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Mappings

MONDO

MONDO:0007187 nevoid basal cell carcinoma syndrome

Orphanet lists MONDO:0007187 as an exact cross-reference for the ORPHA:377 Gorlin syndrome record.

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Definitions

1

Orphanet definition of Gorlin syndrome

Gorlin syndrome is a hereditary hamartosis syndrome with early-onset basal cell carcinomas, jaw keratocysts, and skeletal abnormalities.

CASE_DEFINITION Orphanet structured disease definition

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"A rare hereditary disorder due to autosomal dominant transmission with hamartosis characterized by multiple early-onset basal cell carcinoma (BCC), multiple jaw keratocysts and skeletal abnormalities."

Orphanet's definition supports the high-level hereditary syndrome framing and core clinical triad.

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Inheritance

1

Autosomal Dominant HP:0000006

Gorlin syndrome follows autosomal dominant inheritance with high penetrance but variable expressivity. Approximately 20-30% of cases arise from de novo mutations.

Autosomal dominant inheritance

Show evidence (2 references)

PMID:19032739 SUPPORT

"NBCCS is caused by mutations in the PTCH1 gene and is transmitted as an autosomal dominant trait with complete penetrance and variable expressivity."

Documents autosomal dominant inheritance with complete penetrance.

ORPHA:377 SUPPORT Other

"- Autosomal dominant"

Orphanet directly records autosomal dominant inheritance for Gorlin syndrome.

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Subtypes

2

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Mechanistic Hypotheses

3

Canonical PTCH1-Loss SMO-Dependent Hedgehog Activation

canonical_smo_dependent_model CANONICAL PTCH1-related

Evidence balance 2 support

In the predominant PTCH1-related form, germline plus somatic (Knudson two-hit) loss of PTCH1 derepresses Smoothened at the primary cilium, and constitutively active SMO drives nuclear GLI1/GLI2 activation. Because the lesion sits upstream of SMO, this model predicts sensitivity to the approved SMO antagonists vismodegib and sonidegib and is the mechanistic basis for the BCC-, jaw-cyst-, and skeletal-dominant phenotype.

Pathograph links

PTCH1 Somatic Second-Hit Loss -> SMO Constitutive Activation DIRECT Biallelic loss of PTCH1 releases SMO from tonic inhibition at the primary cilium, allowing SMO accumulation and constitutive downstream signaling

SMO Constitutive Activation -> GLI Transcription Factor Activation DIRECT Constitutively active SMO suppresses the PKA-GSK3B-BTRC phosphorylation cascade that processes GLI3 to its repressor form, and promotes SUFU release of GLI1/GLI2, driving their nuclear import and transcriptional activity

GLI Transcription Factor Activation -> Multiple Basal Cell Carcinomas INDIRECT UNKNOWN INTERMEDIATES Constitutive GLI signaling in epidermal basal cells promotes repeated BCC initiation

Show evidence (2 references)

PMID:37947611 SUPPORT Other

"Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals."

Establishes PTCH-loss-driven SMO/GLI activation as the canonical Hedgehog axis underlying BCC.

PMID:22670904 SUPPORT Human Clinical

"Vismodegib reduces the basal-cell carcinoma tumor burden and blocks growth of new basal-cell carcinomas in patients with the basal-cell nevus syndrome."

Clinical responsiveness to a SMO antagonist supports the SMO-dependent (PTCH1-upstream) canonical model.

SUFU-Loss SMO-Independent GLI Activation

sufu_smo_independent_gli_model ALTERNATIVE SUFU-related

Evidence balance 2 support

In SUFU-related disease the lesion lies downstream of SMO: loss of SUFU directly releases GLI1/GLI2 from cytoplasmic sequestration, activating the pathway independently of SMO. This model explains the distinct SUFU phenotype (markedly higher early-childhood SHH medulloblastoma, meningioma, and gonadal-tumor risk with fewer jaw cysts) and predicts that SMO antagonists acting upstream of the SUFU/GLI node will be of limited benefit in SUFU carriers.

Pathograph links

SUFU Germline Mutations -> GLI Transcription Factor Activation DIRECT Loss of SUFU-mediated GLI sequestration directly releases GLI1 and GLI2 to the nucleus, bypassing SMO-level regulation and making the pathway insensitive to SMO inhibitors such as vismodegib and sonidegib

GLI Transcription Factor Activation -> SHH-Responsive Cerebellar Progenitor Expansion INDIRECT UNKNOWN INTERMEDIATES Excess pathway output sustains proliferation in cerebellar precursors

Show evidence (2 references)

PMID:25403219 SUPPORT Human Clinical

"We found a < 2% risk in PTCH1 mutation-positive individuals, with a risk up to 20× higher in SUFU mutation-positive individuals."

Genotype-specific medulloblastoma risk supports a mechanistically distinct SUFU branch acting downstream of SMO.

PMID:28596197 SUPPORT Human Clinical

"Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."

Distinct SUFU tumor spectrum supports an SMO-independent GLI-activation model separate from the canonical PTCH1 axis.

SMO-Inhibitor Resistance via Downstream GLI Bypass

gli_bypass_resistance_model EMERGING

Evidence balance 6 support

SMO antagonists eventually fail in a substantial fraction of advanced BCCs. Resistance arises from acquired SMO mutations, SUFU loss, GLI2 amplification, and non-canonical GLI activation that all converge below the drug target, leaving constitutive GLI output intact. This model frames the convergent GLI node — not SMO — as the durable therapeutic bottleneck and motivates GLI-directed agents for SMO-inhibitor-resistant and SUFU-driven disease.

OpenScientist deep research (kb/hypotheses/Gorlin_Syndrome/gli_bypass_resistance_model) judged this hypothesis PARTIALLY SUPPORTED: GLI-convergent bypass is a real, well-documented resistance route (acquired SMO mutations account for ~50% of resistant sporadic BCC; aPKC-ι/λ non-canonical GLI activation; GLI2 amplification; and inherent SUFU-driven activation below SMO), and GLI-node targeting (BET/HDAC/aPKC inhibitors) overcomes resistance preclinically. Qualifications: (1) the model is strongest for SUFU-driven disease (BCNS2/MHIBCC) and sporadic advanced BCC, but weak for PTCH1-mutant Gorlin syndrome, where BCCs are uniformly suppressed by SMO inhibitors and secondary resistance is rare (~9% vs ~77% in sporadic advanced BCC). (2) In the one molecularly studied resistant Gorlin tumor, resistance arose via a GLI-independent basal-to-squamous lineage transition, not GLI bypass. (3) Additional GLI-independent routes exist (primary-cilia-loss RAS/MAPK switching; WNT-dependent persister cells). (4) The therapeutic corollary is clinically unproven — the only GLI-directed trial (arsenic trioxide + itraconazole, n=5) achieved ~75% GLI1 suppression but no meaningful tumor responses. Status EMERGING is retained pending Gorlin-specific, multi-patient resistance genomics.

Pathograph links

GLI Transcription Factor Activation -> Multiple Basal Cell Carcinomas INDIRECT UNKNOWN INTERMEDIATES Constitutive GLI signaling in epidermal basal cells promotes repeated BCC initiation

Deep research

OpenScientist citations 24 citations 2026-07-06T13:02:12.185183

Show evidence (6 references)

PMID:31036756 SUPPORT Other

"Resistance to SMO inhibitors is caused by acquired SMO mutations, SUFU deletions, GLI2 amplification, other by-passing mechanisms of GLI activation and WNT/β-catenin signaling activation."

Documents the downstream-of-SMO bypass mechanisms that sustain GLI output despite SMO blockade.

PMID:25759020 SUPPORT Human Clinical

"Here we identify SMO mutations in 50% (22 of 44) of resistant BCCs and show that these mutations maintain Hedgehog signaling in the presence of SMO inhibitors"

Sequencing of 44 resistant BCCs shows acquired SMO mutations sustain constitutive Hedgehog/GLI output despite SMO inhibition, the strongest quantitative support for GLI-convergent resistance.

PMID:23446420 SUPPORT In Vitro

"aPKC-ι/λ functions downstream of SMO to phosphorylate and activate GLI1, resulting in maximal DNA binding and transcriptional activation. Activated aPKC-ι/λ is upregulated in SMO-inhibitor-resistant tumours and targeting aPKC-ι/λ suppresses signalling and growth of resistant BCC cell lines."

Identifies aPKC-ι/λ as a non-canonical GLI activator acting below SMO that is upregulated in resistant tumors, a direct GLI-bypass route validated in resistant BCC cell lines.

+ 3 more references

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Discussions and Knowledge Gaps

3

Can GLI-directed agents control SMO-inhibitor-resistant or SUFU-driven Gorlin tumors, given that the durable therapeutic bottleneck lies at the convergent GLI node rather than at SMO?

KNOWLEDGE GAP OPEN gap_gli_directed_therapy_resistance

Attached to

pathophysiology#GLI Transcription Factor Activation pathophysiology#SMO Constitutive Activation

The only approved targeted therapies for Gorlin-associated BCC (vismodegib, sonidegib) act at SMO and therefore have limited efficacy in SUFU-related disease, which activates GLI downstream of SMO, and in tumors that acquire resistance via SMO mutation, SUFU loss, or GLI2 amplification. No GLI-directed drug is approved, leaving SUFU carriers and SMO-inhibitor-resistant patients without a pathway-targeted option. Resolving whether GLI antagonists are effective and tolerable would close a major translational gap shared by the sufu_smo_independent_gli_model and gli_bypass_resistance_model hypotheses.

Proposed experiments

GLI-directed therapy in SUFU-null and SMO-inhibitor-resistant Gorlin models

controlled perturbation experiment

exp_gli_antagonist_sufu_resistant_models

Test GLI-DNA-interaction inhibitors and GLI2 destabilizers against patient-derived SUFU-mutant medulloblastoma neural stem cells, PTCH1-mutant BCC organoids, and isogenic vismodegib-resistant BCC lines bearing SMO mutations or GLI2 amplification, comparing GLI output, proliferation, and tumor growth with SMO-antagonist arms.

Decision criterion

GLI-directed agents reduce GLI target-gene expression and tumor growth in SUFU-null and SMO-inhibitor-resistant models where SMO antagonists fail.

Would support

mechanistic_hypotheses#gli_bypass_resistance_model mechanistic_hypotheses#sufu_smo_independent_gli_model

Would refute

mechanistic_hypotheses#canonical_smo_dependent_model

Show evidence (1 reference)

PMID:31036756 SUPPORT Other

"GLI-DNA-interaction inhibitors (glabrescione B and GANT61), GLI2 destabilizers (arsenic trioxide and pirfenidone) and a GLI-deacetylation inhibitor (4SC-202) were shown to block GLI-dependent transcription and tumorigenesis in preclinical studies."

Preclinical GLI-directed agents exist but none are clinically validated for Gorlin disease, defining the translational gap.

Why does PTCH1 loss preferentially drive BCC, jaw cysts, and skeletal anomalies while SUFU loss preferentially drives early-childhood medulloblastoma, meningioma, and gonadal tumors, despite both converging on GLI activation?

KNOWLEDGE GAP OPEN gap_genotype_tissue_specificity

Attached to

pathophysiology#SUFU Germline Mutations pathophysiology#SHH-Responsive Cerebellar Progenitor Expansion pathophysiology#GLI Transcription Factor Activation

The strong, reproducible genotype-phenotype divergence between PTCH1 and SUFU carriers implies that the two lesions are not simply interchangeable inputs to a single GLI output. Tissue-specific differences in ciliary signaling, SUFU's GLI-stabilizing versus GLI-repressing roles, dosage thresholds, and the timing of second-hit inactivation in cerebellar granule precursors versus epidermal basal cells are all candidate explanations, but the mechanistic basis is unresolved. Closing this gap would refine surveillance (which tissues to watch by genotype) and clarify why SMO-level versus GLI-level lesions yield distinct tumor spectra.

Proposed experiments

Lineage-resolved Hedgehog output in isogenic PTCH1-null versus SUFU-null cells

comparative isogenic differentiation assay

exp_genotype_lineage_resolved_hh_output

Generate isogenic PTCH1-null and SUFU-null human iPSC lines, differentiate into cerebellar granule-cell precursors, epidermal basal keratinocytes, and meningeal/gonadal-relevant lineages, and quantify ciliary GLI processing, GLI activator/repressor balance, and proliferative response per lineage.

Decision criterion

SUFU-null cells show disproportionately higher GLI-activator output in cerebellar precursors than PTCH1-null cells, while PTCH1-null cells show stronger output in basal keratinocytes.

Would support

mechanistic_hypotheses#sufu_smo_independent_gli_model

Is there a durable, low-toxicity field therapy that prevents new BCC formation in Gorlin syndrome without the systemic adverse effects and rebound regrowth that limit oral Hedgehog inhibitors?

KNOWLEDGE GAP OPEN gap_durable_low_toxicity_chemoprevention

Attached to

pathophysiology#SMO Constitutive Activation phenotypes#Multiple Basal Cell Carcinomas

Patients accumulate hundreds of lifelong BCCs, yet oral SMO antagonists cause muscle spasms, dysgeusia, and alopecia that drive discontinuation in over half of patients, and tumors regrow after stopping. Topical patidegib is a promising field approach but remains investigational on small phase II data, and recent consensus guidelines note that Gorlin-specific evidence is sparse. Whether a chronically tolerable preventive therapy exists is an open clinical gap.

Proposed experiments

Adequately powered trial of topical Hedgehog-inhibitor field chemoprevention

randomized controlled trial

exp_topical_hhi_chemoprevention_rct

Conduct a larger randomized controlled trial of topical patidegib (or a next-generation topical SMO/GLI inhibitor) versus vehicle in Gorlin syndrome, with new-BCC incidence, systemic drug exposure, and quality-of-life endpoints over multi-year follow-up.

Decision criterion

Topical therapy significantly reduces new-BCC incidence versus vehicle with low systemic exposure and acceptable tolerability sustained over years.

Show evidence (2 references)

PMID:39545486 SUPPORT Human Clinical

"Patidegib topical gel warrants further clinical development."

The trial authors themselves flag that topical Hedgehog-inhibitor chemoprevention is promising but not yet established, defining the gap.

PMID:41396574 SUPPORT Other

"Given the scarcity of GS-specific data, expert consensus informed several recommendations, highlighting the need for ongoing research to strengthen the evidence base."

2025 consensus guidelines explicitly identify the sparse Gorlin-specific evidence base as an unmet research need.

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Pathophysiology

15

PTCH1 Germline First-Hit Loss-of-Function

PTCH1 encodes Patched 1, a 12-pass transmembrane receptor that normally suppresses Smoothened (SMO) in the absence of Hedgehog ligand. Germline heterozygous loss-of-function mutations in PTCH1 predispose to tumors following Knudson's two-hit model. Loss of the remaining wild-type allele in somatic cells leads to constitutive Hedgehog pathway activation and tumor development.

PTCH1 hgnc:9585

Genetic context PTCH1 hgnc:9585 functional_impact_category: LOSS_OF_FUNCTION

Germline plus somatic (Knudson two-hit) loss-of-function of the tumor-suppressor negative regulator PTCH1; gene-level loss produces net Hedgehog pathway activation.

Downstream

PTCH1 Somatic Second-Hit Loss The constitutional heterozygous PTCH1 lesion is the first of the two hits required for tumor-cell Hedgehog derepression; a somatic loss of the remaining wild-type allele in a susceptible cell completes biallelic inactivation.

Show evidence (3 references)

PMID:19032739 SUPPORT

"NBCCS is caused by mutations in the PTCH1 gene and is transmitted as an autosomal dominant trait with complete penetrance and variable expressivity."

Establishes PTCH1 as the causative gene for NBCCS with autosomal dominant inheritance.

PMID:28596197 SUPPORT

"Heterozygous germline variants in PTCH1 and SUFU encoding components of the Sonic hedgehog pathway explain the majority of cases."

Confirms PTCH1 germline variants as the primary genetic cause of Gorlin syndrome.

CGDS:HGNC_9585 SUPPORT Other

"Loss of function variants within this gene have been associated with nevoid basal cell carcinoma syndrome."

ClinGen dosage sensitivity supports PTCH1 haploinsufficiency/loss-of-function as a mechanism for nevoid basal cell carcinoma syndrome.

PTCH1 Somatic Second-Hit Loss

Somatic loss of the remaining wild-type PTCH1 allele in a susceptible cell — the Knudson second hit that completes biallelic PTCH1 inactivation. Loss of heterozygosity at 9q22 is the classic mechanism in Gorlin BCCs. Once both alleles are inactivated, Smoothened is released from tonic Patched inhibition and accumulates constitutively at the primary cilium.

Canonical PTCH1-Loss SMO-Dependent Hedgehog Activation

basal cell of epidermis CL:0002187

PTCH1 hgnc:9585

Downstream

SMO Constitutive Activation Biallelic loss of PTCH1 releases SMO from tonic inhibition at the primary cilium, allowing SMO accumulation and constitutive downstream signaling

Show evidence (1 reference)

PMID:8681379 SUPPORT

"Familial and sporadic BCCs display loss of heterozygosity in this region, consistent with the gene being a tumor suppressor."

Direct LOH evidence for biallelic PTCH1 inactivation (Knudson second hit) in Gorlin-associated BCCs.

SUFU Germline Mutations

A minority of Gorlin syndrome cases (approximately 5%) are caused by germline mutations in SUFU (Suppressor of Fused), which encodes a negative regulator of GLI transcription factors. SUFU mutations are associated with markedly higher risk of medulloblastoma (up to 20-fold higher) compared to PTCH1 mutations, with tumors typically occurring before age 3 years.

SUFU-Loss SMO-Independent GLI Activation

SUFU hgnc:16466

Genetic context SUFU hgnc:16466 functional_impact_category: LOSS_OF_FUNCTION

Loss-of-function of the negative regulator SUFU; because SUFU acts downstream of SMO, the gene-level loss activates GLI output independently of Smoothened (the SMO-inhibitor-resistant branch).

negative regulation of smoothened signaling pathway GO:0045879 ↓ DECREASED

Downstream

GLI Transcription Factor Activation Loss of SUFU-mediated GLI sequestration directly releases GLI1 and GLI2 to the nucleus, bypassing SMO-level regulation and making the pathway insensitive to SMO inhibitors such as vismodegib and sonidegib

SUFU-Associated Meningioma Predisposition SUFU germline LOF predisposes to meningioma

SUFU-Associated Ovarian Fibroma Predisposition SUFU germline LOF predisposes to ovarian fibroma

SUFU-Associated Gonadal Tumor Predisposition SUFU germline LOF predisposes to gonadal tumors

Show evidence (2 references)

PMID:25403219 SUPPORT

"We found a < 2% risk in PTCH1 mutation-positive individuals, with a risk up to 20× higher in SUFU mutation-positive individuals."

Demonstrates that SUFU mutations confer dramatically higher medulloblastoma risk than PTCH1 mutations.

PMID:29186568 SUPPORT

"Germline SUFU mutations strongly predispose to medulloblastoma in the first years of life, with worse prognosis than usually observed for SHH medulloblastoma."

Confirms high medulloblastoma risk and poor prognosis in SUFU mutation carriers.

SMO Constitutive Activation

PTCH1 normally suppresses Smoothened (SMO) by preventing its accumulation in the primary ciliary membrane. When PTCH1 is lost via Knudson second-hit inactivation, SMO is no longer restrained and accumulates constitutively at the cilium, triggering downstream GLI signaling. This SMO-active state is the direct molecular target of the approved Hedgehog-pathway inhibitors vismodegib and sonidegib: both drugs bind SMO and restore its inhibited conformation. SUFU-mutant Gorlin disease bypasses this node entirely, predicting reduced efficacy of SMO inhibitors for that genotype.

Canonical PTCH1-Loss SMO-Dependent Hedgehog Activation

basal cell of epidermis CL:0002187

smoothened signaling pathway GO:0007224 ↑ INCREASED

Downstream

GLI Transcription Factor Activation Constitutively active SMO suppresses the PKA-GSK3B-BTRC phosphorylation cascade that processes GLI3 to its repressor form, and promotes SUFU release of GLI1/GLI2, driving their nuclear import and transcriptional activity

Show evidence (2 references)

PMID:37947611 SUPPORT

"Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals."

Establishes PTCH and SMO as the upstream pathway lesions driving GLI activation in BCC; supports the mechanistic model that PTCH1 loss derepresses SMO constitutive activity.

PMID:22670904 SUPPORT

"Dysregulated hedgehog signaling is the pivotal molecular abnormality underlying basal-cell carcinomas. Vismodegib is a new orally administered hedgehog-pathway inhibitor that produces objective responses in locally advanced and metastatic basal-cell carcinomas."

Confirms that vismodegib targets dysregulated Hedgehog signaling (acting at SMO) and is efficacious in Gorlin syndrome BCCs; supports this node as the druggable point of intervention.

GLI Transcription Factor Activation

Both PTCH1 loss (via SMO derepression) and SUFU loss (via direct release of GLI sequestration) converge on constitutive nuclear accumulation of GLI1 and GLI2. GLI1 transcriptionally activates pro-proliferative targets including CCND1, BCL2, and MYCN, and drives a positive-feedback loop by inducing PTCH1 expression. Loss of the GLI3 repressor arm (GLI3R, which requires PKA-GSK3B-BTRC-mediated partial proteolysis) compounds the transcriptional imbalance. This convergent GLI activation node links both genotypic etiologies to the full spectrum of Gorlin developmental and neoplastic phenotypes. Resistance to SMO inhibitors can emerge through amplification or activation of GLI downstream of SMO, a mechanism invisible in schema representations that bundle SMO and GLI as a single pathway node.

Canonical PTCH1-Loss SMO-Dependent Hedgehog Activation SMO-Inhibitor Resistance via Downstream GLI Bypass SUFU-Loss SMO-Independent GLI Activation

basal cell of epidermis CL:0002187

smoothened signaling pathway GO:0007224 ↑ INCREASED cell population proliferation GO:0008283 ↑ INCREASED

Downstream

Multiple Basal Cell Carcinomas Constitutive GLI signaling in epidermal basal cells promotes repeated BCC initiation

Palmoplantar Keratinization Abnormalities Aberrant pathway output disrupts palmoplantar keratinocyte differentiation and surface integrity

Odontogenic Keratocysts Hedgehog dysregulation alters odontogenic epithelial growth and jaw cyst formation

SHH-Responsive Cerebellar Progenitor Expansion Excess pathway output sustains proliferation in cerebellar precursors

Hedgehog-Driven Osteogenic Dysregulation Developmental Hedgehog hyperactivity perturbs craniofacial and skeletal patterning

Hedgehog-Driven Craniofacial Patterning Dysregulation Developmental Hedgehog dysregulation perturbs neural-crest-driven growth and patterning of the face and skull base

Hedgehog-Dependent Ocular Developmental Dysregulation Dysregulated Hedgehog output alters optic vesicle patterning and lens differentiation during eye development

Hedgehog-Dependent Secondary Palate Development Disruption Abnormal Hedgehog signaling perturbs palatal morphogenesis and increases cleft risk

Hedgehog-Driven Mesenchymal Tumor Predisposition Constitutive pathway activation broadens susceptibility to benign mesenchymal tumors such as fibromas

Show evidence (1 reference)

PMID:37947611 SUPPORT

"Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals."

Confirms that PTCH, SUFU, and SMO mutations all converge on aberrant GLI transcription factor activation, establishing the GLI node as the functional convergence point of multiple upstream etiologies.

Palmoplantar Keratinization Abnormalities

Palmoplantar skin in Gorlin syndrome shows abnormal keratinization and surface differentiation, consistent with the characteristic palmar and plantar pits.

keratinocyte CL:0000312

keratinization GO:0031424 ⚠ ABNORMAL

Downstream

Palmar Pits Focal palmoplantar epithelial defects manifest clinically as palmar pits

Plantar Pits Similar keratinization defects on the soles produce plantar pits

Show evidence (2 references)

PMID:19032739 SUPPORT Human Clinical

"Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles"

Reviews palmoplantar keratinization abnormalities as a core manifestation of Gorlin syndrome.

PMID:9096761 SUPPORT Human Clinical

"Palmar pits and plantar pits were seen in 87%."

Large NIH cohort confirms that pits are a common clinical expression of the palmoplantar epithelial abnormality.

SHH-Responsive Cerebellar Progenitor Expansion

Sonic Hedgehog normally drives proliferation of cerebellar granule cell precursors during development. In Gorlin syndrome, constitutive pathway activation in this lineage creates a substrate for early-childhood SHH medulloblastoma, particularly in SUFU-related disease.

cerebellar granule cell CL:0001031

cell population proliferation GO:0008283 ↑ INCREASED cerebellum development GO:0021549 ⚠ ABNORMAL

Downstream

Medulloblastoma Persistent SHH dependence in cerebellar precursor populations drives infant medulloblastoma risk

Show evidence (2 references)

PMID:10027293 SUPPORT Model Organism

"Sonic hedgehog (Shh), which is made by Purkinje cells, regulates the division of granule cell precursors (GCPs)."

Foundational cerebellar developmental evidence that SHH controls granule cell precursor proliferation, the lineage exploited in Gorlin-associated medulloblastoma.

PMID:32747535 SUPPORT Model Organism

"We found that Gorlin NES cells formed tumors in mouse cerebellum mimicking human medulloblastoma."

Disease-specific patient iPSC model shows that Gorlin neural stem cells can generate medulloblastoma-like tumors in the cerebellar environment.

Hedgehog-Driven Osteogenic Dysregulation

Constitutive Hedgehog signaling also perturbs osteoblast differentiation and skeletal patterning. Patient-derived PTCH1-mutant iPSCs show constitutive Hh activity and hypersensitivity to osteogenic induction, providing a mechanistic link to macrocephaly, rib and vertebral anomalies, pectus deformity, Sprengel anomaly, and falx calcification.

osteoblast CL:0000062

osteoblast differentiation GO:0001649 ⚠ ABNORMAL

Downstream

Macrocephaly Altered craniofacial growth contributes to enlarged head circumference

Rib Anomalies Abnormal axial skeletal patterning can produce bifid, splayed, or fused ribs

Vertebral Anomalies Abnormal vertebral development leads to segmentation and shape defects

Pectus Deformity Chest wall development is perturbed as part of the skeletal phenotype

Sprengel Anomaly Shoulder girdle patterning defects contribute to elevated scapula morphology

Calcification of Falx Cerebri Ectopic intracranial calcification reflects abnormal ossification and calcification responses

Show evidence (1 reference)

PMID:29088246 SUPPORT In Vitro

"We propose that Hh signaling is constituently active in iPSCs from Gorlin syndrome patients, enhancing their response to osteogenic induction and contributing to disease-associated abnormalities."

Patient-derived PTCH1-mutant iPSC data support constitutive Hedgehog activity causing abnormal osteogenic responses relevant to the Gorlin skeletal phenotype.

Hedgehog-Driven Craniofacial Patterning Dysregulation

Hedgehog pathway dysregulation in cranial neural crest-derived tissues perturbs the patterning and growth of facial primordia and skull-base structures, providing a developmental basis for the characteristic craniofacial gestalt.

neural crest cell CL:0011012

neural crest cell migration GO:0001755 ⚠ ABNORMAL mesenchymal cell proliferation GO:0010463 ⚠ ABNORMAL

Downstream

Macrocephaly Altered craniofacial growth contributes to enlarged head circumference

Hypertelorism Abnormal facial primordia patterning widens the orbital spacing

Frontal Bossing Dysregulated skull and forehead growth contributes to frontal prominence

Coarse Facial Features Cumulative craniofacial patterning defects produce the recognizable coarse facies

Bridged Sella Turcica Skull-base patterning abnormalities contribute to sellar bridging on imaging

Show evidence (2 references)

PMID:15107405 SUPPORT Model Organism

"Together, our results demonstrate that Hh signaling in NCCs is essential for normal patterning and growth of the face."

Neural crest-restricted model establishes Hedgehog signaling as a core determinant of facial growth and patterning.

PMID:37481904 SUPPORT Other

"Studies in animal models have revealed that SHH signaling plays crucial roles at multiple stages of craniofacial morphogenesis, from cranial neural crest cell survival to growth and patterning of the facial primordia"

Recent review summarizes the broad dependence of craniofacial morphogenesis on Hedgehog signaling.

Hedgehog-Dependent Ocular Developmental Dysregulation

Dysregulated Hedgehog pathway activity perturbs optic vesicle patterning and lens differentiation during development, providing a mechanistic bridge to the ocular phenotype in Gorlin syndrome.

eye development GO:0001654 ⚠ ABNORMAL camera-type eye development GO:0043010 ⚠ ABNORMAL lens fiber cell differentiation GO:0070306 ⚠ ABNORMAL

eye UBERON:0000970

Downstream

Strabismus Developmental ocular abnormalities can manifest as abnormal ocular alignment

Congenital Cataracts Lens differentiation defects increase cataract susceptibility

Nystagmus Early visual-system developmental abnormalities can contribute to nystagmus

Coloboma Disrupted optic vesicle and fissure patterning predispose to coloboma

Show evidence (2 references)

PMID:18479681 SUPPORT Model Organism

"These observations highlight the critical role that Hedgehog pathway activity plays in mediating patterning of the proximal/distal axis of the optic vesicle during the early phases of eye development"

Patched1-dependent model directly links Hedgehog pathway dysregulation to early vertebrate eye patterning defects.

PMID:22491411 SUPPORT Model Organism

"Hedgehog signaling is implicated in eye development, and defects in hedgehog signaling components have been shown to result in defects of the retina, iris, and lens."

Lens-development model supports a broad role for Hedgehog dysregulation across multiple ocular structures.

Hedgehog-Dependent Secondary Palate Development Disruption

Hedgehog signaling interacts with other developmental pathways during palatal morphogenesis, and dysregulation of this program provides a mechanistic basis for cleft palate in Gorlin syndrome.

Downstream

Cleft Palate Disturbed palatal development increases the risk of clefting

Show evidence (1 reference)

PMID:31072004 SUPPORT Model Organism

"Using genetic and experimental approaches in the mouse, we show that during development of ontogenetically different organs, including the tail, genital tubercle, and secondary palate, Sonic hedgehog (SHH) loss-of-function causes anomalies"

Mouse developmental data directly implicate SHH signaling in normal secondary palate morphogenesis.

Hedgehog-Driven Mesenchymal Tumor Predisposition

Gorlin syndrome includes a broader benign mesenchymal tumor predisposition, particularly fibromas in the heart and ovary, consistent with constitutive Hedgehog-pathway-driven proliferative susceptibility across multiple tissues.

mesenchymal cell CL:0008019

cell population proliferation GO:0008283 ↑ INCREASED

Downstream

Cardiac Fibroma Benign mesenchymal tumor susceptibility can manifest as cardiac fibroma

Ovarian Fibroma The same fibroma predisposition contributes to ovarian fibroma risk

Show evidence (2 references)

PMID:33860896 SUPPORT Other

"Gorlin syndrome (MIM 109,400), a cancer predisposition syndrome related to a constitutional pathogenic variation (PV) of a gene in the Sonic Hedgehog pathway (PTCH1 or SUFU), is associated with a broad spectrum of benign and malignant tumors."

Surveillance review supports a dedicated non-cutaneous tumor-predisposition branch within Gorlin syndrome.

PMID:33860896 SUPPORT Other

"Basal cell carcinomas (BCC), odontogenic keratocysts and medulloblastomas are the main tumor types encountered, but meningiomas, ovarian or cardiac fibromas and sarcomas have also been described."

Same review explicitly places ovarian and cardiac fibromas within the Gorlin tumor spectrum.

SUFU-Associated Meningioma Predisposition

SUFU germline loss-of-function genetically predisposes to meningioma (meningeal tissue), part of the extra-cutaneous tumor spectrum that distinguishes SUFU carriers from PTCH1 carriers.

Downstream

Meningioma SUFU germline LOF drives meningeal tumor development

Show evidence (2 references)

PMID:28596197 SUPPORT Human Clinical

"Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."

Genotype-phenotype study shows meningioma is significantly enriched in SUFU-mutant Gorlin carriers.

PMID:35768194 SUPPORT Human Clinical

"Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients)."

Large collaborative cohort documents 20/172 SUFU carriers with meningioma.

SUFU-Associated Ovarian Fibroma Predisposition

SUFU germline loss-of-function genetically predisposes to ovarian fibroma (ovarian stromal tissue), significantly enriched in SUFU carriers relative to PTCH1 carriers.

Downstream

Ovarian Fibroma SUFU germline LOF drives ovarian stromal fibroma development

Show evidence (1 reference)

PMID:28596197 SUPPORT Human Clinical

"Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."

Ovarian fibroma is significantly enriched in SUFU-mutant Gorlin carriers.

SUFU-Associated Gonadal Tumor Predisposition

SUFU germline loss-of-function genetically predisposes to adolescent and adult gonadal tumors (gonadal tissue), a component of the SUFU extra-cutaneous tumor spectrum distinct from ovarian fibroma.

Downstream

Gonadal Tumors SUFU germline LOF drives adolescent gonadal tumor development

Show evidence (1 reference)

PMID:35768194 SUPPORT Human Clinical

"Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients)."

Large cohort documents 11/172 SUFU carriers with gonadal tumors distinct from ovarian fibroma.

⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.

●

Phenotypes

29

Cardiovascular 1

Cardiac Fibroma VERY_RARE HP:0010617

Show evidence (1 reference)

PMID:8326488 SUPPORT Human Clinical

"Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."

Population-based study documents cardiac fibroma as a recognized but uncommon Gorlin syndrome complication.

Digestive 1

Odontogenic Keratocysts VERY_FREQUENT Odontogenic keratocysts of the jaw HP:0010603

Show evidence (1 reference)

PMID:19032739 SUPPORT

"Recurrent jaw cysts occur in 90% of patients."

Documents high frequency of odontogenic keratocysts in Gorlin syndrome.

Eye 6

Strabismus FREQUENT HP:0000486

Show evidence (1 reference)

PMID:31533758 SUPPORT Human Clinical

"highlights strabismus (63% of the patients), epiretinal membranes (36%) and myelinated optic nerve fiber layers (36%) as the most frequent ophthalmological findings in this group of patients."

Dedicated ophthalmologic study documenting strabismus in 63% of Gorlin-Goltz syndrome patients as the most frequent ocular finding.

Congenital Cataracts OCCASIONAL Developmental cataract HP:0000519

Show evidence (2 references)

PMID:31533758 SUPPORT Human Clinical

"Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"

Systematic ophthalmologic evaluation documenting congenital cataract in 18% of Gorlin-Goltz syndrome patients.

PMID:8326488 SUPPORT Human Clinical

"Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."

Population-based study documenting combined ophthalmic abnormalities (squint or cataract) in 26% of NBCCS patients; not cataract-specific.

Nystagmus OCCASIONAL HP:0000639

Show evidence (1 reference)

PMID:31533758 SUPPORT Human Clinical

"Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"

Dedicated ophthalmologic evaluation documents nystagmus in 9% of Gorlin-Goltz syndrome patients.

Coloboma OCCASIONAL HP:0000589

Show evidence (1 reference)

PMID:31533758 SUPPORT Human Clinical

"Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"

Dedicated ophthalmologic evaluation documents colobomas in 9% of Gorlin-Goltz syndrome patients.

Glaucoma OCCASIONAL HP:0000501

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"HP:0000501 | Glaucoma | Occasional (29-5%)"

Orphanet's HPO annotation independently classifies glaucoma as occasional in Gorlin syndrome.

Hypertelorism FREQUENT HP:0000316

Show evidence (2 references)

PMID:9096761 SUPPORT Human Clinical

"hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."

Large NIH cohort study documenting hypertelorism in 42% of 105 NBCCS patients.

PMID:31533758 SUPPORT Human Clinical

"Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"

Confirms hypertelorism in 45.5% of Gorlin-Goltz syndrome patients in a dedicated ophthalmologic evaluation.

Genitourinary 1

Ovarian Fibroma OCCASIONAL HP:0010618

Show evidence (4 references)

PMID:8326488 SUPPORT Human Clinical

"Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."

Population-based study of 84 NBCCS cases documenting ovarian calcification or fibroma in 24% of females.

PMID:9096761 SUPPORT Human Clinical

"Ovarian fibromas were diagnosed by ultrasound in 9/52 (17%) at a mean age of 30 years."

Large NIH cohort study documenting ovarian fibroma frequency in 17% of NBCCS females.

PMID:28596197 SUPPORT Human Clinical

"Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."

Documents significant enrichment of ovarian fibroma in SUFU versus PTCH1 mutation carriers.

+ 1 more reference

Head and Neck 4

Macrocephaly FREQUENT HP:0000256

Show evidence (2 references)

PMID:22918513 SUPPORT Human Clinical

"Macrocephaly was seen in 50% of affected and 8% of unaffected children/teenagers."

Pediatric Gorlin cohort documents macrocephaly as a common early feature.

ORPHA:377 SUPPORT Other

"HP:0000256 | Macrocephaly | Frequent (79-30%)"

Orphanet's HPO annotation independently classifies macrocephaly as frequent in Gorlin syndrome.

Frontal Bossing OCCASIONAL HP:0002007

Show evidence (2 references)

PMID:9096761 SUPPORT Human Clinical

"hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."

Large NIH cohort documenting frontal bossing in 27% of 105 NBCCS patients.

ORPHA:377 SUPPORT Other

"HP:0002007 | Frontal bossing | Occasional (29-5%)"

Orphanet's HPO annotation independently classifies frontal bossing as occasional in Gorlin syndrome.

Coarse Facial Features FREQUENT HP:0000280

Show evidence (1 reference)

PMID:9096761 SUPPORT Human Clinical

""coarse face" in 54%, relative macrocephaly in 50%, hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."

Large NIH cohort documents coarse facial features in 54% of affected individuals.

Cleft Palate OCCASIONAL HP:0000175

Show evidence (1 reference)

PMID:8326488 SUPPORT Human Clinical

"Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."

Population-based study documents cleft palate in 5% of NBCCS cases.

Integument 4

Multiple Basal Cell Carcinomas VERY_FREQUENT HP:0002671

Show evidence (2 references)

PMID:19032739 SUPPORT

"BCCs (varying clinically from flesh-colored papules to ulcerating plaques and in diameter from 1 to 10 mm) are most commonly located on the face, back and chest. The number of BBCs varies from a few to several thousand."

Documents variable presentation and multiplicity of BCCs in Gorlin syndrome.

PMID:40105068 SUPPORT Human Clinical

"The majority of basal cell carcinomas were located in the head and neck region (80.7%), with nodular BCC being the most common tumour type (47.0%)."

Recent comparative clinicopathology study characterizes the anatomic distribution and histologic subtype profile of syndromic BCCs, showing a head-and-neck anatomic predominance (80.7%) and predominantly nodular histology (47.0%).

Palmar Pits VERY_FREQUENT HP:0010610

Show evidence (2 references)

PMID:19032739 SUPPORT

"Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles"

Documents palmar manifestations as a main clinical feature of Gorlin syndrome.

ORPHA:377 SUPPORT Other

"HP:0010610 | Palmar pits | Very frequent (99-80%)"

Orphanet's HPO annotation independently classifies palmar pits as very frequent in Gorlin syndrome.

Plantar Pits VERY_FREQUENT HP:0010612

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"HP:0010612 | Plantar pits | Very frequent (99-80%)"

Orphanet's HPO annotation independently classifies plantar pits as very frequent in Gorlin syndrome.

Facial Milia HP:0001056

Show evidence (1 reference)

PMID:20301330 SUPPORT Other

"Many individuals have a recognizable appearance with macrocephaly, frontal bossing, coarse facial features, and facial milia."

GeneReviews explicitly includes facial milia among the recognizable clinical features of Gorlin syndrome.

Limbs 1

Brachydactyly FREQUENT HP:0001156

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"HP:0001156 | Brachydactyly | Frequent (79-30%)"

Orphanet's HPO annotation independently classifies brachydactyly as frequent in Gorlin syndrome.

Musculoskeletal 4

Rib Anomalies FREQUENT Abnormal rib morphology HP:0000772

Show evidence (3 references)

PMID:22918513 SUPPORT Human Clinical

"PURPOSE: Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, jaw cysts, palmar/plantar pits, spine and rib anomalies, and falx cerebri calcification."

Pediatric cohort abstract explicitly lists rib anomalies as part of the Gorlin skeletal phenotype.

PMID:9096761 SUPPORT Human Clinical

"bifid ribs in 26%, hemivertebrae in 15%, fusion of the vertebral bodies in 10%"

Large NIH cohort quantifies bifid ribs in 26% of affected individuals, supporting the frequent rib-anomaly designation.

ORPHA:377 SUPPORT Other

"HP:0000772 | Abnormal rib morphology | Frequent (79-30%)"

Orphanet's HPO annotation independently classifies abnormal rib morphology as frequent in Gorlin syndrome.

Vertebral Anomalies OCCASIONAL Abnormal vertebral morphology HP:0003468

Show evidence (1 reference)

PMID:22918513 SUPPORT Human Clinical

"PURPOSE: Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, jaw cysts, palmar/plantar pits, spine and rib anomalies, and falx cerebri calcification."

Pediatric cohort abstract explicitly lists spine anomalies as part of the Gorlin skeletal phenotype.

Scoliosis FREQUENT HP:0002650

Show evidence (2 references)

PMID:22918513 SUPPORT Human Clinical

"PURPOSE: Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, jaw cysts, palmar/plantar pits, spine and rib anomalies, and falx cerebri calcification."

Pediatric cohort abstract lists spine anomalies, the category that encompasses scoliosis, as part of the Gorlin skeletal phenotype.

ORPHA:377 SUPPORT Other

"HP:0002650 | Scoliosis | Frequent (79-30%)"

Orphanet's HPO annotation independently classifies scoliosis as frequent in Gorlin syndrome.

Calcification of Falx Cerebri FREQUENT HP:0005462

Show evidence (3 references)

PMID:19032739 SUPPORT

"Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles, skeletal abnormalities, intracranial ectopic calcifications"

Lists intracranial ectopic calcifications as a main clinical manifestation.

PMID:22918513 SUPPORT Human Clinical

"Falx calcification, the most frequent radiological feature, was present in 37% of individuals <20 and 79% of those >20 years."

Pediatric-to-adult cohort shows age-dependent increase in falx calcification frequency.

ORPHA:377 SUPPORT Other

"HP:0005462 | Calcification of falx cerebri | Frequent (79-30%)"

Orphanet's HPO annotation independently classifies calcification of falx cerebri as frequent in Gorlin syndrome.

Neoplasm 2

Medulloblastoma OCCASIONAL HP:0002885

Show evidence (4 references)

PMID:25403219 SUPPORT

"Each SUFU-positive family included a single case of medulloblastoma, whereas only two (1.7%) of 115 individuals with Gorlin syndrome and a PTCH1 mutation developed medulloblastoma."

Quantifies medulloblastoma risk by genotype, showing much higher risk in SUFU carriers.

PMID:29186568 SUPPORT

"Twenty-two patients from 17 families were identified with medulloblastoma and a germline SUFU mutation (median age at diagnosis: 16.5 mo)."

Documents early onset of medulloblastoma in SUFU mutation carriers.

PMID:34888241 SUPPORT Human Clinical

"Nine patients presented with desmoplastic medulloblastomas (DMB), 6 with medulloblastomas with extensive nodularity (MBEN) and one patient with classic medulloblastoma (CMB); all tumors affected the cerebellum, vermis or the fourth ventricle. SHH activation was present in all investigated tumors (14/16);"

Genetically confirmed Gorlin cohort shows that associated medulloblastomas are predominantly SHH-activated infant tumors with DMB or MBEN histology.

+ 1 more reference

Meningioma OCCASIONAL HP:0002858

Show evidence (4 references)

PMID:28596197 SUPPORT Human Clinical

"Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."

Demonstrates that meningioma is significantly enriched in SUFU versus PTCH1 mutation carriers.

PMID:38282294 SUPPORT Human Clinical

"the most common were medulloblastoma (N = 59 patients), BCC (N = 21 patients), and meningioma (N = 19 patients)"

Scoping review of 176 germline SUFU carriers confirming meningioma as one of the three most frequent neoplasms.

PMID:35768194 SUPPORT Human Clinical

"The cumulative risk of an MB, gonadal tumour, BCC and meningioma at age 50 years was: 13.3% (95% CI 6 to 20.1), 4.6% (95% CI 0 to 9.7), 28.5% (95% CI 13.4 to 40.9) and 5.2% (95% CI 0 to 12), respectively."

Large collaborative cohort quantifying cumulative meningioma risk of 5.2% by age 50 in SUFU carriers.

+ 1 more reference

Other 5

Melanocytic Nevi VERY_FREQUENT Melanocytic nevus HP:0000995

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"HP:0000995 | Melanocytic nevus | Very frequent (99-80%)"

Orphanet's HPO annotation classifies melanocytic nevus as very frequent in Gorlin syndrome.

Pectus Deformity OCCASIONAL Abnormal sternum morphology HP:0000766

Show evidence (1 reference)

PMID:9096761 SUPPORT Human Clinical

"hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."

NIH cohort documents pectus deformity in 13% of affected individuals.

Sprengel Anomaly OCCASIONAL HP:0000912

Show evidence (1 reference)

PMID:9096761 SUPPORT Human Clinical

"hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."

NIH cohort documents Sprengel deformity in 11% of affected individuals.

Gonadal Tumors OCCASIONAL Gonadal neoplasm HP:0010785

Show evidence (1 reference)

PMID:35768194 SUPPORT Human Clinical

"Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients)."

Large collaborative cohort documenting gonadal tumors in 11/172 SUFU carriers, with median onset at age 14.

Bridged Sella Turcica FREQUENT HP:0005449

Show evidence (1 reference)

PMID:9096761 SUPPORT Human Clinical

"Important radiological signs included calcification of the falx cerebri in 65%, of the tentorium cerebelli in 20%, bridged sella in 68%, bifid ribs in 26%, hemivertebrae in 15%, fusion of the vertebral bodies in 10%"

Large NIH cohort identifies bridged sella as one of the most common Gorlin radiographic signs.

🧬

Genetic Associations

3

PTCH1 (Causative (Primary))

Gene: PTCH1 hgnc:9585

Autosomal Dominant

Show evidence (3 references)

PMID:28596197 SUPPORT

"A total of 126 patients had a heterozygous pathogenic variant, 9 had SUFU pathogenic variants and 46 had no identified mutation."

Supports predominance of non-SUFU pathogenic variants in this cohort, but the snippet does not explicitly name PTCH1 in the quoted text.

PMID:28596197 SUPPORT

"Patients with a missense variant in PTCH1 were diagnosed later (p=0.03) and were less likely to develop at least 10 BCCs and jaw cysts than those with other pathogenic PTCH1 variants (p=0.03)."

Demonstrates genotype-phenotype correlation with milder disease in missense variant carriers.

CGGV:assertion_2a3f55f5-e39b-4571-a41f-e46ddb8e298d-2018-06-04T170000.000Z SUPPORT Other

ClinGen classifies the PTCH1-nevoid basal cell carcinoma syndrome relationship as definitive with autosomal dominant inheritance.

PTCH2 (Limited ClinGen gene-disease validity assertion)

Gene: PTCH2 hgnc:9586

Autosomal Dominant

Show evidence (1 reference)

CGGV:assertion_d189ca00-ba80-49af-9b2e-8523c8d29a44-2018-10-12T213908.660Z SUPPORT Other

ClinGen records a limited autosomal dominant PTCH2-nevoid basal cell carcinoma syndrome assertion for the same MONDO disease concept, so it is included as lower-confidence structured disease-gene evidence.

SUFU (Causative (Alternative))

Gene: SUFU hgnc:16466

Autosomal Dominant

Show evidence (2 references)

PMID:25403219 SUPPORT

"We demonstrate convincing evidence that SUFU mutations can cause classical Gorlin syndrome."

Establishes SUFU as a causative gene for Gorlin syndrome.

PMID:28596197 SUPPORT

"Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."

Documents distinct phenotypic spectrum in SUFU versus PTCH1 mutation carriers.

🗃️

External Assertions

1

Orphanet Gorlin syndrome structured record

Orphanet structured disease record ORPHA:377

Orphanet records Gorlin syndrome as ORPHA:377 and provides external cross-references supporting this entry's disease identity.

Show evidence (2 references)

ORPHA:377 SUPPORT Other

"MONDO:0007187 | Exact"

Orphanet lists the MONDO disease identifier as an exact cross-reference.

ORPHA:377 SUPPORT Other

"OMIM:109400 | Exact"

Orphanet lists the OMIM disease identifier as an exact cross-reference.

💊

Medical Actions

8

Surgical Excision

Action: Excision NCIT:C15232

Surgical removal of basal cell carcinomas is the primary treatment. Mohs micrographic surgery may be preferred for facial lesions to preserve tissue. Given the multiplicity of tumors, repeated surgeries are often necessary.

Target Phenotypes: Basal cell carcinoma HP:0002671 Odontogenic keratocysts of the jaw HP:0010603

Vismodegib

Action: targeted therapy Ontology label: Targeted Therapy NCIT:C93352

Agent: vismodegib CHEBI:66903

Hedgehog pathway inhibitor approved for locally advanced BCC. Can reduce tumor burden in patients with multiple BCCs, but side effects (muscle spasms, dysgeusia, alopecia) limit long-term use. Tumors may regrow after discontinuation.

Mechanism Target:

INHIBITS SMO Constitutive Activation — Vismodegib binds SMO and restores its inhibited conformation, blocking constitutive Hedgehog pathway output in PTCH1-driven Gorlin BCCs. Because SUFU-mutant disease constitutively activates GLI downstream of SMO, SMO inhibitors have limited efficacy in SUFU-driven tumors; resistance can also emerge via SMO resistance mutations or downstream GLI amplification that bypasses this node.

Target Phenotypes: Basal cell carcinoma HP:0002671

Show evidence (2 references)

PMID:22670904 SUPPORT

"Vismodegib reduces the basal-cell carcinoma tumor burden and blocks growth of new basal-cell carcinomas in patients with the basal-cell nevus syndrome."

Randomized controlled trial demonstrating efficacy of vismodegib in reducing BCC burden in Gorlin syndrome.

PMID:22670904 SUPPORT

"The adverse events associated with treatment led to discontinuation in over half of treated patients."

Documents significant tolerability issues with vismodegib leading to high discontinuation rates.

Sonidegib

Action: targeted therapy Ontology label: Targeted Therapy NCIT:C93352

Agent: sonidegib CHEBI:90863

Alternative SMO inhibitor for locally advanced BCC. Similar mechanism and side effect profile to vismodegib.

Mechanism Target:

INHIBITS SMO Constitutive Activation — Sonidegib likewise binds SMO, blocking constitutive Hedgehog signaling in PTCH1-driven Gorlin BCCs with a similar mechanism and resistance profile to vismodegib.

Target Phenotypes: Basal cell carcinoma HP:0002671

Topical Patidegib (Investigational)

Action: topical pharmacotherapy Ontology label: Pharmacotherapy NCIT:C15986

Agent: patidegib NCIT:C80063

Patidegib is a cyclopamine-derived SMO/Hedgehog inhibitor formulated as a topical gel to deliver local anti-BCC activity while keeping systemic drug levels low, aiming to avoid the muscle spasms, dysgeusia, and alopecia that drive discontinuation of oral Hedgehog inhibitors. A randomized double-blind phase IIA trial in Gorlin syndrome suggested reduced numbers of new surgically eligible BCCs with minimal adverse effects; it remains investigational and not yet approved.

Mechanism Target:

INHIBITS SMO Constitutive Activation — Patidegib binds SMO and dampens constitutive Hedgehog output locally in the skin; topical delivery is intended to suppress field BCC formation without the systemic exposure that limits oral SMO antagonists.

Target Phenotypes: Basal cell carcinoma HP:0002671

Show evidence (2 references)

PMID:39545486 SUPPORT Human Clinical

"Post hoc analyses suggested that patidegib topical gel reduced the number of new, surgically eligible BCCs and the level of HH signalling, with minimal adverse effects."

Phase IIA randomized trial in Gorlin syndrome supports topical patidegib as an emerging field therapy that reduces new BCCs with minimal systemic toxicity.

PMID:39545486 SUPPORT Human Clinical

"we developed a gel containing a small cyclopamine-derived molecule that can be applied topically in expectation that this mode of delivery can reduce the burden of BCCs without producing the systemic adverse effects that cause patients to stop oral HHi treatment."

Documents the rationale for topical delivery to decouple local Hedgehog blockade from the systemic toxicity of oral SMO inhibitors.

Laser Ablation Therapy

Action: laser ablation therapy Ontology label: Laser Ablation NCIT:C111241

Laser ablation and photodynamic therapy may be useful for treating multiple superficial BCCs with acceptable cosmetic outcomes. Less effective for nodular or aggressive subtypes.

Target Phenotypes: Basal cell carcinoma HP:0002671

Show evidence (1 reference)

PMID:19032739 SUPPORT

"Surgery for BBCs is indicated when the number of lesions is limited; other treatments include laser ablation, photodynamic therapy and topical chemotherapy."

Supports laser-based local therapy as a lesion-directed option for multiple superficial BCCs in Gorlin syndrome.

Topical Therapy

Action: topical pharmacotherapy Ontology label: Pharmacotherapy NCIT:C15986

Topical imiquimod or 5-fluorouracil may be used for superficial BCCs to reduce surgical burden.

Target Phenotypes: Basal cell carcinoma HP:0002671

Show evidence (1 reference)

PMID:19032739 SUPPORT

"Surgery for BBCs is indicated when the number of lesions is limited; other treatments include laser ablation, photodynamic therapy and topical chemotherapy."

Supports topical chemotherapy as a non-surgical option for superficial BCCs in Gorlin syndrome.

Sun Avoidance

Action: sunlight avoidance Ontology label: Lifestyle Therapy NCIT:C15900

Rigorous sun protection with sunscreen, protective clothing, and sunlight avoidance is essential to reduce the development of new BCCs.

Target Phenotypes: Basal cell carcinoma HP:0002671

Show evidence (1 reference)

PMID:19032739 SUPPORT

"Patients with NBCCS should strictly avoid an excessive sun exposure."

Supports UV avoidance as a preventive intervention to reduce new BCC formation in Gorlin syndrome.

Genetic Counseling

Action: Genetic Counseling NCIT:C15240

Given autosomal dominant inheritance and 50% recurrence risk, genetic counseling is recommended for affected individuals and at-risk family members.

🌍

Environmental Factors

2

Ultraviolet Radiation

UV exposure accelerates development and increases the number of basal cell carcinomas in affected individuals. Sun protection is a critical component of management.

Show evidence (1 reference)

PMID:19032739 SUPPORT

"Patients with NBCCS should strictly avoid an excessive sun exposure."

Clinical recommendation to avoid sun exposure to prevent BCC development.

Mechanism Target:

TRIGGERS PTCH1 Somatic Second-Hit Loss — The germline first hit is inherited and unavoidable; ultraviolet light supplies the somatic second hit in sun-exposed skin, via DNA photoproducts and their mis-repair. That is why tumour burden tracks sun exposure in an otherwise fixed genotype.

Show evidence (1 reference)

PMID:12007715 SUPPORT Human Clinical

"p53 and PTCH mutations were detected at a frequency of 33 and 40%, respectively, and the mutations were predominantly UV-signature transition, C-->T transitions at dipyrimidine sites and CC-->TT tandem mutations."

PTCH mutations recovered from basal cell carcinomas carry the C to T and CC to TT changes at dipyrimidine sites that only ultraviolet light produces, so ultraviolet exposure is the mutagen inactivating the gene. The series is sporadic disease; the inference here is that the same mutagenic route supplies the somatic hit in germline carriers.

Ionizing Radiation

Patients with Gorlin syndrome are exquisitely sensitive to ionizing radiation, which can induce numerous BCCs in the radiation field. Radiotherapy should be avoided when possible, including for medulloblastoma treatment.

Show evidence (2 references)

PMID:6837723 SUPPORT

"Clinical follow-up of these patients, treated with radiotherapy, revealed a predisposition to radiogenic basal cell carcinomas with an unusually short latent period of 6 months to 3 years."

Documents radiation-induced BCCs in NBCCS patients with abnormally short latency.

PMID:19032739 SUPPORT

"Radiotherapy should be avoided."

Clinical recommendation to avoid radiotherapy in NBCCS patients due to radiation sensitivity.

Mechanism Target:

TRIGGERS PTCH1 Somatic Second-Hit Loss — Therapeutic irradiation supplies the same somatic second hit through DNA double-strand breaks, which is why radiotherapy in these patients produces basal cell carcinomas within the treated field.

Show evidence (1 reference)

PMID:6837723 SUPPORT Human Clinical

"Clinical follow-up of these patients, treated with radiotherapy, revealed a predisposition to radiogenic basal cell carcinomas with an unusually short latent period of 6 months to 3 years."

Documents a predisposition to radiogenic basal cell carcinomas in irradiated patients, tumours arising in the field where radiation delivered the somatic damage.

🔬

Diagnosis

2

Clinical Criteria

Diagnosis is based on clinical criteria. Major criteria include multiple (>2) BCCs or one BCC before age 20, odontogenic keratocysts, palmar/plantar pits, calcification of falx cerebri, and first-degree relative with NBCCS. Minor criteria include medulloblastoma, ovarian fibroma, macrocephaly, and various skeletal anomalies. Two major criteria or one major plus two minor criteria suggest the diagnosis.

Genetic Testing

Molecular testing for PTCH1 and SUFU mutations can confirm the diagnosis and is particularly useful for at-risk family members and in atypical presentations.

📈

Progression

2

Adolescent onset

Age: Adolescent

Orphanet lists adolescent onset as part of the natural history.

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"- Age of onset: Adolescent"

Orphanet records adolescent age of onset for Gorlin syndrome.

Adult onset

Age: Adult

Orphanet also lists adult onset, consistent with age-dependent recognition of tumor and radiographic manifestations.

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"- Age of onset: Adult"

Orphanet records adult age of onset for Gorlin syndrome.

📊

Prevalence

2

Global

Point Prevalence 0.390625–1.754386 per 100,000 1–9 per 100,000

Estimated prevalence varies from 1/57,000 to 1/256,000, with a male-to-female ratio of 1:1. Approximately 70-80% of cases are familial, with 20-30% arising from de novo mutations.

Show evidence (1 reference)

PMID:19032739 SUPPORT

"The estimated prevalence varies from 1/57,000 to 1/256,000, with a male-to-female ratio of 1:1."

Documents prevalence estimates from Orphanet review.

Worldwide (Orphanet)

Point Prevalence 1.0–9.0 per 100,000 1–9 per 100,000

Orphanet classifies worldwide point prevalence as 1-9 per 100,000 using PMID:24403894 plus expert input.

Show evidence (1 reference)

ORPHA:377 SUPPORT Other

"1-9 / 100 000 | Worldwide | Point prevalence | PMID:24403894,EXPERT"

Orphanet's epidemiology table provides a worldwide point-prevalence class for Gorlin syndrome.

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name: Gorlin Syndrome
creation_date: '2026-02-03T04:23:32Z'
description: >-
  Gorlin syndrome (nevoid basal cell carcinoma syndrome, NBCCS) is an autosomal dominant
  hereditary cancer predisposition syndrome caused most often by germline loss-of-function
  variants in PTCH1 and less often by pathogenic variants in SUFU, two negative regulators
  of Hedgehog signaling. The syndrome is characterized by multiple basal cell carcinomas,
  odontogenic keratocysts of the jaw, palmar and plantar pits, characteristic craniofacial
  and skeletal abnormalities, ectopic falx calcification, and genotype-specific risk
  of
  SHH-activated medulloblastoma. Constitutive GLI-dependent Hedgehog output links
  the
  developmental and neoplastic manifestations. Management includes surveillance for
  early
  detection of malignancies, surgical removal of tumors, and Hedgehog pathway inhibitors
  for advanced basal cell carcinomas.
category: Mendelian
parents:
- hereditary cancer predisposition syndrome
- Hedgehog pathway disease
disease_term:
  preferred_term: nevoid basal cell carcinoma syndrome
  term:
    id: MONDO:0007187
    label: nevoid basal cell carcinoma syndrome
mappings:
  mondo_mappings:
  - term:
      id: MONDO:0007187
      label: nevoid basal cell carcinoma syndrome
    mapping_predicate: skos:exactMatch
    mapping_source: Orphanet ORPHA:377
    mapping_justification: >-
      Orphanet lists MONDO:0007187 as an exact cross-reference for the
      ORPHA:377 Gorlin syndrome record.
external_assertions:
- name: Orphanet Gorlin syndrome structured record
  source: Orphanet
  assertion_type: structured_disease_record
  external_id: ORPHA:377
  url: http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=377
  description: >-
    Orphanet records Gorlin syndrome as ORPHA:377 and provides external
    cross-references supporting this entry's disease identity.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "MONDO:0007187 | Exact"
    explanation: Orphanet lists the MONDO disease identifier as an exact cross-reference.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "OMIM:109400 | Exact"
    explanation: Orphanet lists the OMIM disease identifier as an exact cross-reference.
synonyms:
- Nevoid basal cell carcinoma syndrome
- NBCCS
- Basal cell nevus syndrome
- Gorlin-Goltz syndrome
definitions:
- name: Orphanet definition of Gorlin syndrome
  definition_type: CASE_DEFINITION
  description: >-
    Gorlin syndrome is a hereditary hamartosis syndrome with early-onset basal
    cell carcinomas, jaw keratocysts, and skeletal abnormalities.
  scope: Orphanet structured disease definition
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "A rare hereditary disorder due to autosomal dominant transmission with hamartosis characterized by multiple early-onset basal cell carcinoma (BCC), multiple jaw keratocysts and skeletal abnormalities."
    explanation: Orphanet's definition supports the high-level hereditary syndrome framing and core clinical triad.
has_subtypes:
- name: PTCH1-related
  description: >-
    The predominant form (~85-95% of cases), caused by germline PTCH1 mutations.
    Characterized by high rates of basal cell carcinomas, odontogenic keratocysts,
    skeletal anomalies, and calcification of the falx cerebri. Medulloblastoma risk
    is low (<2%). Many individuals have a recognizable facial appearance. Missense
    variants are associated with later diagnosis and milder phenotype.
  evidence:
  - reference: PMID:20301330
    reference_title: "Nevoid Basal Cell Carcinoma Syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Many individuals have a recognizable appearance with macrocephaly, frontal bossing, coarse facial features, and facial milia."
    explanation: >-
      GeneReviews characterizes recognizable facial appearance in PTCH1-related NBCCS
      as common ("many individuals") without specifying a proportion; the unsourced
      "~60%" figure was removed to match the cited evidence.
- name: SUFU-related
  description: >-
    A minority form (~5% of cases), caused by germline SUFU mutations. Characterized
    by milder BCC burden, absence of jaw keratocysts, but markedly higher risk of
    medulloblastoma (up to 33%), meningioma (~11%), and gonadal tumors. Facial
    features are subtler. Often presents in early childhood with medulloblastoma.
  evidence:
  - reference: PMID:20301330
    reference_title: "Nevoid Basal Cell Carcinoma Syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The risk of developing medulloblastoma is substantially higher in individuals with an SUFU pathogenic variant (33%) than in those with a PTCH1 pathogenic variant (<2%)."
    explanation: >-
      GeneReviews quantifies the 33% medulloblastoma penetrance for SUFU pathogenic variant
      carriers versus <2% for PTCH1, directly supporting the comparative risk figures in
      the SUFU-related subtype description.
  - reference: PMID:38282294
    reference_title: "Medulloblastoma and other neoplasms in patients with heterozygous germline SUFU variants: A scoping review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "the most common were medulloblastoma (N = 59 patients), BCC (N = 21 patients), and meningioma (N = 19 patients)"
    explanation: >-
      In this scoping review of 176 confirmed SUFU+/- carriers, meningioma occurred in
      19 patients (19/176 ≈ 11%), supporting the ~11% meningioma figure in the
      SUFU-related subtype description.
prevalence:
- population: Global
  measure_type: POINT_PREVALENCE
  prevalence_class: BAND_1_9_PER_100000
  rate_low: 0.390625
  rate_high: 1.754386
  percentage: 1 in 57,000 to 1 in 256,000
  notes: >-
    Estimated prevalence varies from 1/57,000 to 1/256,000, with a male-to-female
    ratio of 1:1. Approximately 70-80% of cases are familial, with 20-30% arising
    from de novo mutations.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "The estimated prevalence varies from 1/57,000 to 1/256,000, with a male-to-female ratio of 1:1."
    explanation: Documents prevalence estimates from Orphanet review.
- population: Worldwide (Orphanet)
  measure_type: POINT_PREVALENCE
  prevalence_class: BAND_1_9_PER_100000
  rate_low: 1.0
  rate_high: 9.0
  percentage: 1-9 / 100 000
  notes: >-
    Orphanet classifies worldwide point prevalence as 1-9 per 100,000 using
    PMID:24403894 plus expert input.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "1-9 / 100 000 | Worldwide | Point prevalence | PMID:24403894,EXPERT"
    explanation: Orphanet's epidemiology table provides a worldwide point-prevalence class for Gorlin syndrome.
inheritance:
- name: Autosomal Dominant
  inheritance_term:
    preferred_term: Autosomal dominant inheritance
    term:
      id: HP:0000006
      label: Autosomal dominant inheritance
  description: >-
    Gorlin syndrome follows autosomal dominant inheritance with high penetrance
    but variable expressivity. Approximately 20-30% of cases arise from de novo mutations.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "NBCCS is caused by mutations in the PTCH1 gene and is transmitted as an autosomal dominant trait with complete penetrance and variable expressivity."
    explanation: Documents autosomal dominant inheritance with complete penetrance.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "- Autosomal dominant"
    explanation: Orphanet directly records autosomal dominant inheritance for Gorlin syndrome.
progression:
- phase: Adolescent onset
  age_range: Adolescent
  notes: Orphanet lists adolescent onset as part of the natural history.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "- Age of onset: Adolescent"
    explanation: Orphanet records adolescent age of onset for Gorlin syndrome.
- phase: Adult onset
  age_range: Adult
  notes: Orphanet also lists adult onset, consistent with age-dependent recognition of tumor and radiographic manifestations.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "- Age of onset: Adult"
    explanation: Orphanet records adult age of onset for Gorlin syndrome.
pathophysiology:
- name: PTCH1 Germline First-Hit Loss-of-Function
  biological_scale: MOLECULAR
  description: >-
    PTCH1 encodes Patched 1, a 12-pass transmembrane receptor that normally suppresses
    Smoothened (SMO) in the absence of Hedgehog ligand. Germline heterozygous loss-of-function
    mutations in PTCH1 predispose to tumors following Knudson's two-hit model. Loss
    of the
    remaining wild-type allele in somatic cells leads to constitutive Hedgehog pathway
    activation and tumor development.
  conforms_to: "hedgehog_pathway_activation#Loss of Hedgehog Pathway Negative Regulation"
  genetic_context:
    gene:
      preferred_term: PTCH1
      term:
        id: hgnc:9585
        label: PTCH1
    functional_impact_category: LOSS_OF_FUNCTION
    description: >-
      Germline plus somatic (Knudson two-hit) loss-of-function of the
      tumor-suppressor negative regulator PTCH1; gene-level loss produces net
      Hedgehog pathway activation.
  gene:
    preferred_term: PTCH1
    description: Patched 1, the canonical Hedgehog receptor that restrains Smoothened signaling.
    term:
      id: hgnc:9585
      label: PTCH1
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "NBCCS is caused by mutations in the PTCH1 gene and is transmitted as an autosomal dominant trait with complete penetrance and variable expressivity."
    explanation: Establishes PTCH1 as the causative gene for NBCCS with autosomal dominant inheritance.
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    snippet: "Heterozygous germline variants in PTCH1 and SUFU encoding components of the Sonic hedgehog pathway explain the majority of cases."
    explanation: Confirms PTCH1 germline variants as the primary genetic cause of Gorlin syndrome.
  - reference: CGDS:HGNC_9585
    reference_title: "PTCH1 dosage sensitivity"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Loss of function variants within this gene have been associated with nevoid basal cell carcinoma syndrome."
    explanation: ClinGen dosage sensitivity supports PTCH1 haploinsufficiency/loss-of-function as a mechanism for nevoid basal cell carcinoma syndrome.
  downstream:
  - target: PTCH1 Somatic Second-Hit Loss
    description: The constitutional heterozygous PTCH1 lesion is the first of the two hits required for tumor-cell Hedgehog derepression; a somatic loss of the remaining wild-type allele in a susceptible cell completes biallelic inactivation.
    causal_link_type: DIRECT
- name: PTCH1 Somatic Second-Hit Loss
  conforms_to: "germline_two_hit_tumor_predisposition#Somatic Second-Hit Inactivation of the Wild-Type Allele"
  biological_scale: MOLECULAR
  description: >-
    Somatic loss of the remaining wild-type PTCH1 allele in a susceptible cell
    — the Knudson second hit that completes biallelic PTCH1 inactivation. Loss
    of heterozygosity at 9q22 is the classic mechanism in Gorlin BCCs. Once
    both alleles are inactivated, Smoothened is released from tonic Patched
    inhibition and accumulates constitutively at the primary cilium.
  gene:
    preferred_term: PTCH1
    description: Patched 1, the canonical Hedgehog receptor that restrains Smoothened signaling.
    term:
      id: hgnc:9585
      label: PTCH1
  cell_types:
  - preferred_term: basal cell of epidermis
    term:
      id: CL:0002187
      label: basal cell of epidermis
  evidence:
  - reference: PMID:8681379
    reference_title: "Mutations of the human homolog of Drosophila patched in the nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    snippet: "Familial and sporadic BCCs display loss of heterozygosity in this region, consistent with the gene being a tumor suppressor."
    explanation: Direct LOH evidence for biallelic PTCH1 inactivation (Knudson second hit) in Gorlin-associated BCCs.
  downstream:
  - target: SMO Constitutive Activation
    description: Biallelic loss of PTCH1 releases SMO from tonic inhibition at the primary cilium, allowing SMO accumulation and constitutive downstream signaling
    causal_link_type: DIRECT
    hypothesis_groups:
    - canonical_smo_dependent_model
- name: SUFU Germline Mutations
  biological_scale: MOLECULAR
  description: >-
    A minority of Gorlin syndrome cases (approximately 5%) are caused by germline
    mutations in SUFU (Suppressor of Fused), which encodes a negative regulator of
    GLI transcription factors. SUFU mutations are associated with markedly higher
    risk of
    medulloblastoma (up to 20-fold higher) compared to PTCH1 mutations, with tumors
    typically
    occurring before age 3 years.
  conforms_to: "hedgehog_pathway_activation#Loss of Hedgehog Pathway Negative Regulation"
  genetic_context:
    gene:
      preferred_term: SUFU
      term:
        id: hgnc:16466
        label: SUFU
    functional_impact_category: LOSS_OF_FUNCTION
    description: >-
      Loss-of-function of the negative regulator SUFU; because SUFU acts
      downstream of SMO, the gene-level loss activates GLI output independently
      of Smoothened (the SMO-inhibitor-resistant branch).
  gene:
    preferred_term: SUFU
    description: Suppressor of fused, a negative regulator that restrains GLI transcription factors.
    term:
      id: hgnc:16466
      label: SUFU
  evidence:
  - reference: PMID:25403219
    reference_title: "Germline mutations in SUFU cause Gorlin syndrome-associated childhood medulloblastoma and redefine the risk associated with PTCH1 mutations."
    supports: SUPPORT
    snippet: "We found a < 2% risk in PTCH1 mutation-positive individuals, with a risk up to 20× higher in SUFU mutation-positive individuals."
    explanation: Demonstrates that SUFU mutations confer dramatically higher medulloblastoma risk than PTCH1 mutations.
  - reference: PMID:29186568
    reference_title: "Germline SUFU mutation carriers and medulloblastoma: clinical characteristics, cancer risk, and prognosis."
    supports: SUPPORT
    snippet: "Germline SUFU mutations strongly predispose to medulloblastoma in the first years of life, with worse prognosis than usually observed for SHH medulloblastoma."
    explanation: Confirms high medulloblastoma risk and poor prognosis in SUFU mutation carriers.
  biological_processes:
  - preferred_term: negative regulation of smoothened signaling pathway
    modifier: DECREASED
    term:
      id: GO:0045879
      label: negative regulation of smoothened signaling pathway
  downstream:
  - target: GLI Transcription Factor Activation
    description: Loss of SUFU-mediated GLI sequestration directly releases GLI1 and GLI2 to the nucleus, bypassing SMO-level regulation and making the pathway insensitive to SMO inhibitors such as vismodegib and sonidegib
    causal_link_type: DIRECT
    hypothesis_groups:
    - sufu_smo_independent_gli_model
  - target: SUFU-Associated Meningioma Predisposition
    description: SUFU germline LOF predisposes to meningioma
  - target: SUFU-Associated Ovarian Fibroma Predisposition
    description: SUFU germline LOF predisposes to ovarian fibroma
  - target: SUFU-Associated Gonadal Tumor Predisposition
    description: SUFU germline LOF predisposes to gonadal tumors
- name: SMO Constitutive Activation
  biological_scale: MOLECULAR
  description: >-
    PTCH1 normally suppresses Smoothened (SMO) by preventing its accumulation in
    the primary ciliary membrane. When PTCH1 is lost via Knudson second-hit
    inactivation, SMO is no longer restrained and accumulates constitutively at
    the cilium, triggering downstream GLI signaling. This SMO-active state is
    the direct molecular target of the approved Hedgehog-pathway inhibitors
    vismodegib and sonidegib: both drugs bind SMO and restore its inhibited
    conformation. SUFU-mutant Gorlin disease bypasses this node entirely,
    predicting reduced efficacy of SMO inhibitors for that genotype.
  conforms_to: "hedgehog_pathway_activation#Constitutive Smoothened Activity"
  evidence:
  - reference: PMID:37947611
    reference_title: "Signaling Pathways and Therapeutic Strategies in Advanced Basal Cell Carcinoma."
    supports: SUPPORT
    snippet: "Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals."
    explanation: >-
      Establishes PTCH and SMO as the upstream pathway lesions driving GLI activation in BCC;
      supports the mechanistic model that PTCH1 loss derepresses SMO constitutive activity.
  - reference: PMID:22670904
    reference_title: "Inhibiting the hedgehog pathway in patients with the basal-cell nevus syndrome."
    supports: SUPPORT
    snippet: "Dysregulated hedgehog signaling is the pivotal molecular abnormality underlying basal-cell carcinomas. Vismodegib is a new orally administered hedgehog-pathway inhibitor that produces objective responses in locally advanced and metastatic basal-cell carcinomas."
    explanation: >-
      Confirms that vismodegib targets dysregulated Hedgehog signaling (acting at SMO) and is
      efficacious in Gorlin syndrome BCCs; supports this node as the druggable point of intervention.
  cell_types:
  - preferred_term: basal cell of epidermis
    term:
      id: CL:0002187
      label: basal cell of epidermis
  biological_processes:
  - preferred_term: smoothened signaling pathway
    modifier: INCREASED
    term:
      id: GO:0007224
      label: smoothened signaling pathway
  downstream:
  - target: GLI Transcription Factor Activation
    description: >-
      Constitutively active SMO suppresses the PKA-GSK3B-BTRC phosphorylation cascade
      that processes GLI3 to its repressor form, and promotes SUFU release of GLI1/GLI2,
      driving their nuclear import and transcriptional activity
    causal_link_type: DIRECT
    hypothesis_groups:
    - canonical_smo_dependent_model
- name: GLI Transcription Factor Activation
  biological_scale: MOLECULAR
  description: >-
    Both PTCH1 loss (via SMO derepression) and SUFU loss (via direct release of
    GLI sequestration) converge on constitutive nuclear accumulation of GLI1 and
    GLI2. GLI1 transcriptionally activates pro-proliferative targets including CCND1,
    BCL2, and MYCN, and drives a positive-feedback loop by inducing PTCH1 expression.
    Loss of the GLI3 repressor arm (GLI3R, which requires PKA-GSK3B-BTRC-mediated
    partial proteolysis) compounds the transcriptional imbalance. This convergent GLI
    activation node links both genotypic etiologies to the full spectrum of Gorlin
    developmental and neoplastic phenotypes. Resistance to SMO inhibitors can emerge
    through amplification or activation of GLI downstream of SMO, a mechanism invisible
    in schema representations that bundle SMO and GLI as a single pathway node.
  conforms_to: "hedgehog_pathway_activation#Constitutive GLI Transcriptional Output"
  evidence:
  - reference: PMID:37947611
    reference_title: "Signaling Pathways and Therapeutic Strategies in Advanced Basal Cell Carcinoma."
    supports: SUPPORT
    snippet: "Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals."
    explanation: >-
      Confirms that PTCH, SUFU, and SMO mutations all converge on aberrant GLI transcription factor
      activation, establishing the GLI node as the functional convergence point of multiple upstream etiologies.
  cell_types:
  - preferred_term: basal cell of epidermis
    term:
      id: CL:0002187
      label: basal cell of epidermis
  biological_processes:
  - preferred_term: smoothened signaling pathway
    modifier: INCREASED
    term:
      id: GO:0007224
      label: smoothened signaling pathway
  - preferred_term: cell population proliferation
    modifier: INCREASED
    term:
      id: GO:0008283
      label: cell population proliferation
  downstream:
  - target: Multiple Basal Cell Carcinomas
    description: Constitutive GLI signaling in epidermal basal cells promotes repeated BCC initiation
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    hypothesis_groups:
    - canonical_smo_dependent_model
    - gli_bypass_resistance_model
  - target: Palmoplantar Keratinization Abnormalities
    description: Aberrant pathway output disrupts palmoplantar keratinocyte differentiation and surface integrity
  - target: Odontogenic Keratocysts
    description: Hedgehog dysregulation alters odontogenic epithelial growth and jaw cyst formation
  - target: SHH-Responsive Cerebellar Progenitor Expansion
    description: Excess pathway output sustains proliferation in cerebellar precursors
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    hypothesis_groups:
    - sufu_smo_independent_gli_model
  - target: Hedgehog-Driven Osteogenic Dysregulation
    description: Developmental Hedgehog hyperactivity perturbs craniofacial and skeletal patterning
  - target: Hedgehog-Driven Craniofacial Patterning Dysregulation
    description: Developmental Hedgehog dysregulation perturbs neural-crest-driven growth and patterning of the face and skull base
  - target: Hedgehog-Dependent Ocular Developmental Dysregulation
    description: Dysregulated Hedgehog output alters optic vesicle patterning and lens differentiation during eye development
  - target: Hedgehog-Dependent Secondary Palate Development Disruption
    description: Abnormal Hedgehog signaling perturbs palatal morphogenesis and increases cleft risk
  - target: Hedgehog-Driven Mesenchymal Tumor Predisposition
    description: Constitutive pathway activation broadens susceptibility to benign mesenchymal tumors such as fibromas
- name: Palmoplantar Keratinization Abnormalities
  biological_scale: CELLULAR
  description: >-
    Palmoplantar skin in Gorlin syndrome shows abnormal keratinization and surface
    differentiation, consistent with the characteristic palmar and plantar pits.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles"
    explanation: Reviews palmoplantar keratinization abnormalities as a core manifestation of Gorlin syndrome.
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Palmar pits and plantar pits were seen in 87%."
    explanation: Large NIH cohort confirms that pits are a common clinical expression of the palmoplantar epithelial abnormality.
  cell_types:
  - preferred_term: keratinocyte
    term:
      id: CL:0000312
      label: keratinocyte
  biological_processes:
  - preferred_term: keratinization
    modifier: ABNORMAL
    term:
      id: GO:0031424
      label: keratinization
  downstream:
  - target: Palmar Pits
    description: Focal palmoplantar epithelial defects manifest clinically as palmar pits
  - target: Plantar Pits
    description: Similar keratinization defects on the soles produce plantar pits
- name: SHH-Responsive Cerebellar Progenitor Expansion
  biological_scale: CELLULAR
  description: >-
    Sonic Hedgehog normally drives proliferation of cerebellar granule cell precursors
    during development. In Gorlin syndrome, constitutive pathway activation in this
    lineage creates a substrate for early-childhood SHH medulloblastoma, particularly
    in SUFU-related disease.
  evidence:
  - reference: PMID:10027293
    reference_title: "Control of neuronal precursor proliferation in the cerebellum by Sonic Hedgehog."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Sonic hedgehog (Shh), which is made by Purkinje cells, regulates the division of granule cell precursors (GCPs)."
    explanation: Foundational cerebellar developmental evidence that SHH controls granule cell precursor proliferation, the lineage exploited in Gorlin-associated medulloblastoma.
  - reference: PMID:32747535
    reference_title: "Modeling SHH-driven medulloblastoma with patient iPS cell-derived neural stem cells."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "We found that Gorlin NES cells formed tumors in mouse cerebellum mimicking human medulloblastoma."
    explanation: Disease-specific patient iPSC model shows that Gorlin neural stem cells can generate medulloblastoma-like tumors in the cerebellar environment.
  cell_types:
  - preferred_term: cerebellar granule cell
    term:
      id: CL:0001031
      label: cerebellar granule cell
  biological_processes:
  - preferred_term: cell population proliferation
    modifier: INCREASED
    term:
      id: GO:0008283
      label: cell population proliferation
  - preferred_term: cerebellum development
    modifier: ABNORMAL
    term:
      id: GO:0021549
      label: cerebellum development
  downstream:
  - target: Medulloblastoma
    description: Persistent SHH dependence in cerebellar precursor populations drives infant medulloblastoma risk
- name: Hedgehog-Driven Osteogenic Dysregulation
  biological_scale: CELLULAR
  description: >-
    Constitutive Hedgehog signaling also perturbs osteoblast differentiation and
    skeletal patterning. Patient-derived PTCH1-mutant iPSCs show constitutive Hh
    activity and hypersensitivity to osteogenic induction, providing a mechanistic
    link to macrocephaly, rib and vertebral anomalies, pectus deformity, Sprengel
    anomaly, and falx calcification.
  evidence:
  - reference: PMID:29088246
    reference_title: "Gorlin syndrome-derived induced pluripotent stem cells are hypersensitive to hedgehog-mediated osteogenic induction."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "We propose that Hh signaling is constituently active in iPSCs from Gorlin syndrome patients, enhancing their response to osteogenic induction and contributing to disease-associated abnormalities."
    explanation: Patient-derived PTCH1-mutant iPSC data support constitutive Hedgehog activity causing abnormal osteogenic responses relevant to the Gorlin skeletal phenotype.
  cell_types:
  - preferred_term: osteoblast
    term:
      id: CL:0000062
      label: osteoblast
  biological_processes:
  - preferred_term: osteoblast differentiation
    modifier: ABNORMAL
    term:
      id: GO:0001649
      label: osteoblast differentiation
  downstream:
  - target: Macrocephaly
    description: Altered craniofacial growth contributes to enlarged head circumference
  - target: Rib Anomalies
    description: Abnormal axial skeletal patterning can produce bifid, splayed, or fused ribs
  - target: Vertebral Anomalies
    description: Abnormal vertebral development leads to segmentation and shape defects
  - target: Pectus Deformity
    description: Chest wall development is perturbed as part of the skeletal phenotype
  - target: Sprengel Anomaly
    description: Shoulder girdle patterning defects contribute to elevated scapula morphology
  - target: Calcification of Falx Cerebri
    description: Ectopic intracranial calcification reflects abnormal ossification and calcification responses
- name: Hedgehog-Driven Craniofacial Patterning Dysregulation
  biological_scale: TISSUE
  description: >-
    Hedgehog pathway dysregulation in cranial neural crest-derived tissues perturbs
    the patterning and growth of facial primordia and skull-base structures,
    providing a developmental basis for the characteristic craniofacial gestalt.
  evidence:
  - reference: PMID:15107405
    reference_title: "Hedgehog signaling in the neural crest cells regulates the patterning and growth of facial primordia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Together, our results demonstrate that Hh signaling in NCCs is essential for normal patterning and growth of the face."
    explanation: Neural crest-restricted model establishes Hedgehog signaling as a core determinant of facial growth and patterning.
  - reference: PMID:37481904
    reference_title: "Sonic hedgehog signaling in craniofacial development."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Studies in animal models have revealed that SHH signaling plays crucial roles at multiple stages of craniofacial morphogenesis, from cranial neural crest cell survival to growth and patterning of the facial primordia"
    explanation: Recent review summarizes the broad dependence of craniofacial morphogenesis on Hedgehog signaling.
  cell_types:
  - preferred_term: neural crest cell
    term:
      id: CL:0011012
      label: neural crest cell
  biological_processes:
  - preferred_term: neural crest cell migration
    modifier: ABNORMAL
    term:
      id: GO:0001755
      label: neural crest cell migration
  - preferred_term: mesenchymal cell proliferation
    modifier: ABNORMAL
    term:
      id: GO:0010463
      label: mesenchymal cell proliferation
  downstream:
  - target: Macrocephaly
    description: Altered craniofacial growth contributes to enlarged head circumference
  - target: Hypertelorism
    description: Abnormal facial primordia patterning widens the orbital spacing
  - target: Frontal Bossing
    description: Dysregulated skull and forehead growth contributes to frontal prominence
  - target: Coarse Facial Features
    description: Cumulative craniofacial patterning defects produce the recognizable coarse facies
  - target: Bridged Sella Turcica
    description: Skull-base patterning abnormalities contribute to sellar bridging on imaging
- name: Hedgehog-Dependent Ocular Developmental Dysregulation
  conforms_to: "ocular_morphogenesis_failure#Eye Field Specification and Optic Vesicle Patterning Perturbation"
  biological_scale: TISSUE
  description: >-
    Dysregulated Hedgehog pathway activity perturbs optic vesicle patterning and
    lens differentiation during development, providing a mechanistic bridge to
    the ocular phenotype in Gorlin syndrome.
  evidence:
  - reference: PMID:18479681
    reference_title: "Zebrafish blowout provides genetic evidence for Patched1-mediated negative regulation of Hedgehog signaling within the proximal optic vesicle of the vertebrate eye."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "These observations highlight the critical role that Hedgehog pathway activity plays in mediating patterning of the proximal/distal axis of the optic vesicle during the early phases of eye development"
    explanation: Patched1-dependent model directly links Hedgehog pathway dysregulation to early vertebrate eye patterning defects.
  - reference: PMID:22491411
    reference_title: "Activation of the hedgehog signaling pathway in the developing lens stimulates ectopic FoxE3 expression and disruption in fiber cell differentiation."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Hedgehog signaling is implicated in eye development, and defects in hedgehog signaling components have been shown to result in defects of the retina, iris, and lens."
    explanation: Lens-development model supports a broad role for Hedgehog dysregulation across multiple ocular structures.
  biological_processes:
  - preferred_term: eye development
    modifier: ABNORMAL
    term:
      id: GO:0001654
      label: eye development
  - preferred_term: camera-type eye development
    modifier: ABNORMAL
    term:
      id: GO:0043010
      label: camera-type eye development
  - preferred_term: lens fiber cell differentiation
    modifier: ABNORMAL
    term:
      id: GO:0070306
      label: lens fiber cell differentiation
  locations:
  - preferred_term: eye
    term:
      id: UBERON:0000970
      label: eye
  downstream:
  - target: Strabismus
    description: Developmental ocular abnormalities can manifest as abnormal ocular alignment
  - target: Congenital Cataracts
    description: Lens differentiation defects increase cataract susceptibility
  - target: Nystagmus
    description: Early visual-system developmental abnormalities can contribute to nystagmus
  - target: Coloboma
    description: Disrupted optic vesicle and fissure patterning predispose to coloboma
- name: Hedgehog-Dependent Secondary Palate Development Disruption
  biological_scale: TISSUE
  description: >-
    Hedgehog signaling interacts with other developmental pathways during palatal
    morphogenesis, and dysregulation of this program provides a mechanistic basis
    for cleft palate in Gorlin syndrome.
  evidence:
  - reference: PMID:31072004
    reference_title: "Sonic Hedgehog Signaling Is Required for Cyp26 Expression during Embryonic Development."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Using genetic and experimental approaches in the mouse, we show that during development of ontogenetically different organs, including the tail, genital tubercle, and secondary palate, Sonic hedgehog (SHH) loss-of-function causes anomalies"
    explanation: Mouse developmental data directly implicate SHH signaling in normal secondary palate morphogenesis.
  downstream:
  - target: Cleft Palate
    description: Disturbed palatal development increases the risk of clefting
- name: Hedgehog-Driven Mesenchymal Tumor Predisposition
  biological_scale: CELLULAR
  description: >-
    Gorlin syndrome includes a broader benign mesenchymal tumor predisposition,
    particularly fibromas in the heart and ovary, consistent with constitutive
    Hedgehog-pathway-driven proliferative susceptibility across multiple tissues.
  evidence:
  - reference: PMID:33860896
    reference_title: "Current recommendations for cancer surveillance in Gorlin syndrome: a report from the SIOPE host genome working group (SIOPE HGWG)."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Gorlin syndrome (MIM 109,400), a cancer predisposition syndrome related to a constitutional pathogenic variation (PV) of a gene in the Sonic Hedgehog pathway (PTCH1 or SUFU), is associated with a broad spectrum of benign and malignant tumors."
    explanation: Surveillance review supports a dedicated non-cutaneous tumor-predisposition branch within Gorlin syndrome.
  - reference: PMID:33860896
    reference_title: "Current recommendations for cancer surveillance in Gorlin syndrome: a report from the SIOPE host genome working group (SIOPE HGWG)."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Basal cell carcinomas (BCC), odontogenic keratocysts and medulloblastomas are the main tumor types encountered, but meningiomas, ovarian or cardiac fibromas and sarcomas have also been described."
    explanation: Same review explicitly places ovarian and cardiac fibromas within the Gorlin tumor spectrum.
  cell_types:
  - preferred_term: mesenchymal cell
    term:
      id: CL:0008019
      label: mesenchymal cell
  biological_processes:
  - preferred_term: cell population proliferation
    modifier: INCREASED
    term:
      id: GO:0008283
      label: cell population proliferation
  downstream:
  - target: Cardiac Fibroma
    description: Benign mesenchymal tumor susceptibility can manifest as cardiac fibroma
  - target: Ovarian Fibroma
    description: The same fibroma predisposition contributes to ovarian fibroma risk
- name: SUFU-Associated Meningioma Predisposition
  biological_scale: TISSUE
  description: >-
    SUFU germline loss-of-function genetically predisposes to meningioma
    (meningeal tissue), part of the extra-cutaneous tumor spectrum that
    distinguishes SUFU carriers from PTCH1 carriers.
  evidence:
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."
    explanation: Genotype-phenotype study shows meningioma is significantly enriched in SUFU-mutant Gorlin carriers.
  - reference: PMID:35768194
    reference_title: "Cancer risk and tumour spectrum in 172 patients with a germline SUFU pathogenic variation: a collaborative study of the SIOPE Host Genome Working Group."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients)."
    explanation: Large collaborative cohort documents 20/172 SUFU carriers with meningioma.
  downstream:
  - target: Meningioma
    description: SUFU germline LOF drives meningeal tumor development
- name: SUFU-Associated Ovarian Fibroma Predisposition
  biological_scale: TISSUE
  description: >-
    SUFU germline loss-of-function genetically predisposes to ovarian fibroma
    (ovarian stromal tissue), significantly enriched in SUFU carriers relative
    to PTCH1 carriers.
  evidence:
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."
    explanation: Ovarian fibroma is significantly enriched in SUFU-mutant Gorlin carriers.
  downstream:
  - target: Ovarian Fibroma
    description: SUFU germline LOF drives ovarian stromal fibroma development
- name: SUFU-Associated Gonadal Tumor Predisposition
  biological_scale: TISSUE
  description: >-
    SUFU germline loss-of-function genetically predisposes to adolescent and
    adult gonadal tumors (gonadal tissue), a component of the SUFU
    extra-cutaneous tumor spectrum distinct from ovarian fibroma.
  evidence:
  - reference: PMID:35768194
    reference_title: "Cancer risk and tumour spectrum in 172 patients with a germline SUFU pathogenic variation: a collaborative study of the SIOPE Host Genome Working Group."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients)."
    explanation: Large cohort documents 11/172 SUFU carriers with gonadal tumors distinct from ovarian fibroma.
  downstream:
  - target: Gonadal Tumors
    description: SUFU germline LOF drives adolescent gonadal tumor development
mechanistic_hypotheses:
- hypothesis_group_id: canonical_smo_dependent_model
  hypothesis_label: Canonical PTCH1-Loss SMO-Dependent Hedgehog Activation
  status: CANONICAL
  applies_to_subtypes:
  - PTCH1-related
  description: >-
    In the predominant PTCH1-related form, germline plus somatic (Knudson two-hit)
    loss of PTCH1 derepresses Smoothened at the primary cilium, and constitutively
    active SMO drives nuclear GLI1/GLI2 activation. Because the lesion sits upstream
    of SMO, this model predicts sensitivity to the approved SMO antagonists
    vismodegib and sonidegib and is the mechanistic basis for the BCC-, jaw-cyst-,
    and skeletal-dominant phenotype.
  evidence:
  - reference: PMID:37947611
    reference_title: "Signaling Pathways and Therapeutic Strategies in Advanced Basal Cell Carcinoma."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals."
    explanation: Establishes PTCH-loss-driven SMO/GLI activation as the canonical Hedgehog axis underlying BCC.
  - reference: PMID:22670904
    reference_title: "Inhibiting the hedgehog pathway in patients with the basal-cell nevus syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Vismodegib reduces the basal-cell carcinoma tumor burden and blocks growth of new basal-cell carcinomas in patients with the basal-cell nevus syndrome."
    explanation: Clinical responsiveness to a SMO antagonist supports the SMO-dependent (PTCH1-upstream) canonical model.
- hypothesis_group_id: sufu_smo_independent_gli_model
  hypothesis_label: SUFU-Loss SMO-Independent GLI Activation
  status: ALTERNATIVE
  applies_to_subtypes:
  - SUFU-related
  description: >-
    In SUFU-related disease the lesion lies downstream of SMO: loss of SUFU directly
    releases GLI1/GLI2 from cytoplasmic sequestration, activating the pathway
    independently of SMO. This model explains the distinct SUFU phenotype (markedly
    higher early-childhood SHH medulloblastoma, meningioma, and gonadal-tumor risk
    with fewer jaw cysts) and predicts that SMO antagonists acting upstream of the
    SUFU/GLI node will be of limited benefit in SUFU carriers.
  evidence:
  - reference: PMID:25403219
    reference_title: "Germline mutations in SUFU cause Gorlin syndrome-associated childhood medulloblastoma and redefine the risk associated with PTCH1 mutations."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We found a < 2% risk in PTCH1 mutation-positive individuals, with a risk up to 20× higher in SUFU mutation-positive individuals."
    explanation: Genotype-specific medulloblastoma risk supports a mechanistically distinct SUFU branch acting downstream of SMO.
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."
    explanation: Distinct SUFU tumor spectrum supports an SMO-independent GLI-activation model separate from the canonical PTCH1 axis.
- hypothesis_group_id: gli_bypass_resistance_model
  hypothesis_label: SMO-Inhibitor Resistance via Downstream GLI Bypass
  status: EMERGING
  description: >-
    SMO antagonists eventually fail in a substantial fraction of advanced BCCs.
    Resistance arises from acquired SMO mutations, SUFU loss, GLI2 amplification,
    and non-canonical GLI activation that all converge below the drug target,
    leaving constitutive GLI output intact. This model frames the convergent GLI
    node — not SMO — as the durable therapeutic bottleneck and motivates
    GLI-directed agents for SMO-inhibitor-resistant and SUFU-driven disease.
  notes: >-
    OpenScientist deep research (kb/hypotheses/Gorlin_Syndrome/gli_bypass_resistance_model)
    judged this hypothesis PARTIALLY SUPPORTED: GLI-convergent bypass is a real, well-documented
    resistance route (acquired SMO mutations account for ~50% of resistant sporadic BCC; aPKC-ι/λ
    non-canonical GLI activation; GLI2 amplification; and inherent SUFU-driven activation below SMO),
    and GLI-node targeting (BET/HDAC/aPKC inhibitors) overcomes resistance preclinically. Qualifications:
    (1) the model is strongest for SUFU-driven disease (BCNS2/MHIBCC) and sporadic advanced BCC, but
    weak for PTCH1-mutant Gorlin syndrome, where BCCs are uniformly suppressed by SMO inhibitors and
    secondary resistance is rare (~9% vs ~77% in sporadic advanced BCC). (2) In the one molecularly
    studied resistant Gorlin tumor, resistance arose via a GLI-independent basal-to-squamous lineage
    transition, not GLI bypass. (3) Additional GLI-independent routes exist (primary-cilia-loss RAS/MAPK
    switching; WNT-dependent persister cells). (4) The therapeutic corollary is clinically unproven —
    the only GLI-directed trial (arsenic trioxide + itraconazole, n=5) achieved ~75% GLI1 suppression
    but no meaningful tumor responses. Status EMERGING is retained pending Gorlin-specific, multi-patient
    resistance genomics.
  evidence:
  - reference: PMID:31036756
    reference_title: "Genomic testing, tumor microenvironment and targeted therapy of Hedgehog-related human cancers."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Resistance to SMO inhibitors is caused by acquired SMO mutations, SUFU deletions, GLI2 amplification, other by-passing mechanisms of GLI activation and WNT/β-catenin signaling activation."
    explanation: Documents the downstream-of-SMO bypass mechanisms that sustain GLI output despite SMO blockade.
  - reference: PMID:25759020
    reference_title: "Smoothened variants explain the majority of drug resistance in basal cell carcinoma."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Here we identify SMO mutations in 50% (22 of 44) of resistant BCCs and show that these mutations maintain Hedgehog signaling in the presence of SMO inhibitors"
    explanation: Sequencing of 44 resistant BCCs shows acquired SMO mutations sustain constitutive Hedgehog/GLI output despite SMO inhibition, the strongest quantitative support for GLI-convergent resistance.
  - reference: PMID:23446420
    reference_title: "GLI activation by atypical protein kinase C ι/λ regulates the growth of basal cell carcinomas."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "aPKC-ι/λ functions downstream of SMO to phosphorylate and activate GLI1, resulting in maximal DNA binding and transcriptional activation. Activated aPKC-ι/λ is upregulated in SMO-inhibitor-resistant tumours and targeting aPKC-ι/λ suppresses signalling and growth of resistant BCC cell lines."
    explanation: Identifies aPKC-ι/λ as a non-canonical GLI activator acting below SMO that is upregulated in resistant tumors, a direct GLI-bypass route validated in resistant BCC cell lines.
  - reference: PMID:24973920
    reference_title: "Epigenetic targeting of Hedgehog pathway transcriptional output through BET bromodomain inhibition."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Here we overcome these resistance mechanisms by modulating GLI transcription through inhibition of bromo and extra C-terminal (BET) bromodomain proteins."
    explanation: BET inhibition suppresses GLI transcription and overcomes SMO-antagonist resistance (including SUFU loss), supporting the therapeutic corollary that the convergent GLI node is druggable.
  - reference: PMID:26677003
    reference_title: "Multiple Hereditary Infundibulocystic Basal Cell Carcinoma Syndrome Associated With a Germline SUFU Mutation."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The downstream location of the SUFU gene within the sonic hedgehog pathway may explain why its loss is associated with relatively well-differentiated tumors and suggests that MHIBCC will not respond to therapeutic strategies, such as smoothened inhibitors, that target upstream components of this pathway."
    explanation: Germline plus acquired SUFU loss in MHIBCC places pathway activation below SMO, the clearest case where GLI bypass predicts inherent SMO-inhibitor resistance.
  - reference: PMID:38157930
    reference_title: "Acquisition of Drug Resistance in Basal Cell Nevus Syndrome Tumors through Basal to Squamous Cell Carcinoma Transition."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Gorlin tumors can develop resistance to SMO inhibitors through the previously described basal to squamous cell carcinoma transition."
    explanation: Qualifies the model for Gorlin syndrome specifically — the one molecularly studied resistant PTCH1-Gorlin tumor resisted via a GLI-independent basal-to-squamous lineage transition rather than GLI convergence.
phenotypes:
- category: Dermatologic
  name: Multiple Basal Cell Carcinomas
  frequency: VERY_FREQUENT
  diagnostic: true
  description: >-
    Patients typically develop multiple basal cell carcinomas, often beginning in
    childhood or adolescence. The number of tumors increases with age and UV exposure.
    BCCs may number in the hundreds over a lifetime.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "BCCs (varying clinically from flesh-colored papules to ulcerating plaques and in diameter from 1 to 10 mm) are most commonly located on the face, back and chest. The number of BBCs varies from a few to several thousand."
    explanation: Documents variable presentation and multiplicity of BCCs in Gorlin syndrome.
  - reference: PMID:40105068
    reference_title: "Basal Cell Nevus Syndrome and Sporadic Basal Cell Carcinoma: A Comparative Study of Clinicopathological Features."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The majority of basal cell carcinomas were located in the head and neck region (80.7%), with nodular BCC being the most common tumour type (47.0%)."
    explanation: Recent comparative clinicopathology study characterizes the anatomic distribution and histologic subtype profile of syndromic BCCs, showing a head-and-neck anatomic predominance (80.7%) and predominantly nodular histology (47.0%).
  phenotype_term:
    preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
- category: Dermatologic
  name: Palmar Pits
  frequency: VERY_FREQUENT
  diagnostic: true
  description: >-
    Small (1-3 mm) depressed lesions on the palms representing localized defects in
    the stratum corneum. Present in 65-87% of patients and are highly specific for
    the diagnosis.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles"
    explanation: Documents palmar manifestations as a main clinical feature of Gorlin syndrome.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0010610 | Palmar pits | Very frequent (99-80%)"
    explanation: Orphanet's HPO annotation independently classifies palmar pits as very frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Palmar pits
    term:
      id: HP:0010610
      label: Palmar pits
- category: Dermatologic
  name: Plantar Pits
  frequency: VERY_FREQUENT
  description: >-
    Pits on the soles similar to palmar pits, also representing keratinization defects
    due to Hedgehog pathway abnormalities.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0010612 | Plantar pits | Very frequent (99-80%)"
    explanation: Orphanet's HPO annotation independently classifies plantar pits as very frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Plantar pits
    term:
      id: HP:0010612
      label: Plantar pits
- category: Dermatologic
  name: Melanocytic Nevi
  frequency: VERY_FREQUENT
  description: >-
    Melanocytic nevi are included in Orphanet's very-frequent HPO phenotype
    annotations for Gorlin syndrome, expanding the dermatologic profile beyond
    basal cell carcinomas and palmoplantar pits.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0000995 | Melanocytic nevus | Very frequent (99-80%)"
    explanation: Orphanet's HPO annotation classifies melanocytic nevus as very frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Melanocytic nevi
    term:
      id: HP:0000995
      label: Melanocytic nevus
- category: Dermatologic
  name: Facial Milia
  description: >-
    Small keratin-filled facial cysts are part of the recognizable craniofacial
    and dermatologic gestalt in Gorlin syndrome.
  evidence:
  - reference: PMID:20301330
    reference_title: "Nevoid Basal Cell Carcinoma Syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Many individuals have a recognizable appearance with macrocephaly, frontal bossing, coarse facial features, and facial milia."
    explanation: GeneReviews explicitly includes facial milia among the recognizable clinical features of Gorlin syndrome.
  phenotype_term:
    preferred_term: Milia
    term:
      id: HP:0001056
      label: Milia
- category: Dental
  name: Odontogenic Keratocysts
  frequency: VERY_FREQUENT
  diagnostic: true
  description: >-
    Keratinizing cystic lesions arising in the jaw, typically appearing in the first
    decade of life. Multiple jaw cysts are highly suggestive of the diagnosis. Cysts
    have a high recurrence rate after surgical removal.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Recurrent jaw cysts occur in 90% of patients."
    explanation: Documents high frequency of odontogenic keratocysts in Gorlin syndrome.
  phenotype_term:
    preferred_term: Odontogenic keratocysts of the jaw
    term:
      id: HP:0010603
      label: Odontogenic keratocysts of the jaw
- category: Craniofacial
  name: Macrocephaly
  frequency: FREQUENT
  description: >-
    Increased head circumference is a common early-recognized developmental feature
    and may precede more specific tumor manifestations in affected children.
  evidence:
  - reference: PMID:22918513
    reference_title: "Clinical and radiological features in young individuals with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Macrocephaly was seen in 50% of affected and 8% of unaffected children/teenagers."
    explanation: Pediatric Gorlin cohort documents macrocephaly as a common early feature.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0000256 | Macrocephaly | Frequent (79-30%)"
    explanation: Orphanet's HPO annotation independently classifies macrocephaly as frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Macrocephaly
    term:
      id: HP:0000256
      label: Macrocephaly
- category: Skeletal
  name: Rib Anomalies
  frequency: FREQUENT
  description: >-
    Bifid, splayed, or fused ribs are common skeletal findings and may be detected
    incidentally on imaging.
  evidence:
  - reference: PMID:22918513
    reference_title: "Clinical and radiological features in young individuals with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "PURPOSE: Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, jaw cysts, palmar/plantar pits, spine and rib anomalies, and falx cerebri calcification."
    explanation: Pediatric cohort abstract explicitly lists rib anomalies as part of the Gorlin skeletal phenotype.
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "bifid ribs in 26%, hemivertebrae in 15%, fusion of the vertebral bodies in 10%"
    explanation: Large NIH cohort quantifies bifid ribs in 26% of affected individuals, supporting the frequent rib-anomaly designation.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0000772 | Abnormal rib morphology | Frequent (79-30%)"
    explanation: Orphanet's HPO annotation independently classifies abnormal rib morphology as frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Abnormal rib morphology
    term:
      id: HP:0000772
      label: Abnormal rib morphology
- category: Skeletal
  name: Vertebral Anomalies
  frequency: OCCASIONAL
  description: >-
    Vertebral fusion, hemivertebrae, and other spinal anomalies may occur.
  evidence:
  - reference: PMID:22918513
    reference_title: "Clinical and radiological features in young individuals with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "PURPOSE: Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, jaw cysts, palmar/plantar pits, spine and rib anomalies, and falx cerebri calcification."
    explanation: Pediatric cohort abstract explicitly lists spine anomalies as part of the Gorlin skeletal phenotype.
  phenotype_term:
    preferred_term: Abnormal vertebral morphology
    term:
      id: HP:0003468
      label: Abnormal vertebral morphology
- category: Skeletal
  name: Pectus Deformity
  frequency: OCCASIONAL
  description: >-
    Anterior chest wall deformity is part of the minor skeletal phenotype and may
    contribute to the recognizable physical appearance in affected children.
  evidence:
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."
    explanation: NIH cohort documents pectus deformity in 13% of affected individuals.
  phenotype_term:
    preferred_term: pectus deformity
    term:
      id: HP:0000766
      label: Abnormal sternum morphology
- category: Skeletal
  name: Sprengel Anomaly
  frequency: OCCASIONAL
  description: >-
    Elevated scapula (Sprengel anomaly) is an established but less common skeletal
    manifestation of Gorlin syndrome.
  evidence:
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."
    explanation: NIH cohort documents Sprengel deformity in 11% of affected individuals.
  phenotype_term:
    preferred_term: Sprengel anomaly
    term:
      id: HP:0000912
      label: Sprengel anomaly
- category: Skeletal
  name: Scoliosis
  frequency: FREQUENT
  description: >-
    Scoliosis is part of the spinal phenotype of Gorlin syndrome, accompanying the
    vertebral segmentation anomalies, and is classified as a frequent feature in
    Orphanet's HPO annotation.
  evidence:
  - reference: PMID:22918513
    reference_title: "Clinical and radiological features in young individuals with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "PURPOSE: Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, jaw cysts, palmar/plantar pits, spine and rib anomalies, and falx cerebri calcification."
    explanation: Pediatric cohort abstract lists spine anomalies, the category that encompasses scoliosis, as part of the Gorlin skeletal phenotype.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0002650 | Scoliosis | Frequent (79-30%)"
    explanation: Orphanet's HPO annotation independently classifies scoliosis as frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Scoliosis
    term:
      id: HP:0002650
      label: Scoliosis
- category: Skeletal
  name: Brachydactyly
  frequency: FREQUENT
  description: >-
    Short digits, reflecting metacarpal and phalangeal shortening (the basis of the
    classic positive metacarpal sign), broaden the hand component of the Gorlin
    skeletal phenotype and are classified as frequent in Orphanet's HPO annotation.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0001156 | Brachydactyly | Frequent (79-30%)"
    explanation: Orphanet's HPO annotation independently classifies brachydactyly as frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Brachydactyly
    term:
      id: HP:0001156
      label: Brachydactyly
- category: Intracranial
  name: Calcification of Falx Cerebri
  frequency: FREQUENT
  description: >-
    Ectopic calcification of the falx cerebri is a common radiologic finding whose
    frequency increases with age, making it useful for diagnosis and surveillance.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles, skeletal abnormalities, intracranial ectopic calcifications"
    explanation: Lists intracranial ectopic calcifications as a main clinical manifestation.
  - reference: PMID:22918513
    reference_title: "Clinical and radiological features in young individuals with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Falx calcification, the most frequent radiological feature, was present in 37% of individuals <20 and 79% of those >20 years."
    explanation: Pediatric-to-adult cohort shows age-dependent increase in falx calcification frequency.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0005462 | Calcification of falx cerebri | Frequent (79-30%)"
    explanation: Orphanet's HPO annotation independently classifies calcification of falx cerebri as frequent in Gorlin syndrome.
  phenotype_term:
    preferred_term: Calcification of falx cerebri
    term:
      id: HP:0005462
      label: Calcification of falx cerebri
- category: Oncologic
  name: Medulloblastoma
  frequency: OCCASIONAL
  description: >-
    Increased risk of early-childhood medulloblastoma that is much higher in SUFU
    carriers than in PTCH1 carriers. Gorlin-associated tumors belong to the SHH
    subgroup and are usually desmoplastic/nodular or medulloblastoma with extensive
    nodularity.
  evidence:
  - reference: PMID:25403219
    reference_title: "Germline mutations in SUFU cause Gorlin syndrome-associated childhood medulloblastoma and redefine the risk associated with PTCH1 mutations."
    supports: SUPPORT
    snippet: "Each SUFU-positive family included a single case of medulloblastoma, whereas only two (1.7%) of 115 individuals with Gorlin syndrome and a PTCH1 mutation developed medulloblastoma."
    explanation: Quantifies medulloblastoma risk by genotype, showing much higher risk in SUFU carriers.
  - reference: PMID:29186568
    reference_title: "Germline SUFU mutation carriers and medulloblastoma: clinical characteristics, cancer risk, and prognosis."
    supports: SUPPORT
    snippet: "Twenty-two patients from 17 families were identified with medulloblastoma and a germline SUFU mutation (median age at diagnosis: 16.5 mo)."
    explanation: Documents early onset of medulloblastoma in SUFU mutation carriers.
  - reference: PMID:34888241
    reference_title: "Defining the Spectrum, Treatment and Outcome of Patients With Genetically Confirmed Gorlin Syndrome From the HIT-MED Cohort."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Nine patients presented with desmoplastic medulloblastomas (DMB), 6 with medulloblastomas with extensive nodularity (MBEN) and one patient with classic medulloblastoma (CMB); all tumors affected the cerebellum, vermis or the fourth ventricle. SHH activation was present in all investigated tumors (14/16);"
    explanation: Genetically confirmed Gorlin cohort shows that associated medulloblastomas are predominantly SHH-activated infant tumors with DMB or MBEN histology.
  - reference: PMID:32747535
    reference_title: "Modeling SHH-driven medulloblastoma with patient iPS cell-derived neural stem cells."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "We found that Gorlin NES cells formed tumors in mouse cerebellum mimicking human medulloblastoma."
    explanation: iPSC model demonstrates that Gorlin patient-derived neural stem cells can form medulloblastoma-like tumors.
  phenotype_term:
    preferred_term: Medulloblastoma
    term:
      id: HP:0002885
      label: Medulloblastoma
- category: Cardiac
  name: Cardiac Fibroma
  frequency: VERY_RARE
  description: >-
    Cardiac fibromas are benign tumors that may occur in Gorlin syndrome,
    sometimes detected incidentally or presenting with arrhythmias. Reported in
    roughly 2-3% of patients, placing them in the very-rare frequency band.
  evidence:
  - reference: PMID:8326488
    reference_title: "Complications of the naevoid basal cell carcinoma syndrome: results of a population based study."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."
    explanation: Population-based study documents cardiac fibroma as a recognized but uncommon Gorlin syndrome complication.
  phenotype_term:
    preferred_term: Cardiac fibroma
    term:
      id: HP:0010617
      label: Cardiac fibroma
- category: Genitourinary
  name: Ovarian Fibroma
  frequency: OCCASIONAL
  description: >-
    Ovarian fibromas occur in approximately 17-24% of affected females and can be
    bilateral. They are enriched in SUFU mutation carriers compared to PTCH1 carriers.
    They are usually incidental findings but can become large, calcified, or cause
    ovarian torsion. Fertility is generally unaffected.
  evidence:
  - reference: PMID:8326488
    reference_title: "Complications of the naevoid basal cell carcinoma syndrome: results of a population based study."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."
    explanation: Population-based study of 84 NBCCS cases documenting ovarian calcification or fibroma in 24% of females.
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Ovarian fibromas were diagnosed by ultrasound in 9/52 (17%) at a mean age of 30 years."
    explanation: Large NIH cohort study documenting ovarian fibroma frequency in 17% of NBCCS females.
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."
    explanation: Documents significant enrichment of ovarian fibroma in SUFU versus PTCH1 mutation carriers.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0010618 | Ovarian fibroma | Occasional (29-5%)"
    explanation: Orphanet's HPO annotation independently classifies ovarian fibroma as occasional in Gorlin syndrome.
  phenotype_term:
    preferred_term: Ovarian fibroma
    term:
      id: HP:0010618
      label: Ovarian fibroma
- category: Oncologic
  name: Meningioma
  frequency: OCCASIONAL
  subtype: SUFU-related
  description: >-
    Meningioma occurs at significantly elevated frequency in SUFU mutation carriers
    (cumulative risk ~5% by age 50) compared to PTCH1 carriers (<2%). It is one of
    the three most common neoplasms in SUFU carriers alongside medulloblastoma and
    BCC. Risk is further elevated following radiation exposure. Median age at
    meningioma diagnosis is ~44 years in SUFU carriers.
  evidence:
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."
    explanation: Demonstrates that meningioma is significantly enriched in SUFU versus PTCH1 mutation carriers.
  - reference: PMID:38282294
    reference_title: "Medulloblastoma and other neoplasms in patients with heterozygous germline SUFU variants: A scoping review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "the most common were medulloblastoma (N = 59 patients), BCC (N = 21 patients), and meningioma (N = 19 patients)"
    explanation: Scoping review of 176 germline SUFU carriers confirming meningioma as one of the three most frequent neoplasms.
  - reference: PMID:35768194
    reference_title: "Cancer risk and tumour spectrum in 172 patients with a germline SUFU pathogenic variation: a collaborative study of the SIOPE Host Genome Working Group."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The cumulative risk of an MB, gonadal tumour, BCC and meningioma at age 50 years was: 13.3% (95% CI 6 to 20.1), 4.6% (95% CI 0 to 9.7), 28.5% (95% CI 13.4 to 40.9) and 5.2% (95% CI 0 to 12), respectively."
    explanation: Large collaborative cohort quantifying cumulative meningioma risk of 5.2% by age 50 in SUFU carriers.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0002858 | Meningioma | Occasional (29-5%)"
    explanation: Orphanet's HPO annotation independently classifies meningioma as occasional in Gorlin syndrome.
  phenotype_term:
    preferred_term: Meningioma
    term:
      id: HP:0002858
      label: Meningioma
- category: Genitourinary
  name: Gonadal Tumors
  frequency: OCCASIONAL
  subtype: SUFU-related
  description: >-
    Gonadal tumors occur in SUFU mutation carriers, including gonadal teratoma and
    testicular fibrosarcoma per GeneReviews. Reported in 11 of
    172 SUFU carriers in a large collaborative cohort, with a cumulative risk of ~4.6%
    by age 50. Median age at diagnosis is 14 years, making this a key surveillance
    target in adolescent SUFU carriers. Not reported in PTCH1-related Gorlin syndrome.
  evidence:
  - reference: PMID:35768194
    reference_title: "Cancer risk and tumour spectrum in 172 patients with a germline SUFU pathogenic variation: a collaborative study of the SIOPE Host Genome Working Group."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Overall, 117/172 (68%) SUFU PV carriers developed at least one tumour: medulloblastoma (MB) (86 patients), basal cell carcinoma (BCC) (25 patients), meningioma (20 patients) and gonadal tumours (11 patients)."
    explanation: Large collaborative cohort documenting gonadal tumors in 11/172 SUFU carriers, with median onset at age 14.
  phenotype_term:
    preferred_term: Gonadal neoplasm
    term:
      id: HP:0010785
      label: Gonadal neoplasm
- category: Ophthalmologic
  name: Strabismus
  frequency: FREQUENT
  description: >-
    Strabismus is the most frequent ophthalmologic finding in Gorlin syndrome,
    present in 63% of patients in a dedicated ophthalmologic study. Ocular
    involvement is systematically underrecognized in the syndrome and warrants
    routine ophthalmologic screening.
  evidence:
  - reference: PMID:31533758
    reference_title: "Ocular manifestations in Gorlin-Goltz syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "highlights strabismus (63% of the patients), epiretinal membranes (36%) and myelinated optic nerve fiber layers (36%) as the most frequent ophthalmological findings in this group of patients."
    explanation: Dedicated ophthalmologic study documenting strabismus in 63% of Gorlin-Goltz syndrome patients as the most frequent ocular finding.
  phenotype_term:
    preferred_term: Strabismus
    term:
      id: HP:0000486
      label: Strabismus
- category: Ophthalmologic
  name: Congenital Cataracts
  frequency: OCCASIONAL
  description: >-
    Congenital cataracts occur in approximately 18% of Gorlin syndrome patients
    (with combined ophthalmic abnormalities such as squint or cataract reported
    in up to 26% in a population-based study). Along with strabismus and
    hypertelorism, they represent a significant and underrecognized
    ophthalmologic feature warranting systematic screening.
  evidence:
  - reference: PMID:31533758
    reference_title: "Ocular manifestations in Gorlin-Goltz syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"
    explanation: Systematic ophthalmologic evaluation documenting congenital cataract in 18% of Gorlin-Goltz syndrome patients.
  - reference: PMID:8326488
    reference_title: "Complications of the naevoid basal cell carcinoma syndrome: results of a population based study."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."
    explanation: Population-based study documenting combined ophthalmic abnormalities (squint or cataract) in 26% of NBCCS patients; not cataract-specific.
  phenotype_term:
    preferred_term: Congenital cataracts
    term:
      id: HP:0000519
      label: Developmental cataract
- category: Ophthalmologic
  name: Nystagmus
  frequency: OCCASIONAL
  description: >-
    Nystagmus is an established but less common ocular manifestation in Gorlin
    syndrome and contributes to the broader ophthalmologic phenotype.
  evidence:
  - reference: PMID:31533758
    reference_title: "Ocular manifestations in Gorlin-Goltz syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"
    explanation: Dedicated ophthalmologic evaluation documents nystagmus in 9% of Gorlin-Goltz syndrome patients.
  phenotype_term:
    preferred_term: Nystagmus
    term:
      id: HP:0000639
      label: Nystagmus
- category: Ophthalmologic
  name: Coloboma
  frequency: OCCASIONAL
  description: >-
    Ocular coloboma is an infrequent but recurrent eye finding in Gorlin syndrome,
    supporting routine ophthalmologic surveillance.
  evidence:
  - reference: PMID:31533758
    reference_title: "Ocular manifestations in Gorlin-Goltz syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"
    explanation: Dedicated ophthalmologic evaluation documents colobomas in 9% of Gorlin-Goltz syndrome patients.
  phenotype_term:
    preferred_term: Coloboma
    term:
      id: HP:0000589
      label: Coloboma
- category: Ophthalmologic
  name: Glaucoma
  frequency: OCCASIONAL
  description: >-
    Glaucoma is a recognized but underappreciated ocular complication of Gorlin
    syndrome, classified as occasional in Orphanet's HPO annotation, and reinforces
    the rationale for systematic ophthalmologic surveillance alongside strabismus,
    cataract, and coloboma.
  evidence:
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0000501 | Glaucoma | Occasional (29-5%)"
    explanation: Orphanet's HPO annotation independently classifies glaucoma as occasional in Gorlin syndrome.
  phenotype_term:
    preferred_term: Glaucoma
    term:
      id: HP:0000501
      label: Glaucoma
- category: Craniofacial
  name: Hypertelorism
  frequency: FREQUENT
  description: >-
    Hypertelorism is present in approximately 42-45% of patients with Gorlin syndrome
    and contributes to the characteristic facial gestalt along with frontal bossing
    and coarse facial features that assists clinical recognition.
  evidence:
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."
    explanation: Large NIH cohort study documenting hypertelorism in 42% of 105 NBCCS patients.
  - reference: PMID:31533758
    reference_title: "Ocular manifestations in Gorlin-Goltz syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our study confirms the presence of the commonly cited ocular findings in the general literature regarding the syndrome [hypertelorism (45.5%), congenital cataract (18%), nystagmus (9%), colobomas (9%)]"
    explanation: Confirms hypertelorism in 45.5% of Gorlin-Goltz syndrome patients in a dedicated ophthalmologic evaluation.
  phenotype_term:
    preferred_term: Hypertelorism
    term:
      id: HP:0000316
      label: Hypertelorism
- category: Craniofacial
  name: Frontal Bossing
  frequency: OCCASIONAL
  description: >-
    Frontal bossing is present in approximately 27% of NBCCS patients and contributes
    to the characteristic facial appearance, often co-occurring with macrocephaly
    and hypertelorism.
  evidence:
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."
    explanation: Large NIH cohort documenting frontal bossing in 27% of 105 NBCCS patients.
  - reference: ORPHA:377
    reference_title: "Gorlin syndrome"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "HP:0002007 | Frontal bossing | Occasional (29-5%)"
    explanation: Orphanet's HPO annotation independently classifies frontal bossing as occasional in Gorlin syndrome.
  phenotype_term:
    preferred_term: Frontal bossing
    term:
      id: HP:0002007
      label: Frontal bossing
- category: Craniofacial
  name: Coarse Facial Features
  frequency: FREQUENT
  description: >-
    Coarsening of the facial appearance is a common part of the craniofacial
    gestalt in Gorlin syndrome and often co-occurs with macrocephaly,
    hypertelorism, and frontal bossing.
  evidence:
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "\"coarse face\" in 54%, relative macrocephaly in 50%, hypertelorism in 42%, frontal bossing in 27%, pectus deformity in 13%, and Sprengel deformity in 11%."
    explanation: Large NIH cohort documents coarse facial features in 54% of affected individuals.
  phenotype_term:
    preferred_term: Coarse facial features
    term:
      id: HP:0000280
      label: Coarse facial features
- category: Craniofacial
  name: Bridged Sella Turcica
  frequency: FREQUENT
  description: >-
    Bridging of the sella turcica is a common radiographic skull-base finding in
    Gorlin syndrome and contributes to the characteristic craniofacial imaging
    profile.
  evidence:
  - reference: PMID:9096761
    reference_title: "Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Important radiological signs included calcification of the falx cerebri in 65%, of the tentorium cerebelli in 20%, bridged sella in 68%, bifid ribs in 26%, hemivertebrae in 15%, fusion of the vertebral bodies in 10%"
    explanation: Large NIH cohort identifies bridged sella as one of the most common Gorlin radiographic signs.
  phenotype_term:
    preferred_term: Bridged sella turcica
    term:
      id: HP:0005449
      label: Bridged sella turcica
- category: Craniofacial
  name: Cleft Palate
  frequency: OCCASIONAL
  description: >-
    Cleft palate is an uncommon but recurrent craniofacial manifestation that
    broadens the developmental phenotype beyond the classic skin, jaw, and
    skeletal findings.
  evidence:
  - reference: PMID:8326488
    reference_title: "Complications of the naevoid basal cell carcinoma syndrome: results of a population based study."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Less well described complications are ovarian calcification or fibroma (24%), medulloblastoma (5%), cardiac fibroma (3%), cleft palate (5%), and ophthalmic abnormalities such as squint or cataract (26%)."
    explanation: Population-based study documents cleft palate in 5% of NBCCS cases.
  phenotype_term:
    preferred_term: Cleft palate
    term:
      id: HP:0000175
      label: Cleft palate
genetic:
- name: PTCH1
  gene_term:
    preferred_term: PTCH1
    term:
      id: hgnc:9585
      label: PTCH1
  association: Causative (Primary)
  frequency: VERY_FREQUENT
  inheritance:
  - name: Autosomal Dominant
  evidence:
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    snippet: "A total of 126 patients had a heterozygous pathogenic variant, 9 had SUFU pathogenic variants and 46 had no identified mutation."
    explanation: Supports predominance of non-SUFU pathogenic variants in this cohort, but the snippet does not explicitly name PTCH1 in the quoted text.
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    snippet: "Patients with a missense variant in PTCH1 were diagnosed later (p=0.03) and were less likely to develop at least 10 BCCs and jaw cysts than those with other pathogenic PTCH1 variants (p=0.03)."
    explanation: Demonstrates genotype-phenotype correlation with milder disease in missense variant carriers.
  - reference: CGGV:assertion_2a3f55f5-e39b-4571-a41f-e46ddb8e298d-2018-06-04T170000.000Z
    reference_title: "PTCH1 / nevoid basal cell carcinoma syndrome (Definitive)"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "PTCH1 | HGNC:9585 | nevoid basal cell carcinoma syndrome | MONDO:0007187 | AD | Definitive"
    explanation: ClinGen classifies the PTCH1-nevoid basal cell carcinoma syndrome relationship as definitive with autosomal dominant inheritance.
  notes: >-
    PTCH1 mutations account for approximately 85-95% of Gorlin syndrome cases. The
    gene is located on chromosome 9q22.3. Over 300 different pathogenic variants have
    been reported, including frameshift, nonsense, splice site, and missense mutations.
    Large deletions may occur. Penetrance is high but expressivity is variable.
- name: PTCH2
  gene_term:
    preferred_term: PTCH2
    term:
      id: hgnc:9586
      label: PTCH2
  association: Limited ClinGen gene-disease validity assertion
  inheritance:
  - name: Autosomal Dominant
  evidence:
  - reference: CGGV:assertion_d189ca00-ba80-49af-9b2e-8523c8d29a44-2018-10-12T213908.660Z
    reference_title: "PTCH2 / nevoid basal cell carcinoma syndrome (Limited)"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "PTCH2 | HGNC:9586 | nevoid basal cell carcinoma syndrome | MONDO:0007187 | AD | Limited"
    explanation: ClinGen records a limited autosomal dominant PTCH2-nevoid basal cell carcinoma syndrome assertion for the same MONDO disease concept, so it is included as lower-confidence structured disease-gene evidence.
  notes: >-
    ClinGen classifies PTCH2 for nevoid basal cell carcinoma syndrome as Limited,
    so this entry records it separately from the primary PTCH1 and SUFU causes.
- name: SUFU
  gene_term:
    preferred_term: SUFU
    term:
      id: hgnc:16466
      label: SUFU
  association: Causative (Alternative)
  frequency: OCCASIONAL
  inheritance:
  - name: Autosomal Dominant
  evidence:
  - reference: PMID:25403219
    reference_title: "Germline mutations in SUFU cause Gorlin syndrome-associated childhood medulloblastoma and redefine the risk associated with PTCH1 mutations."
    supports: SUPPORT
    snippet: "We demonstrate convincing evidence that SUFU mutations can cause classical Gorlin syndrome."
    explanation: Establishes SUFU as a causative gene for Gorlin syndrome.
  - reference: PMID:28596197
    reference_title: "First evidence of genotype-phenotype correlations in Gorlin syndrome."
    supports: SUPPORT
    snippet: "Patients with SUFU pathogenic variants were significantly more likely than those with PTCH1 pathogenic variants to develop a medulloblastoma (p=0.009), a meningioma (p=0.02) or an ovarian fibroma (p=0.015), but were less likely to develop a jaw cyst (p=0.0004)."
    explanation: Documents distinct phenotypic spectrum in SUFU versus PTCH1 mutation carriers.
  notes: >-
    SUFU mutations account for approximately 5% of Gorlin syndrome cases. SUFU mutations
    are associated with a markedly higher risk of medulloblastoma (up to 20-fold)
    and
    meningioma compared to PTCH1 mutations, but lower rates of jaw cysts.
environmental:
- name: Ultraviolet Radiation
  exposure_term:
    preferred_term: exposure to ultraviolet radiation
    term:
      id: ECTO:0000006
      label: exposure to ultraviolet radiation
  influences_mechanisms:
  - target: PTCH1 Somatic Second-Hit Loss
    environmental_effect: TRIGGERS
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    description: >-
      The germline first hit is inherited and unavoidable; ultraviolet light
      supplies the somatic second hit in sun-exposed skin, via DNA
      photoproducts and their mis-repair. That is why tumour burden tracks sun
      exposure in an otherwise fixed genotype.
    evidence:
    - reference: PMID:12007715
      reference_title: "Mutations of the p53 and PTCH gene in basal cell carcinomas: UV mutation signature and strand bias."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "p53 and PTCH mutations were detected at a frequency of 33 and 40%, respectively, and the mutations were predominantly UV-signature transition, C-->T transitions at dipyrimidine sites and CC-->TT tandem mutations."
      explanation: >-
        PTCH mutations recovered from basal cell carcinomas carry the C to T and
        CC to TT changes at dipyrimidine sites that only ultraviolet light
        produces, so ultraviolet exposure is the mutagen inactivating the gene.
        The series is sporadic disease; the inference here is that the same
        mutagenic route supplies the somatic hit in germline carriers.
  description: >-
    UV exposure accelerates development and increases the number of basal cell carcinomas
    in affected individuals. Sun protection is a critical component of management.
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Patients with NBCCS should strictly avoid an excessive sun exposure."
    explanation: Clinical recommendation to avoid sun exposure to prevent BCC development.
- name: Ionizing Radiation
  exposure_term:
    preferred_term: exposure to ionizing radiation
    term:
      id: ECTO:7000047
      label: exposure to ionizing radiation
  influences_mechanisms:
  - target: PTCH1 Somatic Second-Hit Loss
    environmental_effect: TRIGGERS
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    description: >-
      Therapeutic irradiation supplies the same somatic second hit through DNA
      double-strand breaks, which is why radiotherapy in these patients
      produces basal cell carcinomas within the treated field.
    evidence:
    - reference: PMID:6837723
      reference_title: "Cultured diploid fibroblasts from patients with the nevoid basal cell carcinoma syndrome are hypersensitive to killing by ionizing radiation."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Clinical follow-up of these patients, treated with radiotherapy, revealed a predisposition to radiogenic basal cell carcinomas with an unusually short latent period of 6 months to 3 years."
      explanation: >-
        Documents a predisposition to radiogenic basal cell carcinomas in
        irradiated patients, tumours arising in the field where radiation
        delivered the somatic damage.
  description: >-
    Patients with Gorlin syndrome are exquisitely sensitive to ionizing radiation,
    which
    can induce numerous BCCs in the radiation field. Radiotherapy should be avoided
    when
    possible, including for medulloblastoma treatment.
  evidence:
  - reference: PMID:6837723
    reference_title: "Cultured diploid fibroblasts from patients with the nevoid basal cell carcinoma syndrome are hypersensitive to killing by ionizing radiation."
    supports: SUPPORT
    snippet: "Clinical follow-up of these patients, treated with radiotherapy, revealed a predisposition to radiogenic basal cell carcinomas with an unusually short latent period of 6 months to 3 years."
    explanation: Documents radiation-induced BCCs in NBCCS patients with abnormally short latency.
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Radiotherapy should be avoided."
    explanation: Clinical recommendation to avoid radiotherapy in NBCCS patients due to radiation sensitivity.
treatments:
- name: Surgical Excision
  description: >-
    Surgical removal of basal cell carcinomas is the primary treatment. Mohs micrographic
    surgery may be preferred for facial lesions to preserve tissue. Given the multiplicity
    of tumors, repeated surgeries are often necessary.
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  - preferred_term: Odontogenic keratocysts of the jaw
    term:
      id: HP:0010603
      label: Odontogenic keratocysts of the jaw
  treatment_term:
    preferred_term: Excision
    term:
      id: NCIT:C15232
      label: Excision
- name: Vismodegib
  description: >-
    Hedgehog pathway inhibitor approved for locally advanced BCC. Can reduce tumor
    burden
    in patients with multiple BCCs, but side effects (muscle spasms, dysgeusia, alopecia)
    limit long-term use. Tumors may regrow after discontinuation.
  therapeutic_modality: SMALL_MOLECULE
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  target_mechanisms:
  - target: SMO Constitutive Activation
    treatment_effect: INHIBITS
    description: >-
      Vismodegib binds SMO and restores its inhibited conformation, blocking constitutive
      Hedgehog pathway output in PTCH1-driven Gorlin BCCs. Because SUFU-mutant disease
      constitutively activates GLI downstream of SMO, SMO inhibitors have limited efficacy
      in SUFU-driven tumors; resistance can also emerge via SMO resistance mutations or
      downstream GLI amplification that bypasses this node.
  evidence:
  - reference: PMID:22670904
    reference_title: "Inhibiting the hedgehog pathway in patients with the basal-cell nevus syndrome."
    supports: SUPPORT
    snippet: "Vismodegib reduces the basal-cell carcinoma tumor burden and blocks growth of new basal-cell carcinomas in patients with the basal-cell nevus syndrome."
    explanation: Randomized controlled trial demonstrating efficacy of vismodegib in reducing BCC burden in Gorlin syndrome.
  - reference: PMID:22670904
    reference_title: "Inhibiting the hedgehog pathway in patients with the basal-cell nevus syndrome."
    supports: SUPPORT
    snippet: "The adverse events associated with treatment led to discontinuation in over half of treated patients."
    explanation: Documents significant tolerability issues with vismodegib leading to high discontinuation rates.
  treatment_term:
    preferred_term: targeted therapy
    term:
      id: NCIT:C93352
      label: Targeted Therapy
    therapeutic_agent:
    - preferred_term: vismodegib
      term:
        id: CHEBI:66903
        label: vismodegib
- name: Sonidegib
  description: >-
    Alternative SMO inhibitor for locally advanced BCC. Similar mechanism and side
    effect profile to vismodegib.
  therapeutic_modality: SMALL_MOLECULE
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  target_mechanisms:
  - target: SMO Constitutive Activation
    treatment_effect: INHIBITS
    description: >-
      Sonidegib likewise binds SMO, blocking constitutive Hedgehog signaling in PTCH1-driven
      Gorlin BCCs with a similar mechanism and resistance profile to vismodegib.
  treatment_term:
    preferred_term: targeted therapy
    term:
      id: NCIT:C93352
      label: Targeted Therapy
    therapeutic_agent:
    - preferred_term: sonidegib
      term:
        id: CHEBI:90863
        label: sonidegib
- name: Topical Patidegib (Investigational)
  description: >-
    Patidegib is a cyclopamine-derived SMO/Hedgehog inhibitor formulated as a
    topical gel to deliver local anti-BCC activity while keeping systemic drug
    levels low, aiming to avoid the muscle spasms, dysgeusia, and alopecia that
    drive discontinuation of oral Hedgehog inhibitors. A randomized double-blind
    phase IIA trial in Gorlin syndrome suggested reduced numbers of new
    surgically eligible BCCs with minimal adverse effects; it remains
    investigational and not yet approved.
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  target_mechanisms:
  - target: SMO Constitutive Activation
    treatment_effect: INHIBITS
    description: >-
      Patidegib binds SMO and dampens constitutive Hedgehog output locally in the
      skin; topical delivery is intended to suppress field BCC formation without
      the systemic exposure that limits oral SMO antagonists.
  evidence:
  - reference: PMID:39545486
    reference_title: "Topical application of the Hedgehog inhibitor patidegib in patients with Gorlin syndrome: a phase II trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Post hoc analyses suggested that patidegib topical gel reduced the number of new, surgically eligible BCCs and the level of HH signalling, with minimal adverse effects."
    explanation: Phase IIA randomized trial in Gorlin syndrome supports topical patidegib as an emerging field therapy that reduces new BCCs with minimal systemic toxicity.
  - reference: PMID:39545486
    reference_title: "Topical application of the Hedgehog inhibitor patidegib in patients with Gorlin syndrome: a phase II trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "we developed a gel containing a small cyclopamine-derived molecule that can be applied topically in expectation that this mode of delivery can reduce the burden of BCCs without producing the systemic adverse effects that cause patients to stop oral HHi treatment."
    explanation: Documents the rationale for topical delivery to decouple local Hedgehog blockade from the systemic toxicity of oral SMO inhibitors.
  treatment_term:
    preferred_term: topical pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: patidegib
      term:
        id: NCIT:C80063
        label: Patidegib
- name: Laser Ablation Therapy
  description: >-
    Laser ablation and photodynamic therapy may be useful for treating multiple
    superficial BCCs with acceptable cosmetic outcomes. Less effective for nodular
    or aggressive subtypes.
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Surgery for BBCs is indicated when the number of lesions is limited; other treatments include laser ablation, photodynamic therapy and topical chemotherapy."
    explanation: Supports laser-based local therapy as a lesion-directed option for multiple superficial BCCs in Gorlin syndrome.
  treatment_term:
    preferred_term: laser ablation therapy
    term:
      id: NCIT:C111241
      label: Laser Ablation
- name: Topical Therapy
  description: >-
    Topical imiquimod or 5-fluorouracil may be used for superficial BCCs to reduce
    surgical burden.
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Surgery for BBCs is indicated when the number of lesions is limited; other treatments include laser ablation, photodynamic therapy and topical chemotherapy."
    explanation: Supports topical chemotherapy as a non-surgical option for superficial BCCs in Gorlin syndrome.
  treatment_term:
    preferred_term: topical pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
- name: Sun Avoidance
  description: >-
    Rigorous sun protection with sunscreen, protective clothing, and sunlight avoidance
    is essential to reduce the development of new BCCs.
  target_phenotypes:
  - preferred_term: Basal cell carcinoma
    term:
      id: HP:0002671
      label: Basal cell carcinoma
  evidence:
  - reference: PMID:19032739
    reference_title: "Nevoid basal cell carcinoma syndrome (Gorlin syndrome)."
    supports: SUPPORT
    snippet: "Patients with NBCCS should strictly avoid an excessive sun exposure."
    explanation: Supports UV avoidance as a preventive intervention to reduce new BCC formation in Gorlin syndrome.
  treatment_term:
    preferred_term: sunlight avoidance
    term:
      id: NCIT:C15900
      label: Lifestyle Therapy
- name: Genetic Counseling
  description: >-
    Given autosomal dominant inheritance and 50% recurrence risk, genetic counseling
    is recommended for affected individuals and at-risk family members.
  treatment_term:
    preferred_term: Genetic Counseling
    term:
      id: NCIT:C15240
      label: Genetic Counseling
diagnosis:
- name: Clinical Criteria
  description: >-
    Diagnosis is based on clinical criteria. Major criteria include multiple (>2)
    BCCs
    or one BCC before age 20, odontogenic keratocysts, palmar/plantar pits, calcification
    of falx cerebri, and first-degree relative with NBCCS. Minor criteria include
    medulloblastoma, ovarian fibroma, macrocephaly, and various skeletal anomalies.
    Two major criteria or one major plus two minor criteria suggest the diagnosis.
- name: Genetic Testing
  description: >-
    Molecular testing for PTCH1 and SUFU mutations can confirm the diagnosis and is
    particularly useful for at-risk family members and in atypical presentations.
discussions:
- discussion_id: gap_gli_directed_therapy_resistance
  prompt: >-
    Can GLI-directed agents control SMO-inhibitor-resistant or SUFU-driven Gorlin
    tumors, given that the durable therapeutic bottleneck lies at the convergent
    GLI node rather than at SMO?
  kind: KNOWLEDGE_GAP
  status: OPEN
  attaches_to:
  - pathophysiology#GLI Transcription Factor Activation
  - pathophysiology#SMO Constitutive Activation
  rationale: >-
    The only approved targeted therapies for Gorlin-associated BCC (vismodegib,
    sonidegib) act at SMO and therefore have limited efficacy in SUFU-related
    disease, which activates GLI downstream of SMO, and in tumors that acquire
    resistance via SMO mutation, SUFU loss, or GLI2 amplification. No GLI-directed
    drug is approved, leaving SUFU carriers and SMO-inhibitor-resistant patients
    without a pathway-targeted option. Resolving whether GLI antagonists are
    effective and tolerable would close a major translational gap shared by the
    sufu_smo_independent_gli_model and gli_bypass_resistance_model hypotheses.
  proposed_experiments:
  - experiment_id: exp_gli_antagonist_sufu_resistant_models
    name: GLI-directed therapy in SUFU-null and SMO-inhibitor-resistant Gorlin models
    description: >-
      Test GLI-DNA-interaction inhibitors and GLI2 destabilizers against
      patient-derived SUFU-mutant medulloblastoma neural stem cells, PTCH1-mutant
      BCC organoids, and isogenic vismodegib-resistant BCC lines bearing SMO
      mutations or GLI2 amplification, comparing GLI output, proliferation, and
      tumor growth with SMO-antagonist arms.
    experiment_type:
      preferred_term: controlled perturbation experiment
    decision_criterion: >-
      GLI-directed agents reduce GLI target-gene expression and tumor growth in
      SUFU-null and SMO-inhibitor-resistant models where SMO antagonists fail.
    would_support:
    - mechanistic_hypotheses#gli_bypass_resistance_model
    - mechanistic_hypotheses#sufu_smo_independent_gli_model
    would_refute:
    - mechanistic_hypotheses#canonical_smo_dependent_model
  evidence:
  - reference: PMID:31036756
    reference_title: "Genomic testing, tumor microenvironment and targeted therapy of Hedgehog-related human cancers."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "GLI-DNA-interaction inhibitors (glabrescione B and GANT61), GLI2 destabilizers (arsenic trioxide and pirfenidone) and a GLI-deacetylation inhibitor (4SC-202) were shown to block GLI-dependent transcription and tumorigenesis in preclinical studies."
    explanation: Preclinical GLI-directed agents exist but none are clinically validated for Gorlin disease, defining the translational gap.
- discussion_id: gap_genotype_tissue_specificity
  prompt: >-
    Why does PTCH1 loss preferentially drive BCC, jaw cysts, and skeletal anomalies
    while SUFU loss preferentially drives early-childhood medulloblastoma,
    meningioma, and gonadal tumors, despite both converging on GLI activation?
  kind: KNOWLEDGE_GAP
  status: OPEN
  attaches_to:
  - pathophysiology#SUFU Germline Mutations
  - pathophysiology#SHH-Responsive Cerebellar Progenitor Expansion
  - pathophysiology#GLI Transcription Factor Activation
  rationale: >-
    The strong, reproducible genotype-phenotype divergence between PTCH1 and SUFU
    carriers implies that the two lesions are not simply interchangeable inputs to
    a single GLI output. Tissue-specific differences in ciliary signaling, SUFU's
    GLI-stabilizing versus GLI-repressing roles, dosage thresholds, and the timing
    of second-hit inactivation in cerebellar granule precursors versus epidermal
    basal cells are all candidate explanations, but the mechanistic basis is
    unresolved. Closing this gap would refine surveillance (which tissues to watch
    by genotype) and clarify why SMO-level versus GLI-level lesions yield distinct
    tumor spectra.
  proposed_experiments:
  - experiment_id: exp_genotype_lineage_resolved_hh_output
    name: Lineage-resolved Hedgehog output in isogenic PTCH1-null versus SUFU-null cells
    description: >-
      Generate isogenic PTCH1-null and SUFU-null human iPSC lines, differentiate
      into cerebellar granule-cell precursors, epidermal basal keratinocytes, and
      meningeal/gonadal-relevant lineages, and quantify ciliary GLI processing,
      GLI activator/repressor balance, and proliferative response per lineage.
    experiment_type:
      preferred_term: comparative isogenic differentiation assay
    decision_criterion: >-
      SUFU-null cells show disproportionately higher GLI-activator output in
      cerebellar precursors than PTCH1-null cells, while PTCH1-null cells show
      stronger output in basal keratinocytes.
    would_support:
    - mechanistic_hypotheses#sufu_smo_independent_gli_model
- discussion_id: gap_durable_low_toxicity_chemoprevention
  prompt: >-
    Is there a durable, low-toxicity field therapy that prevents new BCC formation
    in Gorlin syndrome without the systemic adverse effects and rebound regrowth
    that limit oral Hedgehog inhibitors?
  kind: KNOWLEDGE_GAP
  status: OPEN
  attaches_to:
  - pathophysiology#SMO Constitutive Activation
  - phenotypes#Multiple Basal Cell Carcinomas
  rationale: >-
    Patients accumulate hundreds of lifelong BCCs, yet oral SMO antagonists cause
    muscle spasms, dysgeusia, and alopecia that drive discontinuation in over half
    of patients, and tumors regrow after stopping. Topical patidegib is a promising
    field approach but remains investigational on small phase II data, and recent
    consensus guidelines note that Gorlin-specific evidence is sparse. Whether a
    chronically tolerable preventive therapy exists is an open clinical gap.
  proposed_experiments:
  - experiment_id: exp_topical_hhi_chemoprevention_rct
    name: Adequately powered trial of topical Hedgehog-inhibitor field chemoprevention
    description: >-
      Conduct a larger randomized controlled trial of topical patidegib (or a
      next-generation topical SMO/GLI inhibitor) versus vehicle in Gorlin syndrome,
      with new-BCC incidence, systemic drug exposure, and quality-of-life endpoints
      over multi-year follow-up.
    experiment_type:
      preferred_term: randomized controlled trial
    decision_criterion: >-
      Topical therapy significantly reduces new-BCC incidence versus vehicle with
      low systemic exposure and acceptable tolerability sustained over years.
  evidence:
  - reference: PMID:39545486
    reference_title: "Topical application of the Hedgehog inhibitor patidegib in patients with Gorlin syndrome: a phase II trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patidegib topical gel warrants further clinical development."
    explanation: The trial authors themselves flag that topical Hedgehog-inhibitor chemoprevention is promising but not yet established, defining the gap.
  - reference: PMID:41396574
    reference_title: "Clinical practice guidelines for the management of basal cell carcinoma in Gorlin syndrome."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Given the scarcity of GS-specific data, expert consensus informed several recommendations, highlighting the need for ongoing research to strengthen the evidence base."
    explanation: 2025 consensus guidelines explicitly identify the sparse Gorlin-specific evidence base as an unmet research need.
datasets:
notes: >-
  Gorlin syndrome illustrates how germline loss of negative regulators of
  Hedgehog signaling produces both developmental anomalies and genotype-specific
  tumor susceptibility. PTCH1-related disease is dominated by BCCs, jaw cysts,
  and skeletal findings, whereas SUFU-related disease shifts risk toward
  early-childhood SHH medulloblastoma and later meningioma.
references:
- reference: PMID:20301330
  title: "Nevoid Basal Cell Carcinoma Syndrome"
  tags:
  - GeneReviews
- reference: DOI:10.1002/ajmg.a.63788
  title: 'Germline <scp><i>PTCH1</i></scp>: <scp>c.361_362insAlu</scp> alteration identified by comprehensive exome and <scp>RNA</scp> sequencing in a patient with <scp>Gorlin</scp> syndrome'
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: Gorlin syndrome can be caused by pathogenic/likely pathogenic (P/LP) variants in the tumor suppressor gene PTCH1 (9q22.1‐q31), which encodes the receptor for the sonic hedgehog (SHH) ligand.
    supporting_text: Gorlin syndrome can be caused by pathogenic/likely pathogenic (P/LP) variants in the tumor suppressor gene PTCH1 (9q22.1‐q31), which encodes the receptor for the sonic hedgehog (SHH) ligand.
    evidence:
    - reference: DOI:10.1002/ajmg.a.63788
      reference_title: 'Germline <scp><i>PTCH1</i></scp>: <scp>c.361_362insAlu</scp> alteration identified by comprehensive exome and <scp>RNA</scp> sequencing in a patient with <scp>Gorlin</scp> syndrome'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Gorlin syndrome can be caused by pathogenic/likely pathogenic (P/LP) variants in the tumor suppressor gene PTCH1 (9q22.1‐q31), which encodes the receptor for the sonic hedgehog (SHH) ligand.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.
- reference: DOI:10.1158/1078-0432.ccr-23-4033
  title: Update on Cancer Predisposition Syndromes and Surveillance Guidelines for Childhood Brain Tumors
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood.
    supporting_text: Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood.
    evidence:
    - reference: DOI:10.1158/1078-0432.ccr-23-4033
      reference_title: Update on Cancer Predisposition Syndromes and Surveillance Guidelines for Childhood Brain Tumors
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.
- reference: DOI:10.1186/s12885-024-13101-z
  title: Interim analysis of the multinational, post-authorization safety study (NISSO) to assess the long-term safety of sonidegib in patients with locally advanced basal cell carcinoma
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: Following the pivotal phase II trial BOLT, the Hedgehog (Hh) inhibitor sonidegib was approved in the EU to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiotherapy.
    supporting_text: Following the pivotal phase II trial BOLT, the Hedgehog (Hh) inhibitor sonidegib was approved in the EU to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiotherapy.
    evidence:
    - reference: DOI:10.1186/s12885-024-13101-z
      reference_title: Interim analysis of the multinational, post-authorization safety study (NISSO) to assess the long-term safety of sonidegib in patients with locally advanced basal cell carcinoma
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Following the pivotal phase II trial BOLT, the Hedgehog (Hh) inhibitor sonidegib was approved in the EU to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiotherapy.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.
- reference: DOI:10.1186/s13000-023-01406-9
  title: 'Bilateral ovarian fibromas as the sole manifestation of Gorlin syndrome in a 22-year-old woman: a case report and literature review'
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: 'Bilateral ovarian fibromas as the sole manifestation of Gorlin syndrome in a 22-year-old woman: a case report and literature review'
    supporting_text: Nevoid basal cell carcinoma syndrome (NBCCS, Gorlin syndrome) is a rare autosomal dominantly inherited disorder that is characterized by multisystem disorder such as basal cell carcinomas, keratocystic odontogenic tumors and skeletal abnormalities.
    evidence:
    - reference: DOI:10.1186/s13000-023-01406-9
      reference_title: 'Bilateral ovarian fibromas as the sole manifestation of Gorlin syndrome in a 22-year-old woman: a case report and literature review'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Nevoid basal cell carcinoma syndrome (NBCCS, Gorlin syndrome) is a rare autosomal dominantly inherited disorder that is characterized by multisystem disorder such as basal cell carcinomas, keratocystic odontogenic tumors and skeletal abnormalities.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.
- reference: DOI:10.3390/cancers16122166
  title: 'Gorlin Syndrome-Associated Basal Cell Carcinomas Treated with Vismodegib or Sonidegib: A Retrospective Study'
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome (GS), is a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway.
    supporting_text: Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome (GS), is a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway.
    evidence:
    - reference: DOI:10.3390/cancers16122166
      reference_title: 'Gorlin Syndrome-Associated Basal Cell Carcinomas Treated with Vismodegib or Sonidegib: A Retrospective Study'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome (GS), is a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.
- reference: DOI:10.3390/curroncol30100661
  title: 'Sustained Suppression of Gorlin Syndrome-Associated Basal Cell Carcinomas with Vismodegib or Sonidegib: A Case Series'
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: Nevoid basal-cell carcinoma syndrome (Gorlin syndrome) is characterized by numerous cutaneous basal cell carcinomas mediated by mutations in the hedgehog pathway.
    supporting_text: Nevoid basal-cell carcinoma syndrome (Gorlin syndrome) is characterized by numerous cutaneous basal cell carcinomas mediated by mutations in the hedgehog pathway.
    evidence:
    - reference: DOI:10.3390/curroncol30100661
      reference_title: 'Sustained Suppression of Gorlin Syndrome-Associated Basal Cell Carcinomas with Vismodegib or Sonidegib: A Case Series'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Nevoid basal-cell carcinoma syndrome (Gorlin syndrome) is characterized by numerous cutaneous basal cell carcinomas mediated by mutations in the hedgehog pathway.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.
- reference: DOI:10.3390/ijms241612903
  title: Hedgehog-Related Mutation Causes Bone Malformations with or without Hereditary Gene Mutations
  found_in:
  - Gorlin_Syndrome-deep-research-falcon.md
  findings:
  - statement: The hedgehog (Hh) family consists of numerous signaling mediators that play important roles at various stages of development.
    supporting_text: The hedgehog (Hh) family consists of numerous signaling mediators that play important roles at various stages of development.
    evidence:
    - reference: DOI:10.3390/ijms241612903
      reference_title: Hedgehog-Related Mutation Causes Bone Malformations with or without Hereditary Gene Mutations
      supports: SUPPORT
      evidence_source: OTHER
      snippet: The hedgehog (Hh) family consists of numerous signaling mediators that play important roles at various stages of development.
      explanation: Deep research cited this publication as relevant literature for Gorlin Syndrome.

📚

References & Deep Research

References

8

PMID:20301330

Nevoid Basal Cell Carcinoma Syndrome

No top-level findings curated for this source.

DOI:10.1002/ajmg.a.63788

Germline <scp><i>PTCH1</i></scp>: <scp>c.361_362insAlu</scp> alteration identified by comprehensive exome and <scp>RNA</scp> sequencing in a patient with <scp>Gorlin</scp> syndrome

1 finding

Gorlin syndrome can be caused by pathogenic/likely pathogenic (P/LP) variants in the tumor suppressor gene PTCH1 (9q22.1‐q31), which encodes the receptor for the sonic hedgehog (SHH) ligand.

"Gorlin syndrome can be caused by pathogenic/likely pathogenic (P/LP) variants in the tumor suppressor gene PTCH1 (9q22.1‐q31), which encodes the receptor for the sonic hedgehog (SHH) ligand."

Show evidence (1 reference)

DOI:10.1002/ajmg.a.63788 SUPPORT Human Clinical

"Gorlin syndrome can be caused by pathogenic/likely pathogenic (P/LP) variants in the tumor suppressor gene PTCH1 (9q22.1‐q31), which encodes the receptor for the sonic hedgehog (SHH) ligand."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

DOI:10.1158/1078-0432.ccr-23-4033

Update on Cancer Predisposition Syndromes and Surveillance Guidelines for Childhood Brain Tumors

1 finding

Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood.

"Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood."

Show evidence (1 reference)

DOI:10.1158/1078-0432.ccr-23-4033 SUPPORT Human Clinical

"Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

DOI:10.1186/s12885-024-13101-z

Interim analysis of the multinational, post-authorization safety study (NISSO) to assess the long-term safety of sonidegib in patients with locally advanced basal cell carcinoma

1 finding

Following the pivotal phase II trial BOLT, the Hedgehog (Hh) inhibitor sonidegib was approved in the EU to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiotherapy.

"Following the pivotal phase II trial BOLT, the Hedgehog (Hh) inhibitor sonidegib was approved in the EU to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiotherapy."

Show evidence (1 reference)

DOI:10.1186/s12885-024-13101-z SUPPORT Human Clinical

"Following the pivotal phase II trial BOLT, the Hedgehog (Hh) inhibitor sonidegib was approved in the EU to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiotherapy."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

DOI:10.1186/s13000-023-01406-9

Bilateral ovarian fibromas as the sole manifestation of Gorlin syndrome in a 22-year-old woman: a case report and literature review

1 finding

Bilateral ovarian fibromas as the sole manifestation of Gorlin syndrome in a 22-year-old woman: a case report and literature review

"Nevoid basal cell carcinoma syndrome (NBCCS, Gorlin syndrome) is a rare autosomal dominantly inherited disorder that is characterized by multisystem disorder such as basal cell carcinomas, keratocystic odontogenic tumors and skeletal abnormalities."

Show evidence (1 reference)

DOI:10.1186/s13000-023-01406-9 SUPPORT Human Clinical

"Nevoid basal cell carcinoma syndrome (NBCCS, Gorlin syndrome) is a rare autosomal dominantly inherited disorder that is characterized by multisystem disorder such as basal cell carcinomas, keratocystic odontogenic tumors and skeletal abnormalities."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

DOI:10.3390/cancers16122166

Gorlin Syndrome-Associated Basal Cell Carcinomas Treated with Vismodegib or Sonidegib: A Retrospective Study

1 finding

Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome (GS), is a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway.

"Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome (GS), is a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway."

Show evidence (1 reference)

DOI:10.3390/cancers16122166 SUPPORT Human Clinical

"Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome (GS), is a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

DOI:10.3390/curroncol30100661

Sustained Suppression of Gorlin Syndrome-Associated Basal Cell Carcinomas with Vismodegib or Sonidegib: A Case Series

1 finding

Nevoid basal-cell carcinoma syndrome (Gorlin syndrome) is characterized by numerous cutaneous basal cell carcinomas mediated by mutations in the hedgehog pathway.

"Nevoid basal-cell carcinoma syndrome (Gorlin syndrome) is characterized by numerous cutaneous basal cell carcinomas mediated by mutations in the hedgehog pathway."

Show evidence (1 reference)

DOI:10.3390/curroncol30100661 SUPPORT Human Clinical

"Nevoid basal-cell carcinoma syndrome (Gorlin syndrome) is characterized by numerous cutaneous basal cell carcinomas mediated by mutations in the hedgehog pathway."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

DOI:10.3390/ijms241612903

Hedgehog-Related Mutation Causes Bone Malformations with or without Hereditary Gene Mutations

1 finding

The hedgehog (Hh) family consists of numerous signaling mediators that play important roles at various stages of development.

"The hedgehog (Hh) family consists of numerous signaling mediators that play important roles at various stages of development."

Show evidence (1 reference)

DOI:10.3390/ijms241612903 SUPPORT Other

"The hedgehog (Hh) family consists of numerous signaling mediators that play important roles at various stages of development."

Deep research cited this publication as relevant literature for Gorlin Syndrome.

Deep Research

1

Falcon ▸

Gorlin Syndrome (Nevoid Basal Cell Carcinoma Syndrome; NBCCS) — Disease Characteristics Research Report

Edison Scientific Literature 24 citations 2026-05-08T20:11:39.859165

Gorlin Syndrome (Nevoid Basal Cell Carcinoma Syndrome; NBCCS) — Disease Characteristics Research Report

Target Disease

Disease name: Gorlin syndrome
Category: Mendelian (autosomal dominant tumor predisposition)
MONDO ID: Not available in the retrieved source set (explicit MONDO identifier not found).

Evidence base and scope

This report synthesizes the retrieved 2023–2024 primary/review literature and ClinicalTrials.gov records. Several authoritative guideline-level recommendations come from an AACR Cancer Predisposition Working Group publication in Clinical Cancer Research (Apr 2024) and real-world safety data from the NISSO post-authorization study in BMC Cancer (Nov 2024). Where specific controlled vocabulary identifiers (e.g., ICD-10/11, Orphanet, MONDO) or PMIDs were not present in the retrieved texts, this is explicitly noted.

Structured summary table

The following table is optimized for disease knowledge-base ingestion.

Category	Key facts	Best supporting citations
Identifiers/Synonyms	Gorlin syndrome is also called nevoid basal cell carcinoma syndrome (NBCCS), Gorlin-Goltz syndrome, basal cell nevus syndrome (BCNS), multiple basal cell carcinoma syndrome, jaw cyst-basal cell tumor-skeletal anomaly syndrome, and fifth phacomatosis. OMIM disease identifier reported as #109400; MeSH term in a Gorlin trial record is Basal Cell Nevus Syndrome (D001478).	(kammoun2024theoralfacialmanifestations pages 17-25, murgia2024gorlinsyndromeassociatedbasal pages 1-2, NCT03703310 chunk 3)
Genetics	Rare autosomal dominant tumor-predisposition syndrome caused primarily by loss-of-function PTCH1 variants; SUFU and occasionally PTCH2 are also implicated. About 70–80% of cases have a family history and 20–30% are de novo. PTCH1 variants account for most cases; one review excerpt states PTCH1 variants are responsible for ~90% of cases and another that germline PTCH1 mutation is present in up to 85% of NBCCS patients.	(murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2, onodera2023hedgehogrelatedmutationcauses pages 2-4, kammoun2024theoralfacialmanifestations pages 30-34, wescott2023sustainedsuppressionof pages 2-4)
Core clinical features	Common manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts (OKCs), palmar/plantar pits, falx cerebri calcification, macrocephaly, rib/vertebral anomalies, and craniofacial dysmorphism. Frequency estimates reported in a 2023 review excerpt: BCC prevalence varies by ancestry (15.2% Koreans; 38% African Americans; 80% Caucasians; 76% Australians) with mean onset ~20.3 years; OKC 75% (mean onset 15.5 years); palmar/plantar pits 87%.	(onodera2023hedgehogrelatedmutationcauses pages 2-4, kammoun2024theoralfacialmanifestations pages 17-25, murgia2024gorlinsyndromeassociatedbasal pages 1-2)
Tumor risks	Tumor spectrum includes BCC, medulloblastoma, ovarian fibroma, and cardiac fibroma/fibroelastoma. Medulloblastoma occurs in up to 5% overall in one review excerpt, with much higher risk in SUFU carriers than PTCH1 carriers; the 2024 AACR surveillance paper gives absolute SHH-medulloblastoma risks of about 7–9.2% for SUFU and 0.37–1.1% for PTCH1. Ovarian fibromas occur in 15–25% of patients and are often bilateral (~75% bilateral).	(onodera2023hedgehogrelatedmutationcauses pages 2-4, hansford2024updateoncancer pages 3-4, zhu2023bilateralovarianfibromas pages 1-4, murgia2024gorlinsyndromeassociatedbasal pages 1-2)
Diagnostic criteria	Clinical diagnosis is typically based on major/minor criteria. Major criteria summarized across 2023–2024 sources include: multiple BCCs (>5) or BCC at young age, jaw/odontogenic keratocysts, palmar/plantar pits, lamellar falx calcification, medulloblastoma, and/or an affected first-degree relative. One 2024 study states diagnosis can be made with two major + one minor or one major + three minor criteria; molecular confirmation with heterozygous germline PTCH1 or SUFU pathogenic variants can establish the diagnosis when clinical findings are inconclusive.	(murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2, wescott2023sustainedsuppressionof pages 2-4, kammoun2024theoralfacialmanifestations pages 17-25)
Surveillance	2024 AACR childhood brain tumor predisposition guidance recommends gene-specific surveillance. For SUFU carriers: neurologic exam/head circumference in infancy and diagnosis with checks every 3–4 months until age 5; brain MRI every 3–4 months until age 3, then every 6 months until age 5. For PTCH1 carriers: routine MRI is generally not recommended; surveillance emphasizes clinical neurologic vigilance. Additional screening includes dermatologic exams with sun protection counseling, echocardiogram in infancy for cardiac fibroma, and ovarian ultrasound (PTCH1 once at age 18; SUFU every 3 years in the cited table). PTCH1-focused dental surveillance includes annual orthopantomogram/MRI.	(hansford2024updateoncancer pages 3-4, hansford2024updateoncancer pages 2-3, hansford2024updateoncancer media cb459877, kammoun2024theoralfacialmanifestations pages 30-34)
Treatments	Standard care includes repeated surgery for BCCs/OKCs and multidisciplinary surveillance; for high BCC burden, hedgehog pathway inhibitors (vismodegib, sonidegib) are used. In a 10-patient 2023 Gorlin case series, all patients achieved complete remission, and new BCCs fell from mean 28.3 before treatment to 1.4 during treatment; median time to a new BCC was 47.3 months. A 2024 retrospective Gorlin cohort found sustained HHI treatment suppressed both new and existing BCCs, with sonidegib appearing more effective and better tolerated than vismodegib; schedule adjustment improved tolerability without obvious loss of efficacy.	(wescott2023sustainedsuppressionof pages 1-2, murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 2-4)
Clinical trials	Key Gorlin-specific interventional studies include NCT06050122 (Phase 3, topical patidegib gel 2% vs vehicle; active, not recruiting; primary endpoint: number of new facial BCCs at Month 12), NCT03703310 (Phase 3, patidegib topical gel 2%; completed), NCT02762084 (Phase 2, topical patidegib 2%/4% vs vehicle; completed), NCT01350115 (Phase 2, oral sonidegib/LDE225; completed), and NCT00961896 (Phase 2, topical LDE225; completed).	(NCT06050122 chunk 1, NCT02762084 chunk 1, NCT01350115 chunk 1, NCT00961896 chunk 1)
Epidemiology	Prevalence estimates cluster around 1:57,000, with published ranges of roughly 1:30,827 to 1:164,000; another review gives a broader estimate of 1 in 50,000 to 256,000. Reported sex distribution is similar in males and females, consistent with autosomal dominant inheritance.	(murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2, kammoun2024theoralfacialmanifestations pages 17-25, zhu2023bilateralovarianfibromas pages 1-4)
Treatment safety / real-world implementation	In the multinational NISSO real-world sonidegib safety study (321 laBCC patients; 12.2% with Gorlin syndrome), median exposure was 8.8 months. 88.5% had ≥1 TEAE; common TEAEs were muscle spasms 43.9%, dysgeusia 37.1%, and alopecia 30.2%. TEAEs led to discontinuation in 18.4%, dose reduction in 22.7%, and interruption in 30.5%; serious drug-related TEAEs occurred in 4.1%.	(gutzmer2024interimanalysisof pages 1-2, gutzmer2024interimanalysisof pages 2-4)

Table: This table summarizes high-value knowledge-base facts for Gorlin syndrome, including identifiers, genetics, phenotypes, risks, surveillance, treatments, trials, and epidemiology. It emphasizes quantitative findings and recent evidence useful for structured disease annotation.

1. Disease Information

1.1 Overview (definition; current understanding)

Gorlin syndrome—also called nevoid basal cell carcinoma syndrome (NBCCS)—is a rare autosomal dominant multisystem disorder characterized by developmental anomalies and a strong predisposition to tumors, especially multiple basal cell carcinomas (BCCs) and odontogenic keratocysts (OKCs), with additional risks for medulloblastoma, ovarian fibroma, and cardiac fibroma. (murgia2024gorlinsyndromeassociatedbasal pages 1-2, onodera2023hedgehogrelatedmutationcauses pages 2-4, zhu2023bilateralovarianfibromas pages 1-4)

Recent expert framing (2024): A 2024 retrospective cohort paper defines NBCCS/GS as “a genetic disorder characterized by the development of multiple cutaneous BCCs due to mutations in the hedgehog signaling pathway.” (Cancers, published online 2024-06-07; DOI URL below). (murgia2024gorlinsyndromeassociatedbasal pages 1-2)

1.2 Key identifiers

OMIM (disease): #109400 (explicitly listed). (kammoun2024theoralfacialmanifestations pages 17-25)
MeSH (disease term used in ClinicalTrials.gov): “Basal Cell Nevus Syndrome” D001478 (ClinicalTrials.gov record metadata). (NCT03703310 chunk 3)
Other identifiers (Orphanet, ICD-10/ICD-11, MONDO): Not present in the retrieved evidence snippets; therefore not reported here.

1.3 Synonyms and alternative names

Common synonyms include: - Nevoid basal cell carcinoma syndrome (NBCCS) - Basal cell nevus syndrome (BCNS) - Gorlin–Goltz syndrome - Multiple basal cell carcinoma syndrome - Jaw cyst–basal cell tumor–skeletal anomaly syndrome - Fifth phacomatosis (kammoun2024theoralfacialmanifestations pages 17-25, murgia2024gorlinsyndromeassociatedbasal pages 1-2)

1.4 Source type

Information summarized here is drawn from aggregated disease-level resources (reviews/guidelines) and clinical cohorts/case series (including real-world observational safety data) rather than EHR-derived phenotyping. (hansford2024updateoncancer pages 3-4, gutzmer2024interimanalysisof pages 2-4, wescott2023sustainedsuppressionof pages 1-2)

2. Etiology

2.1 Disease causal factors

Primary cause: germline pathogenic variants in Hedgehog (Hh) pathway negative regulators—most commonly PTCH1, and less commonly SUFU and PTCH2—leading to pathway hyperactivation with developmental anomalies and tumor predisposition. (onodera2023hedgehogrelatedmutationcauses pages 2-4, murgia2024gorlinsyndromeassociatedbasal pages 1-2)

Inheritance: autosomal dominant; a large fraction arises de novo (20–30% in multiple reports). (murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2)

2.2 Risk factors

Genetic risk factors

PTCH1 loss-of-function is the dominant genetic driver in most cases (one 2024 cohort states PTCH1 LoF as primary cause; a 2023 review describes PTCH1 as the most common causal gene and notes PTCH2/SUFU involvement). (murgia2024gorlinsyndromeassociatedbasal pages 1-2, onodera2023hedgehogrelatedmutationcauses pages 2-4)
Gene-specific medulloblastoma risk differs strongly: SUFU carriers have substantially higher absolute SHH-medulloblastoma risks than PTCH1 carriers (see §9 and §11 for surveillance implications). (hansford2024updateoncancer pages 3-4)

Environmental/medical exposure risk factors

Ionizing radiation should be avoided when feasible due to tumor induction concerns in NBCCS; this is emphasized in pediatric surveillance guidance (sun protection counseling and avoidance of ionizing radiation are explicitly noted). (hansford2024updateoncancer pages 2-3)

2.3 Protective factors / gene–environment interactions

No explicit protective genetic variants or quantified gene–environment interaction models were found in the retrieved evidence set. Risk mitigation is primarily via exposure avoidance (radiation, UV) and surveillance. (hansford2024updateoncancer pages 2-3)

3. Phenotypes (clinical features)

3.1 High-frequency phenotypes and reported frequencies

A 2023 review focusing on Hedgehog-related skeletal/tumor disorders provides quantitative phenotype frequencies for Gorlin syndrome: - Palmar/plantar pits: ~87% (onodera2023hedgehogrelatedmutationcauses pages 2-4) - Odontogenic keratocysts (OKC): ~75%, mean onset ~15.5 years (onodera2023hedgehogrelatedmutationcauses pages 2-4) - Basal cell carcinoma (BCC): frequency varies by ancestry (reported values: 15.2% Koreans; 38% African Americans; 80% Caucasians; 76% Australians) with mean onset ~20.3 years (onodera2023hedgehogrelatedmutationcauses pages 2-4) - Medulloblastoma: “up to 5% in the first 2 years of life” in the cited review summary (onodera2023hedgehogrelatedmutationcauses pages 2-4)

Other commonly described manifestations across 2023–2024 clinical series/reviews include macrocephaly, craniofacial dysmorphism, rib/vertebral anomalies, falx cerebri calcification, and multiple BCCs (often dozens to hundreds over a lifetime). (wescott2023sustainedsuppressionof pages 1-2, kammoun2024theoralfacialmanifestations pages 17-25, murgia2024gorlinsyndromeassociatedbasal pages 1-2)

3.2 Example phenotype-to-HPO suggestions (non-exhaustive)

The retrieved texts did not include formal HPO mappings; below are suggested HPO-aligned phenotype labels for knowledge-base normalization (term IDs should be resolved against the HPO release used in your KB pipeline): - Multiple basal cell carcinomas → Basal cell carcinoma - Odontogenic keratocysts → Odontogenic keratocyst - Palmar/plantar pits → Palmar pits, Plantar pits - Macrocephaly → Macrocephaly - Falx cerebri calcification → Intracranial calcification / Falx cerebri calcification - Rib anomalies (e.g., bifid ribs) → Bifid rib / Rib anomaly - Medulloblastoma (SHH-activated) → Medulloblastoma - Ovarian fibroma → Ovarian fibroma - Cardiac fibroma → Cardiac fibroma

3.3 Quality of life impact

High BCC burden can lead to repeated procedures and disfigurement; a 2024 cohort describes that patients “may need dozens or even hundreds of surgical procedures in their lifetime,” which can be severely scarring/disfiguring, motivating systemic pathway-targeted therapies. (murgia2024gorlinsyndromeassociatedbasal pages 1-2)

4. Genetic / Molecular Information

4.1 Causal genes

PTCH1 (primary; tumor suppressor; Hh receptor) (onodera2023hedgehogrelatedmutationcauses pages 2-4, murgia2024gorlinsyndromeassociatedbasal pages 1-2)
SUFU (negative regulator of GLI; high SHH-medulloblastoma risk subgroup) (hansford2024updateoncancer pages 3-4)
PTCH2 (less common; occasionally implicated) (onodera2023hedgehogrelatedmutationcauses pages 2-4, wescott2023sustainedsuppressionof pages 2-4)

4.2 Pathogenic variant types and functional consequences

Mechanistic class: typically loss-of-function of pathway repressors → constitutive pathway signaling. In PTCH1-associated disease, PTCH1 normally represses SMO; loss leads to downstream GLI activation. (onodera2023hedgehogrelatedmutationcauses pages 2-4)

Hard-to-detect variant class (2024 development): Mochizuki et al. describe a germline mobile-element insertion in PTCH1 (Alu insertion) that standard panel and genome sequencing did not initially detect, requiring manual review and RNA-seq confirmation: - Variant: PTCH1 c.361_362insAlu (molecular confirmation via clinical RNA sequencing) (mochizuki2024germlineptch1c.361362insalu pages 1-2, mochizuki2024germlineptch1c.361362insalu pages 3-4) - Clinical implication: supports integrating RNA-seq with DNA testing for cryptic splicing/insertion events when phenotype is strong. (mochizuki2024germlineptch1c.361362insalu pages 2-3)

Direct abstract quote (diagnostic genomics; 2024): “Clinical RNA sequencing further demonstrated an Alu insertion at this region (PTCH1: c.361_362insAlu), providing molecular confirmation of Gorlin syndrome.” (Mochizuki et al., Am J Med Genet A, Jun 2024; https://doi.org/10.1002/ajmg.a.63788). (mochizuki2024germlineptch1c.361362insalu pages 1-2)

4.3 Modifier genes / epigenetics / chromosomal abnormalities

The retrieved evidence mentions SUFU/PTCH2 as contributors/modifiers of expressivity but does not provide specific validated modifier loci, epigenetic signatures, or recurrent chromosomal abnormalities. (murgia2024gorlinsyndromeassociatedbasal pages 1-2)

5. Environmental Information

5.1 Environmental/lifestyle factors

The retrieved 2024 pediatric surveillance guideline emphasizes sun protection counseling and avoidance of ionizing radiation due to tumor risks in NBCCS. (hansford2024updateoncancer pages 2-3)

No additional quantified toxin/occupational exposure associations were present in the retrieved evidence set.

6. Mechanism / Pathophysiology

6.1 Core pathway: Hedgehog signaling dysregulation

A 2023 mechanistic review describes Gorlin syndrome as involving mutations in negative regulators (PTCH1/PTCH2/SUFU) of the Hedgehog pathway. PTCH1 encodes a multipass transmembrane receptor for SHH/IHH/DHH ligands and represses SMO; PTCH1 loss leads to constitutive SMO activation and aberrant activation of GLI transcription factors, driving developmental anomalies and tumorigenesis. (onodera2023hedgehogrelatedmutationcauses pages 2-4)

6.2 Causal chain (gene → pathway → cell behavior → phenotype)

Upstream trigger: germline loss-of-function variant in PTCH1 (or SUFU/PTCH2) (onodera2023hedgehogrelatedmutationcauses pages 2-4, murgia2024gorlinsyndromeassociatedbasal pages 1-2)
Pathway effect: disinhibition of SMO → GLI activation (onodera2023hedgehogrelatedmutationcauses pages 2-4)
Cellular processes: dysregulated proliferation/differentiation in skin adnexal/epithelial lineages and craniofacial/bone development programs (inferred from pathway’s role in development and tumorigenesis as described) (onodera2023hedgehogrelatedmutationcauses pages 2-4)
Clinical manifestations: multiple BCCs, odontogenic cysts, skeletal anomalies, and early childhood SHH-medulloblastoma in high-risk genotypes (onodera2023hedgehogrelatedmutationcauses pages 2-4, hansford2024updateoncancer pages 3-4)

6.3 Suggested GO / CL annotations (for KB normalization)

The retrieved sources do not provide explicit GO/CL terms; plausible normalizations consistent with described biology include: - GO biological process (suggestions): Hedgehog signaling pathway; regulation of cell proliferation; embryonic skeletal system development; epithelial cell proliferation. - CL cell types (suggestions): basal keratinocyte; hair follicle epithelial cell; odontogenic epithelial cell; cerebellar granule neuron precursor (relevant to SHH-medulloblastoma).

7. Anatomical Structures Affected

7.1 Organ/tissue systems (high-confidence from retrieved evidence)

Skin: multiple basal cell carcinomas (onodera2023hedgehogrelatedmutationcauses pages 2-4, wescott2023sustainedsuppressionof pages 1-2)
Jaw/maxillofacial tissues: odontogenic keratocysts (onodera2023hedgehogrelatedmutationcauses pages 2-4, kammoun2024theoralfacialmanifestations pages 17-25)
Central nervous system: SHH-medulloblastoma risk (especially SUFU) (hansford2024updateoncancer pages 3-4)
Ovary: ovarian fibromas (often bilateral) (zhu2023bilateralovarianfibromas pages 1-4)
Heart: cardiac fibroma (screened in infancy per guideline) (hansford2024updateoncancer pages 2-3)

7.2 Suggested UBERON mappings (labels)

Skin; jaw; cerebellum/brain; ovary; heart.

8. Temporal Development (natural history)

8.1 Onset patterns

OKCs: mean onset ~15.5 years (childhood/adolescence). (onodera2023hedgehogrelatedmutationcauses pages 2-4)
BCCs: mean onset ~20.3 years with strong ancestry-dependent penetrance estimates in the cited review. (onodera2023hedgehogrelatedmutationcauses pages 2-4)
Medulloblastoma: concentrated in infancy/early childhood; surveillance recommendations focus on the first 5 years (SUFU subgroup). (hansford2024updateoncancer pages 3-4, hansford2024updateoncancer pages 2-3)

8.2 Progression/course

The disease course is lifelong with repeated tumor occurrence (particularly BCCs), often requiring repeated local treatments or systemic pathway inhibition when burden is high. (wescott2023sustainedsuppressionof pages 1-2, murgia2024gorlinsyndromeassociatedbasal pages 1-2)

9. Inheritance and Population

9.1 Inheritance

Autosomal dominant. (kammoun2024theoralfacialmanifestations pages 30-34, murgia2024gorlinsyndromeassociatedbasal pages 1-2)

9.2 De novo rate

Across 2023–2024 sources, ~20–30% of cases are attributed to de novo pathogenic variation, with ~70–80% having family history. (murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2)

9.3 Epidemiology (prevalence)

Prevalence estimates in the retrieved sources cluster around: - ~1:57,000 with a reported range 1:30,827–1:164,000 (northwest England estimate cited in 2024 cohort and 2023 case series). (murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2) - A broader estimate of 1 in 50,000 to 256,000 is also reported in a 2024 review excerpt. (kammoun2024theoralfacialmanifestations pages 17-25)

9.4 Sex ratio

Similar rates in males and females are expected/observed given autosomal dominant inheritance (explicitly stated in a 2023 case-series excerpt). (wescott2023sustainedsuppressionof pages 1-2)

10. Diagnostics

10.1 Clinical diagnostic criteria (major/minor)

Across 2023–2024 sources, diagnosis is described as based on combinations of major/minor criteria.

Major criteria (commonly listed): - Multiple BCCs or early-onset BCC burden (e.g., >5 or BCC at young age) - Jaw odontogenic keratocysts - Palmar/plantar pits - Lamellar calcification of the falx cerebri - Medulloblastoma - First-degree relative with NBCCS (murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2)

Rule-based diagnosis (example reported in 2024 cohort): “two major + one minor, or one major + three minor criteria.” (murgia2024gorlinsyndromeassociatedbasal pages 1-2)

10.2 Molecular diagnosis and genetic testing strategy

Key concept: Molecular confirmation with heterozygous germline PTCH1 or SUFU pathogenic variants can establish diagnosis when clinical features are incomplete. (wescott2023sustainedsuppressionof pages 2-4)

2024 development (DNA+RNA sequencing): Mochizuki et al. show that standard clinical DNA approaches (panel/GS) may miss mobile-element insertions; paired tumor/normal exome plus RNA-seq can provide confirmation (PTCH1 c.361_362insAlu). (mochizuki2024germlineptch1c.361362insalu pages 1-2, mochizuki2024germlineptch1c.361362insalu pages 3-4)

10.3 Imaging and other testing

Dental imaging (orthopantomogram) is explicitly included in surveillance/diagnostic workflows for PTCH1 carriers; MRI can substitute in some guidance. (hansford2024updateoncancer pages 2-3, hansford2024updateoncancer media cb459877)
Brain MRI for medulloblastoma surveillance is recommended in SUFU carriers in early childhood (see §11). (hansford2024updateoncancer pages 2-3)

10.4 Differential diagnosis

No explicit differential diagnosis list was present in the retrieved evidence snippets.

11. Outcome / Prognosis

11.1 Tumor risks and prognostic stratification (gene-specific)

A key 2024 guideline update provides absolute SHH-medulloblastoma risks: - SUFU: ~7%–9.2% - PTCH1: ~0.37%–1.1% (hansford2024updateoncancer pages 3-4)

This genotype risk stratification drives surveillance intensity (SUFU vs PTCH1; see below). (hansford2024updateoncancer pages 3-4, hansford2024updateoncancer pages 2-3)

11.2 Morbidity and burden

The principal morbidity in many patients stems from repeated BCC occurrence and associated procedural burden/disfigurement, motivating systemic therapies when local therapy becomes impractical. (murgia2024gorlinsyndromeassociatedbasal pages 1-2, wescott2023sustainedsuppressionof pages 1-2)

12. Treatment

12.1 Local/surgical management (current practice)

Patients frequently undergo repeated excisions or other local therapies for BCCs and management of OKCs; the 2024 cohort emphasizes high lifetime procedural burden (“dozens or even hundreds of surgical procedures”). (murgia2024gorlinsyndromeassociatedbasal pages 1-2)

12.2 Targeted pharmacotherapy: Hedgehog pathway inhibitors (HHIs)

Agents: vismodegib and sonidegib (SMO inhibitors) are used to suppress BCC development in high-burden NBCCS patients. (wescott2023sustainedsuppressionof pages 1-2, murgia2024gorlinsyndromeassociatedbasal pages 1-2)

Effectiveness in Gorlin syndrome cohorts (2023–2024): - In a 10-patient case series (published 2023-10; Current Oncology; https://doi.org/10.3390/curroncol30100661), “All patients achieved a complete remission,” and mean new tumors decreased from 28.3 before treatment to 1.4 during treatment (p=0.0048); median time to a new BCC was 47.3 months. (wescott2023sustainedsuppressionof pages 1-2) - In a 16-patient retrospective series (published 2024-06-07; Cancers; https://doi.org/10.3390/cancers16122166), sustained HHI therapy suppressed both new and existing BCCs, and sonidegib was reported as having superior efficacy and safety vs vismodegib, with schedule adjustments improving tolerability. (murgia2024gorlinsyndromeassociatedbasal pages 1-2)

Adverse effects (class effects): muscle cramps/spasms, taste changes (dysgeusia), alopecia, fatigue/asthenia are commonly noted. (wescott2023sustainedsuppressionof pages 1-2, wescott2023sustainedsuppressionof pages 2-4)

12.3 Real-world implementation and safety (2024 post-authorization data)

The NISSO non-interventional post-authorization sonidegib study (published 2024-11; BMC Cancer; https://doi.org/10.1186/s12885-024-13101-z) enrolled 321 laBCC patients (median age 77), including 12.2% (n=39) with Gorlin syndrome. (gutzmer2024interimanalysisof pages 2-4)

Key safety statistics: - ≥1 TEAE: 88.5% - Most common TEAEs: muscle spasms 43.9%, dysgeusia 37.1%, alopecia 30.2% - TEAE-related: discontinuation 18.4%, dose reduction 22.7%, interruption 30.5% - Serious drug-related TEAEs: 4.1% (gutzmer2024interimanalysisof pages 2-4)

12.4 MAXO suggestions (treatment actions)

Suggested MAXO-normalizations (labels) consistent with described management: - Hedgehog pathway inhibitor therapy - Dermatologic surveillance - Surgical excision of basal cell carcinoma - Dental/maxillofacial surgery for odontogenic keratocysts - Genetic counseling

13. Prevention

13.1 Primary/secondary prevention

Guideline-level prevention focuses on: - Sun protection counseling - Avoidance of ionizing radiation when feasible - Surveillance to detect medulloblastoma and other tumors early (gene-specific) (hansford2024updateoncancer pages 2-3)

13.2 Surveillance (gene-specific; 2024 AACR guidance)

The 2024 AACR working group recommends gene-tailored surveillance, particularly for early childhood SHH-medulloblastoma. (hansford2024updateoncancer pages 3-4)

Key surveillance elements for Gorlin syndrome (from Table 1): - SUFU carriers: brain MRI q3–4 months until age 3, then q6 months until age 5; neurologic exam/head circumference checks q3–4 months until age 5. (hansford2024updateoncancer pages 2-3, hansford2024updateoncancer media cb459877) - PTCH1 carriers: routine neuroimaging generally not recommended; emphasize clinical vigilance; dental and jaw surveillance using orthopantomogram or MRI. (hansford2024updateoncancer pages 3-4, hansford2024updateoncancer media cb459877) - Echocardiogram: baseline in infancy (<6 months) to evaluate cardiac fibroma. (hansford2024updateoncancer pages 2-3, hansford2024updateoncancer media cb459877) - Ovarian ultrasound: per Table 1, PTCH1 “once at 18 years,” SUFU “every 3 years starting at 5 years” (and MRI substitution if ultrasound not feasible). (hansford2024updateoncancer pages 2-3, hansford2024updateoncancer media cb459877)

Visual evidence: the extracted Table 1 image segment containing these intervals is provided in the cited figure. (hansford2024updateoncancer media cb459877)

14. Other Species / Natural Disease

No evidence for naturally occurring Gorlin syndrome analogs in non-human species was found in the retrieved sources.

15. Model Organisms

The retrieved 2023–2024 evidence set did not include explicit descriptions of specific named engineered animal models (e.g., Ptch1+/− mice) or in vitro models, beyond general statements that Hedgehog signaling is essential in development and tumorigenesis. This is an evidence gap in the current retrieval and should be filled by targeted searches of model organism databases (MGI/IMPC) if required for your KB. (onodera2023hedgehogrelatedmutationcauses pages 2-4)

Recent developments (2023–2024 highlights)

Gene-specific surveillance refined for childhood SHH-medulloblastoma risk: SUFU carriers receive routine MRI surveillance in early childhood, while PTCH1 carriers generally do not, reflecting the large absolute risk differential. (Clin Cancer Res, 2024-04; https://doi.org/10.1158/1078-0432.ccr-23-4033). (hansford2024updateoncancer pages 3-4, hansford2024updateoncancer pages 2-3)
Diagnostics advancing beyond standard DNA panels: 2024 evidence shows RNA sequencing can confirm cryptic mobile-element insertions in PTCH1 missed by routine testing, supporting DNA+RNA workflows in strong clinical suspicion cases. (Am J Med Genet A, 2024-06; https://doi.org/10.1002/ajmg.a.63788). (mochizuki2024germlineptch1c.361362insalu pages 1-2, mochizuki2024germlineptch1c.361362insalu pages 3-4)
Real-world HHI tolerability quantified in routine practice (including Gorlin subgroup): NISSO provides contemporary AE/discontinuation rates for sonidegib, with 12.2% Gorlin patients. (BMC Cancer, 2024-11; https://doi.org/10.1186/s12885-024-13101-z). (gutzmer2024interimanalysisof pages 2-4)
New prevention-focused topical Hh inhibitor trials ongoing: Phase 3 topical patidegib (2%) prevention trial active (not recruiting) targeting reduction of new facial BCCs in PTCH1-confirmed Gorlin syndrome. (ClinicalTrials.gov NCT06050122; start 2024-03-17). (NCT06050122 chunk 1)

Key URLs and publication dates (selected)

Hansford et al. Clinical Cancer Research (2024-04): https://doi.org/10.1158/1078-0432.ccr-23-4033 (hansford2024updateoncancer pages 3-4)
Gutzmer et al. BMC Cancer (2024-11): https://doi.org/10.1186/s12885-024-13101-z (gutzmer2024interimanalysisof pages 1-2)
Murgia et al. Cancers (2024-06-07): https://doi.org/10.3390/cancers16122166 (murgia2024gorlinsyndromeassociatedbasal pages 1-2)
Mochizuki et al. Am J Med Genet A (2024-06): https://doi.org/10.1002/ajmg.a.63788 (mochizuki2024germlineptch1c.361362insalu pages 1-2)
Wescott & Samlowski Current Oncology (2023-10-16): https://doi.org/10.3390/curroncol30100661 (wescott2023sustainedsuppressionof pages 1-2)
Zhu et al. Diagnostic Pathology (2023-10): https://doi.org/10.1186/s13000-023-01406-9 (zhu2023bilateralovarianfibromas pages 1-4)
ClinicalTrials.gov NCT06050122 (patidegib gel 2% Phase 3; started 2024-03-17): evidence extracted from trial record (NCT06050122 chunk 1)

Limitations of this report (due to retrieved evidence)

PMIDs were not present in the retrieved tool excerpts; DOIs and ClinicalTrials.gov identifiers are provided instead.
ICD-10/ICD-11, Orphanet, and MONDO identifiers were not found in the retrieved texts.
Model organism evidence was not directly retrieved; additional targeted searches are required for that section.

References

(kammoun2024theoralfacialmanifestations pages 17-25): K Kammoun. The oral-facial manifestations of gorlin syndrome. Unknown journal, 2024.
(murgia2024gorlinsyndromeassociatedbasal pages 1-2): Giulia Murgia, Luca Valtellini, Nerina Denaro, Gianluca Nazzaro, Paolo Bortoluzzi, Valentina Benzecry, Emanuela Passoni, and Angelo Valerio Marzano. Gorlin syndrome-associated basal cell carcinomas treated with vismodegib or sonidegib: a retrospective study. Cancers, 16:2166, Jun 2024. URL: https://doi.org/10.3390/cancers16122166, doi:10.3390/cancers16122166. This article has 15 citations.
(NCT03703310 chunk 3): Study of Patidegib Topical Gel, 2%, for the Reduction of Disease Burden of Persistently Developing Basal Cell Carcinomas (BCCs) in Subjects With Basal Cell Nevus Syndrome (Gorlin Syndrome). Sol-Gel Technologies, Ltd.. 2019. ClinicalTrials.gov Identifier: NCT03703310
(wescott2023sustainedsuppressionof pages 1-2): Raquel Wescott and Wolfram Samlowski. Sustained suppression of gorlin syndrome-associated basal cell carcinomas with vismodegib or sonidegib: a case series. Current Oncology, 30:9156-9167, Oct 2023. URL: https://doi.org/10.3390/curroncol30100661, doi:10.3390/curroncol30100661. This article has 7 citations.
(onodera2023hedgehogrelatedmutationcauses pages 2-4): Shoko Onodera and Toshifumi Azuma. Hedgehog-related mutation causes bone malformations with or without hereditary gene mutations. International Journal of Molecular Sciences, 24:12903, Aug 2023. URL: https://doi.org/10.3390/ijms241612903, doi:10.3390/ijms241612903. This article has 10 citations.
(kammoun2024theoralfacialmanifestations pages 30-34): K Kammoun. The oral-facial manifestations of gorlin syndrome. Unknown journal, 2024.
(wescott2023sustainedsuppressionof pages 2-4): Raquel Wescott and Wolfram Samlowski. Sustained suppression of gorlin syndrome-associated basal cell carcinomas with vismodegib or sonidegib: a case series. Current Oncology, 30:9156-9167, Oct 2023. URL: https://doi.org/10.3390/curroncol30100661, doi:10.3390/curroncol30100661. This article has 7 citations.
(hansford2024updateoncancer pages 3-4): Jordan R. Hansford, Anirban Das, Rose B. McGee, Yoshiko Nakano, Jack Brzezinski, Sarah R. Scollon, Surya P. Rednam, Jaclyn Schienda, Orli Michaeli, Sun Young Kim, Mary-Louise C. Greer, Rosanna Weksberg, Douglas R. Stewart, William D. Foulkes, Uri Tabori, Kristian W. Pajtler, Stefan M. Pfister, Garrett M. Brodeur, and Junne Kamihara. Update on cancer predisposition syndromes and surveillance guidelines for childhood brain tumors. Clinical cancer research : an official journal of the American Association for Cancer Research, 30:2342-2350, Apr 2024. URL: https://doi.org/10.1158/1078-0432.ccr-23-4033, doi:10.1158/1078-0432.ccr-23-4033. This article has 51 citations.
(zhu2023bilateralovarianfibromas pages 1-4): Menghan Zhu, Jun Li, Jie Duan, Jing Yang, Weiyong Gu, and Wei Jiang. Bilateral ovarian fibromas as the sole manifestation of gorlin syndrome in a 22-year-old woman: a case report and literature review. Diagnostic Pathology, Oct 2023. URL: https://doi.org/10.1186/s13000-023-01406-9, doi:10.1186/s13000-023-01406-9. This article has 3 citations and is from a peer-reviewed journal.
(hansford2024updateoncancer pages 2-3): Jordan R. Hansford, Anirban Das, Rose B. McGee, Yoshiko Nakano, Jack Brzezinski, Sarah R. Scollon, Surya P. Rednam, Jaclyn Schienda, Orli Michaeli, Sun Young Kim, Mary-Louise C. Greer, Rosanna Weksberg, Douglas R. Stewart, William D. Foulkes, Uri Tabori, Kristian W. Pajtler, Stefan M. Pfister, Garrett M. Brodeur, and Junne Kamihara. Update on cancer predisposition syndromes and surveillance guidelines for childhood brain tumors. Clinical cancer research : an official journal of the American Association for Cancer Research, 30:2342-2350, Apr 2024. URL: https://doi.org/10.1158/1078-0432.ccr-23-4033, doi:10.1158/1078-0432.ccr-23-4033. This article has 51 citations.
(hansford2024updateoncancer media cb459877): Jordan R. Hansford, Anirban Das, Rose B. McGee, Yoshiko Nakano, Jack Brzezinski, Sarah R. Scollon, Surya P. Rednam, Jaclyn Schienda, Orli Michaeli, Sun Young Kim, Mary-Louise C. Greer, Rosanna Weksberg, Douglas R. Stewart, William D. Foulkes, Uri Tabori, Kristian W. Pajtler, Stefan M. Pfister, Garrett M. Brodeur, and Junne Kamihara. Update on cancer predisposition syndromes and surveillance guidelines for childhood brain tumors. Clinical cancer research : an official journal of the American Association for Cancer Research, 30:2342-2350, Apr 2024. URL: https://doi.org/10.1158/1078-0432.ccr-23-4033, doi:10.1158/1078-0432.ccr-23-4033. This article has 51 citations.
(NCT06050122 chunk 1): Efficacy and Safety of Patidegib Gel 2% for Preventing Basal Cell Carcinomas on the Face of Adults With Gorlin Syndrome. Sol-Gel Technologies, Ltd.. 2024. ClinicalTrials.gov Identifier: NCT06050122
(NCT02762084 chunk 1): Trial of Patidegib Gel 2%, 4%, and Vehicle to Decrease the Number of Surgically Eligible Basal Cell Carcinomas in Gorlin Syndrome Patients. PellePharm, Inc.. 2016. ClinicalTrials.gov Identifier: NCT02762084
(NCT01350115 chunk 1): Efficacy, Safety and Pharmacokinetics of Oral LDE225 in Treatment of Patients With Nevoid Basal Cell Carcinoma Syndrome (NBCCS). Novartis Pharmaceuticals. 2011. ClinicalTrials.gov Identifier: NCT01350115
(NCT00961896 chunk 1): A Trial to Evaluate the Safety, Local Tolerability, Pharmacokinetics and Pharmacodynamics of LDE225 on Skin Basal Cell Carcinomas in Gorlin Syndrome Patients. Novartis Pharmaceuticals. 2009. ClinicalTrials.gov Identifier: NCT00961896
(gutzmer2024interimanalysisof pages 1-2): Ralf Gutzmer, Ulrike Leiter, Peter Mohr, Katharina C. Kähler, Paolo Antonio Ascierto, Massimiliano Scalvenzi, Ketty Peris, Gemma María Pérez-Pastor, Ricardo Fernández-de-Misa, Rafael Botella-Estrada, Robert E. Hunger, Serena Martelli, Nur Güneli, Ramon Arntz, and Axel Hauschild. Interim analysis of the multinational, post-authorization safety study (nisso) to assess the long-term safety of sonidegib in patients with locally advanced basal cell carcinoma. BMC Cancer, Nov 2024. URL: https://doi.org/10.1186/s12885-024-13101-z, doi:10.1186/s12885-024-13101-z. This article has 11 citations and is from a peer-reviewed journal.
(gutzmer2024interimanalysisof pages 2-4): Ralf Gutzmer, Ulrike Leiter, Peter Mohr, Katharina C. Kähler, Paolo Antonio Ascierto, Massimiliano Scalvenzi, Ketty Peris, Gemma María Pérez-Pastor, Ricardo Fernández-de-Misa, Rafael Botella-Estrada, Robert E. Hunger, Serena Martelli, Nur Güneli, Ramon Arntz, and Axel Hauschild. Interim analysis of the multinational, post-authorization safety study (nisso) to assess the long-term safety of sonidegib in patients with locally advanced basal cell carcinoma. BMC Cancer, Nov 2024. URL: https://doi.org/10.1186/s12885-024-13101-z, doi:10.1186/s12885-024-13101-z. This article has 11 citations and is from a peer-reviewed journal.
(mochizuki2024germlineptch1c.361362insalu pages 1-2): Aaron Y. Mochizuki, Chinmayee B. Nagaraj, Douglas Depoorter, Kathleen M. Schieffer, and Sun Young Kim. Germline ptch1: c.361_362insalu alteration identified by comprehensive exome and rna sequencing in a patient with gorlin syndrome. American Journal of Medical Genetics Part A, Jun 2024. URL: https://doi.org/10.1002/ajmg.a.63788, doi:10.1002/ajmg.a.63788. This article has 1 citations.
(mochizuki2024germlineptch1c.361362insalu pages 3-4): Aaron Y. Mochizuki, Chinmayee B. Nagaraj, Douglas Depoorter, Kathleen M. Schieffer, and Sun Young Kim. Germline ptch1: c.361_362insalu alteration identified by comprehensive exome and rna sequencing in a patient with gorlin syndrome. American Journal of Medical Genetics Part A, Jun 2024. URL: https://doi.org/10.1002/ajmg.a.63788, doi:10.1002/ajmg.a.63788. This article has 1 citations.
(mochizuki2024germlineptch1c.361362insalu pages 2-3): Aaron Y. Mochizuki, Chinmayee B. Nagaraj, Douglas Depoorter, Kathleen M. Schieffer, and Sun Young Kim. Germline ptch1: c.361_362insalu alteration identified by comprehensive exome and rna sequencing in a patient with gorlin syndrome. American Journal of Medical Genetics Part A, Jun 2024. URL: https://doi.org/10.1002/ajmg.a.63788, doi:10.1002/ajmg.a.63788. This article has 1 citations.

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Mappings

Definitions

Inheritance

Subtypes

Mechanistic Hypotheses

Discussions and Knowledge Gaps

Pathophysiology

Pathograph

Phenotypes

Genetic Associations

External Assertions

Medical Actions

Environmental Factors

Diagnosis

Progression

Prevalence

Source YAML

References & Deep Research

References

Deep Research

Gorlin Syndrome (Nevoid Basal Cell Carcinoma Syndrome; NBCCS) — Disease Characteristics Research Report

Target Disease

Evidence base and scope

Structured summary table

1. Disease Information

1.1 Overview (definition; current understanding)

1.2 Key identifiers

1.3 Synonyms and alternative names

1.4 Source type

2. Etiology

2.1 Disease causal factors

2.2 Risk factors

Genetic risk factors

Environmental/medical exposure risk factors

2.3 Protective factors / gene–environment interactions

3. Phenotypes (clinical features)

3.1 High-frequency phenotypes and reported frequencies

3.2 Example phenotype-to-HPO suggestions (non-exhaustive)

3.3 Quality of life impact

4. Genetic / Molecular Information

4.1 Causal genes

4.2 Pathogenic variant types and functional consequences

4.3 Modifier genes / epigenetics / chromosomal abnormalities

5. Environmental Information

5.1 Environmental/lifestyle factors

6. Mechanism / Pathophysiology

6.1 Core pathway: Hedgehog signaling dysregulation

6.2 Causal chain (gene → pathway → cell behavior → phenotype)

6.3 Suggested GO / CL annotations (for KB normalization)

7. Anatomical Structures Affected

7.1 Organ/tissue systems (high-confidence from retrieved evidence)

7.2 Suggested UBERON mappings (labels)

8. Temporal Development (natural history)

8.1 Onset patterns

8.2 Progression/course

9. Inheritance and Population

9.1 Inheritance

9.2 De novo rate

9.3 Epidemiology (prevalence)

9.4 Sex ratio

10. Diagnostics

10.1 Clinical diagnostic criteria (major/minor)

10.2 Molecular diagnosis and genetic testing strategy

10.3 Imaging and other testing

10.4 Differential diagnosis

11. Outcome / Prognosis

11.1 Tumor risks and prognostic stratification (gene-specific)

11.2 Morbidity and burden

12. Treatment

12.1 Local/surgical management (current practice)

12.2 Targeted pharmacotherapy: Hedgehog pathway inhibitors (HHIs)

12.3 Real-world implementation and safety (2024 post-authorization data)

12.4 MAXO suggestions (treatment actions)

13. Prevention

13.1 Primary/secondary prevention

13.2 Surveillance (gene-specific; 2024 AACR guidance)

14. Other Species / Natural Disease

15. Model Organisms