant  OR  20p12 deletion (encompassing BMP2)
          │
          ▼
~50% reduction in secreted BMP2 ligand  (HAPLOINSUFFICIENCY)
          │
          ▼
Reduced BMP receptor engagement → ↓ SMAD1/5/8 phosphorylation
     (± ↓ non-canonical MAPK/p38 — inferred)
          │
  ┌───────────────┼───────────────────────────┐
  ▼               ▼                           ▼
   GROWTH PLATE      CRANIOFACIAL                    HEART
 ↓ chondrocyte      ↓ palatogenesis /         ↓ endocardial cushion EMT
 maturation &        midface growth            ↓ OFT neural-crest septation
 hypertrophy         (Pierre-Robin)            ↓ valve/septum morphogenesis
 (EGFR, Wnt/β-cat,        │                    ↓ L-R axis cues
  IHH, IGF-I, COX-2)      │                          │
  ▼               ▼                          ▼
 Proportionate short   Cleft/high-arched    Outflow-tract CHD, BAV→aortic
 stature; brachydactyly palate; facial      aneurysm, Ebstein, VSD, TGA,
 (5th ray); 11 ribs     gestalt; micrognathia dextrocardia; WPW/arrhythmia
  └───────────────┴───────────────────────────┘
          │
          ▼
   Variable expressivity (unidentified modifiers + stochastic noise)

Dosage axis: Loss (haploinsufficiency) → SSFSC1. Gain (downstream regulatory duplication) → BDA2. BMP2 is thus a two-sided dosage-sensitive locus.

Evidence Base

PMID	Role	Contribution
29198724	Delineating cohort	Defines SSFSC1; establishes haploinsufficiency; heterozygous mouse recapitulation
37125634	Expansion + function	18 missense cases; zebrafish LOF validation; neural tube/brain/endocrine features; surveillance framework
39970956	Expansion	7 cases; language delay + secretory otitis media; global DD not core; surveillance additions
21671386	Precursor CNV	20p12.3 deletion → syndromic cleft palate via BMP2 haploinsufficiency
22965927	Precursor CNV	High penetrance, variable expressivity
33247540	Cardiac expansion	BAV + aortic aneurysm
37572998	Cardiac/laterality	Isolated dextrocardia situs solitus
15621726	Pathway	SMAD1/5/8 canonical pathway; heart/neural/cartilage roles
10362015	Mechanism (heart)	BMP2 drives cushion EMT, synergy with TGFβ3
11412030	Mechanism (heart)	BMP-2/4 required for neural-crest OFT septation
11512673	Mechanism (heart)	Bmp-2 localization in AV canal/valves
26418455	Mechanism (heart)	BMP2/SMAD/Sox9 fine-tunes cushion EMT
34773433	Mechanism (skeleton)	BMP2 required for chondrocyte maturation; EGFR cross-talk
22508079	Mechanism (skeleton)	β-catenin/BMP2 in chondrocyte maturation
17549388	Mechanism (skeleton)	BMP2 augments IGF-I mitogenic action

Limitations and Knowledge Gaps

Small evidence base: ~40+ total patients; no prevalence/incidence, survival, or formal QoL data. All frequencies are from small case series and may be biased by ascertainment.
No genotype-phenotype correlation: The basis of the wide variable expressivity (modifier genes, stochastic effects) is unknown, limiting prognostic prediction.
Mechanism partly inferred in humans: The causal chain is anchored in model-organism developmental biology (chick/mouse/zebrafish); the precise human tissue-level steps (e.g., non-canonical MAPK contribution) are inferred, not directly demonstrated in patient tissue.
No SSFSC1-specific molecular profiling: No patient transcriptomic, proteomic, metabolomic, or methylation signature exists.
No natural animal disease equivalent catalogued; no dedicated therapeutic development.

Proposed Follow-up Experiments / Actions

International registry & natural-history study to establish penetrance-by-feature frequencies, prevalence, cardiac/aortic progression rates, and QoL using standardized instruments.
Modifier-gene search via combined WGS + phenotyping across the growing cohort to explain variable expressivity.
Patient-derived iPSC models (chondrocyte and cardiac-neural-crest differentiation) to directly quantify SMAD1/5/8 dosage effects in human cells and test whether pathway-augmenting agents rescue phenotypes.
Aortic surveillance protocol for BAV-positive patients, given the demonstrated aneurysm risk, to standardize imaging intervals.
Systematic audiology/language screening implementation, per Stavrén-Eriksson recommendations, to test whether early intervention improves outcomes.
Functional assays for VUS using the validated zebrafish bmp2b ventralization readout to reclassify uncertain missense variants.

Report compiled from 10 confirmed findings and ~24 primary papers across the delineating human cohorts, developmental-biology mechanistic studies, and model-organism work. Evidence types are indicated throughout as human clinical, model organism, or in vitro.

Artifacts

Reference Validation

Checked with linkml-reference-validator 0.2.1.

Outcome	Count
References checked	20
Resolved	20
Unresolved (possible confabulation)	0
Unverifiable	0
Quoted claims checked	12
Quoted claims found in source	10
Quoted claims not found in source	2
References weighed for topical relevance	20
On topic	8
Off topic	0

Quotes not found in the cited source

Searched the abstract, any retrieved full text, and the title. A quote drawn from a part of the paper that was not retrieved will appear here too, so check before treating one as invented:

Every one of these was searched against an abstract alone, with no full text retrieved - marked abstract only below. Where full text can be fetched, re-running with it will settle them; where the source publishes only a summary to PubMed, as GeneReviews chapters do, it will not, and the quote has to be checked by hand against the chapter itself.

PMID:10362015 (abstract only): "BMP2 … plays an important role in the formation of endocardial cushion tissue and … acts synergistically with TGFbeta3 in the regulation of this developmental event"
closest text in source: "These results suggest that BMP2 1) plays an important role in the formation of endocardial cushion tissue and 2) acts synergistically with TGFbeta3 in the regulation of this developmental event."
PMID:29198724 (abstract only): "De novo occurrence and autosomal-dominant inheritance of variants, including paternal mosaicism in two affected sisters who inherited a BMP2 splice-altering variant … across all reported families"
closest text in source: "De novo occurrence and autosomal-dominant inheritance of variants, including paternal mosaicism in two affected sisters who inherited a BMP2 splice-altering variant, were observed across all reported families"

Term Validation

Checked with linkml-term-validator 0.4.5, through the ols: adapter.

Outcome	Count
Terms checked	57
Resolved	56
Unresolved (possible confabulation)	0
Obsolete	0
Unverifiable	1
Terms whose name was checked	4
Terms named correctly	1
Terms named as a different term	3

Terms the report names something else

These identifiers resolve, so nothing about them looks wrong, and the ontology calls them something unrelated to what the report calls them. That usually means the identifier is not the one the sentence needs:

MONDO:0100297 (2 mentions) - the report calls it "MONDO"; MONDO calls it short stature, facial dysmorphism, and skeletal anomalies with or without cardiac anomalies 1
NCIT:C15192 (1 mention) - the report calls it "Speech Therapy"; NCIT calls it Blood Transfusion
NCIT:C15266 (1 mention) - the report calls it "Genetic Counseling"; NCIT calls it Laparotomy

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Classifications

Inheritance

Discussions and Knowledge Gaps

Pathophysiology

Pathograph

Phenotypes

Genetic Associations

Variants

Medical Actions

Diagnosis

Prevalence

Clinical Burden

Differential Diagnoses

Experimental Models

Animal Models

Source YAML

References & Deep Research

References

Deep Research

1. Disease Information

2. Etiology

3. Phenotypes

Craniofacial (physical manifestations / clinical signs)

Growth (physical manifestation)

Skeletal (clinical signs / imaging)

Cardiac (physical manifestations / clinical signs)

Expanded spectrum (later cohorts)

4. Genetic / Molecular Information

5. Environmental Information

6. Mechanism / Pathophysiology

Causal chain (initiating lesion → clinical manifestation)

Supporting molecular detail

7. Anatomical Structures Affected

8. Temporal Development

9. Inheritance and Population

10. Diagnostics

11. Outcome / Prognosis

12. Treatment

13. Prevention

14. Other Species / Natural Disease

15. Model Organisms

Mechanistic Model / Interpretation

Evidence Base

Limitations and Knowledge Gaps

Proposed Follow-up Experiments / Actions

Artifacts

Reference Validation

Quotes not found in the cited source

Term Validation

Terms the report names something else