X-linked Hypohidrotic Ectodermal Dysplasia

Genetic MONDO:0010585 Pathograph 27 Show in embeddings browser Ectodermal Dysplasia

X-linked hypohidrotic ectodermal dysplasia (XLHED, Christ-Siemens-Touraine syndrome) is an X-linked disorder caused by pathogenic variants in EDA, which encodes the TNF-superfamily ligand ectodysplasin A. Deficient EDA-EDAR-EDARADD signaling reduces canonical NF-kappaB activation, disrupting ectodermal placode formation and the morphogenesis of hair follicles, teeth, eccrine sweat glands, and other secretory glands. Affected males typically have the classic triad of hypohidrosis, sparse hair, and hypodontia, often with conical teeth. Heterozygous females may show variable, usually milder manifestations. Markedly deficient sweating creates a risk of life-threatening hyperthermia, particularly in infancy and early childhood. In a Danish population study, molecularly confirmed XLHED had a point prevalence of 1.6 per 100,000.

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1
Inheritance
9
Pathophys.
12
Phenotypes
27
Pathograph
1
Genes
1
Variants
5
Medical Actions
2
Differentials
1
Trials
1
Models
6
References
1
Deep Research
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Inheritance

1
X-linked HP:0001417
EDA-related HED is inherited in an X-linked manner. Hemizygous males who inherit the familial pathogenic variant are affected; heterozygous females may manifest ectodermal-dysplasia features.
X-linked inheritance
Show evidence (3 references)
PMID:20301291 SUPPORT Human Clinical
"EDA-related HED is inherited in an X-linked manner."
GeneReviews directly establishes the inheritance mode of EDA-related HED.
PMID:20301291 SUPPORT Human Clinical
"If the mother of a proband is heterozygous for an EDA pathogenic variant, the chance of the mother transmitting it in each pregnancy is 50%. If the father of the proband has an EDA pathogenic variant, he will transmit it to all his daughters and none of his sons. Males who inherit the pathogenic..."
Defines transmission risks and sex-dependent manifestations for X-linked HED.
PMID:21357618 SUPPORT Human Clinical
"In all 5 heterozygous females, some sweat was detected, but generally less than in female controls."
Objective sweat testing documents manifestations in heterozygous females, supporting the broader X-linked term rather than an assertion that female heterozygotes are uniformly unaffected.

Pathophysiology

9
EDA Ligand Deficiency
Pathogenic EDA variants cause complete or partial deficiency of ectodysplasin A1, removing the extracellular ligand that normally activates EDAR during ectodermal-appendage development.
EDA hgnc:3157 HUGO Gene Nomenclature Committee (hgnc) Relation: this pathophysiological event involves this gene This pathophysiological event involves EDA (hgnc:3157). hgnc:3157 is a gene from the HUGO Gene Nomenclature Committee.
Show evidence (1 reference)
PMID:37108325 SUPPORT Human Clinical
"X-linked hypohidrotic ectodermal dysplasia (XLHED), caused by a genetic deficiency of ectodysplasin A1 (EDA1), is a rare developmental disorder of ectodermal derivatives such as hair, sweat glands, and teeth."
Directly identifies EDA1 deficiency as the initiating molecular lesion in XLHED.
EDA-EDAR-EDARADD Canonical NF-kappaB Signaling Failure
EDA ligand deficiency prevents effective EDAR activation and EDARADD-dependent signaling, reducing canonical NF-kappaB transcriptional activity in developing surface ectoderm. This also disrupts downstream Wnt, SHH, FGF, and TGF-beta pathway effectors involved in epithelial-mesenchymal interactions.
surface ectodermal cell CL:0000114 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves surface ectodermal cell (CL:0000114). CL:0000114 is a cell type from the Cell Ontology. keratinocyte CL:0000312 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves keratinocyte (CL:0000312). CL:0000312 is a cell type from the Cell Ontology.
canonical NF-kappaB signal transduction GO:0007249 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased canonical NF-kappaB signal transduction (GO:0007249). GO:0007249 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (2 references)
PMID:24070496 SUPPORT Other
"It comprises three main gene products: EDA, a ligand that belongs to the tumor necrosis factor (TNF)-α family, EDAR, a receptor related to the TNFα receptors, and EDARADD, a specific adaptor. This core pathway relies on downstream NF-κB pathway activation to regulate target genes."
Defines the EDA-EDAR-EDARADD cascade and its dependence on NF-kappaB activation.
PMID:24508088 SUPPORT Model Organism
"The EDA-EDAR system is an important effector of canonical Wnt signalling in developing skin appendages. It functions by stimulating NF-κB-mediated transcription of effectors or inhibitors of the Wnt, Sonic hedgehog (SHH), fibroblast growth factor (FGF) and transforming growth factor beta (TGFβ)..."
Defines the downstream transcriptional pathways perturbed by reduced EDA-EDAR signaling, based primarily on model-organism studies.
Failed Ectodermal Placode Formation
Reduced EDA-EDAR-NF-kappaB activity impairs induction of ectodermal placodes, the focal epithelial thickenings that initiate hair follicles, teeth, and sweat glands. The resulting epithelial-mesenchymal developmental program is therefore not properly specified.
surface ectodermal cell CL:0000114 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves surface ectodermal cell (CL:0000114). CL:0000114 is a cell type from the Cell Ontology.
ectodermal placode formation GO:0060788 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased ectodermal placode formation (GO:0060788). GO:0060788 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (1 reference)
PMID:24508088 SUPPORT Model Organism
"The TNF family ligand ectodysplasin A (EDA) regulates the induction, morphogenesis and/or maintenance of skin-derived structures such as teeth, hair, sweat glands and several other glands."
Supports EDA-dependent induction and morphogenesis of the appendage primordia.
Ectodermal Appendage Morphogenesis Failure
Failed placode-dependent morphogenesis produces the shared developmental abnormalities of eccrine sweat glands, hair follicles, and teeth that underlie the classic XLHED triad.
sweat gland development GO:0060792 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased sweat gland development (GO:0060792). GO:0060792 is a biological process from the Gene Ontology. ↓ DECREASED hair follicle development GO:0001942 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased hair follicle development (GO:0001942). GO:0001942 is a biological process from the Gene Ontology. ↓ DECREASED odontogenesis of dentin-containing tooth GO:0042475 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased odontogenesis of dentin-containing tooth (GO:0042475). GO:0042475 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (1 reference)
PMID:22421994 SUPPORT Human Clinical
"Hypohidrotic ectodermal dysplasia (HED) is a type of genodermatosis characterized by the abnormal development of sweat glands, teeth, and hair."
Establishes the conserved appendage-development triad in HED.
Eccrine Sweat Gland Aplasia/Hypoplasia
Deficient EDA signaling during embryogenesis impairs eccrine sweat-gland development. Affected males may have no detectable sweat pores or only a few pores, with absent or markedly reduced inducible sweating.
eccrine cell CL:0000434 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves eccrine cell (CL:0000434). CL:0000434 is a cell type from the Cell Ontology.
sweat gland development GO:0060792 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased sweat gland development (GO:0060792). GO:0060792 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (2 references)
PMID:29694819 SUPPORT Human Clinical
"Genetic deficiency of ectodysplasin A (EDA) causes X-linked hypohidrotic ectodermal dysplasia (XLHED), in which the development of sweat glands is irreversibly impaired, an condition that can lead to life-threatening hyperthermia."
Establishes that EDA deficiency irreversibly impairs sweat gland development, causing life-threatening hyperthermia.
PMID:21357618 SUPPORT Human Clinical
"Among 31 XLHED males, 14 had neither detectable sweat pores nor inducible sweating, 10 showed a few sweat pores but absent sweating, and 7 produced reduced sweat volumes (1-11 μl) as compared with controls (38-93 μl)."
Quantifies absent sweat pores, absent inducible sweating, and residual sweat production in genotyped males with XLHED.
Hair Follicle Developmental Failure
Deficient EDA/EDAR signaling impairs hair follicle initiation and development, resulting in sparse, thin, lightly pigmented, and slowly growing scalp and body hair.
hair follicle development GO:0001942 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased hair follicle development (GO:0001942). GO:0001942 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (1 reference)
PMID:24508088 SUPPORT Model Organism
"The TNF family ligand ectodysplasin A (EDA) regulates the induction, morphogenesis and/or maintenance of skin-derived structures such as teeth, hair, sweat glands and several other glands."
Confirms EDA role in development of hair and other skin-derived structures, established primarily in animal models.
Tooth Developmental Defects
Deficient EDA signaling disrupts tooth morphogenesis, causing congenital absence of teeth and abnormal shape of erupted teeth.
odontogenesis of dentin-containing tooth GO:0042475 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased odontogenesis of dentin-containing tooth (GO:0042475). GO:0042475 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (1 reference)
PMID:22421994 SUPPORT Human Clinical
"Hypohidrotic ectodermal dysplasia (HED) is a type of genodermatosis characterized by the abnormal development of sweat glands, teeth, and hair."
Confirms dental abnormalities as a key feature of HED.
Secretory Gland Developmental Dysfunction
EDA regulates several skin-derived glands in addition to eccrine sweat glands. XLHED is associated with dry eyes, crusted secretions, nasal congestion, and airway infections, but the relative contributions of abnormal gland development, altered secretions, and other airway factors are not fully resolved.
gland development GO:0048732 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased gland development (GO:0048732). GO:0048732 is a biological process from the Gene Ontology. ↓ DECREASED
Show evidence (3 references)
PMID:24508088 SUPPORT Model Organism
"The TNF family ligand ectodysplasin A (EDA) regulates the induction, morphogenesis and/or maintenance of skin-derived structures such as teeth, hair, sweat glands and several other glands."
Supports an EDA-dependent developmental role in glands beyond eccrine sweat glands.
PMID:24664614 SUPPORT Human Clinical
"the registry dataset confirmed a spectrum of life-long XLHED clinical complications including recurrent sinus infections (49% males, 52% females), nasal congestion often foul smelling and interfering with feeding (73% males, 27% females)"
Registry data document respiratory and nasal complications without proving a single structural mechanism.
PMID:24508088 SUPPORT Human Clinical
"This syndrome is characterized by the absence or malformation of several skin-derived appendages resulting in hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes, susceptibility to airways infections and crusting of various secretions."
Describes the dry-eye, secretion-crusting, and airway-infection phenotype associated with EDA-pathway deficiency.
Hyperthermia Risk
The absence of functional eccrine sweat glands renders affected individuals unable to dissipate heat through evaporative cooling. This creates a risk of life-threatening hyperthermia, especially during febrile illness, exercise, or hot weather. Unexplained fevers in infancy may be the presenting sign.
Show evidence (2 references)
PMID:24928340 SUPPORT Human Clinical
"In humans, HED is a life-threatening condition in particular in infants due to absent or severely reduced sweating leading to hyperthermia."
Confirms the life-threatening nature of hyperthermia in HED, especially in infants.
PMID:24678015 SUPPORT Human Clinical
"In the first years of life, XLHED-affected patients are at risk for life-threatening hyperthermia and pulmonary infection."
Confirms hyperthermia risk is greatest in early childhood.

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for X-linked Hypohidrotic Ectodermal Dysplasia Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.

Phenotypes

12
Cardiovascular 1
Dry Eyes Keratoconjunctivitis sicca HP:0001097 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Keratoconjunctivitis sicca (HP:0001097). HP:0001097 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24508088 SUPPORT Human Clinical
"hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes, susceptibility to airways infections and crusting of various secretions."
Dry eyes listed as a recognized feature of HED.
Head and Neck 2
Hypodontia FREQUENT HP:0000668 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Hypodontia (HP:0000668). HP:0000668 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24664614 SUPPORT Human Clinical
"XLHED is diagnosed by the triad of decreased sweating, reduced hair, and hypodontia (present in 89%, 74%, and 74% of XLHED respondents)."
Registry data showing hypodontia in 74% of respondents.
Nasal Congestion HP:0001742 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Nasal congestion (HP:0001742). HP:0001742 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24664614 SUPPORT Human Clinical
"nasal congestion often foul smelling and interfering with feeding (73% males, 27% females)"
Registry data quantifying nasal congestion frequency in XLHED.
Immune 2
Recurrent Respiratory Infections FREQUENT HP:0002205 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Recurrent respiratory infections (HP:0002205). HP:0002205 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:24664614 SUPPORT Human Clinical
"the registry dataset confirmed a spectrum of life-long XLHED clinical complications including recurrent sinus infections (49% males, 52% females), nasal congestion often foul smelling and interfering with feeding (73% males, 27% females)"
International registry quantifying respiratory complications in XLHED.
PMID:24678015 SUPPORT Human Clinical
"In the first years of life, XLHED-affected patients are at risk for life-threatening hyperthermia and pulmonary infection. Survival into childhood and beyond is associated with severe dental abnormalities as well as chronic growth, respiratory, skin, eye, and psychosocial disorders."
Pulmonary infection risk and chronic respiratory disorders are recognized features of XLHED.
Eczematoid Dermatitis FREQUENT HP:0000964 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Eczematoid dermatitis (HP:0000964). HP:0000964 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24664614 SUPPORT Human Clinical
"eczema (66% males, 40% females)"
Registry data quantifying eczema frequency in XLHED.
Integument 3
Hypohidrosis VERY_FREQUENT HP:0000966 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Hypohidrosis (HP:0000966). HP:0000966 is a phenotype from the Human Phenotype Ontology.
Show evidence (3 references)
PMID:24664614 SUPPORT Human Clinical
"XLHED is diagnosed by the triad of decreased sweating, reduced hair, and hypodontia (present in 89%, 74%, and 74% of XLHED respondents)."
International registry data showing decreased sweating in 89% of XLHED respondents.
PMID:19681132 SUPPORT Human Clinical
"Hypohidrotic (anhidrotic) ectodermal dysplasia (HED) is a congenital syndrome characterized by sparse hair, oligodontia, and reduced sweating."
Identifies reduced sweating as one of the three cardinal features of HED.
PMID:20301291 SUPPORT Human Clinical
"Hypohidrotic ectodermal dysplasia (HED) is characterized by hypotrichosis (sparseness of scalp and body hair), hypohidrosis (reduced ability to sweat), and hypodontia (congenital absence of teeth)."
The GeneReviews Clinical Characteristics summary identifies hypohidrosis as one of the three cardinal manifestations of HED.
Sparse Hair FREQUENT HP:0008070 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Sparse hair (HP:0008070). HP:0008070 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:24664614 SUPPORT Human Clinical
"XLHED is diagnosed by the triad of decreased sweating, reduced hair, and hypodontia (present in 89%, 74%, and 74% of XLHED respondents)."
Registry data showing reduced hair in 74% of respondents.
PMID:19681132 SUPPORT Human Clinical
"Hypohidrotic (anhidrotic) ectodermal dysplasia (HED) is a congenital syndrome characterized by sparse hair, oligodontia, and reduced sweating."
Sparse hair is identified as one of the three cardinal features of HED.
Dry Skin HP:0000958 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Dry skin (HP:0000958). HP:0000958 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24508088 SUPPORT Human Clinical
"This syndrome is characterized by the absence or malformation of several skin-derived appendages resulting in hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes"
Dry skin identified as a characteristic feature of HED.
Metabolism 1
Heat Intolerance HP:0002046 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Heat intolerance (HP:0002046). HP:0002046 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24508088 SUPPORT Human Clinical
"This syndrome is characterized by the absence or malformation of several skin-derived appendages resulting in hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes"
Heat intolerance listed as a defining feature of HED.
Respiratory 1
Wheezing FREQUENT HP:0030828 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Wheezing (HP:0030828). HP:0030828 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24664614 SUPPORT Human Clinical
"wheezing (66% males, 45% females)"
Registry data quantifying wheezing frequency in XLHED.
Voice 1
Hoarse Voice HP:0001609 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Hoarse voice (HP:0001609). HP:0001609 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:24664614 SUPPORT Human Clinical
"a hoarse, raspy voice (67% males, 23% females)"
Registry data quantifying hoarse voice frequency in XLHED.
Other 1
Conical Teeth Conical tooth HP:0000698 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Conical tooth (HP:0000698). HP:0000698 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:20301291 SUPPORT Human Clinical
"Early dental treatment; bonding of conical teeth; orthodontics as necessary;"
GeneReviews explicitly addresses conical teeth in the management of HED, corroborating this dental morphology without relying on full-text-only evidence.
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Genetic Associations

1
EDA Pathogenic Variants (Causative)
Gene: EDA hgnc:3157 HUGO Gene Nomenclature Committee (hgnc) Relation: this disease-associated gene is this gene This disease-associated gene is EDA (hgnc:3157). hgnc:3157 is a gene from the HUGO Gene Nomenclature Committee. relationship_type: CAUSATIVE
X-linked
Show evidence (3 references)
PMID:29855039 SUPPORT Human Clinical
"This XL-HED phenotype is associated with mutations in the gene encoding the transmembrane protein ectodysplasin-1 (EDA1), a member of the TNFα-related signaling pathway. The proteins from this pathway are involved in signal transduction from ectoderm to mesenchyme leading to the development of..."
Identifies EDA1 as the causative gene encoding a TNF-family protein essential for ectodermal appendage development.
PMID:20301291 SUPPORT Human Clinical
"Identification of a hemizygous EDA pathogenic variant in an affected male or biallelic EDAR, EDARADD, or WNT10A pathogenic variants in an affected male or female confirms the diagnosis."
GeneReviews distinguishes EDA-confirmed XLHED from phenotypically overlapping HED caused by other genes.
PMID:21357618 SUPPORT Human Clinical
"Among 26 different EDA genotypes, specific mutations were shown to be consistently associated with anhidrosis, implying that systematic mapping of EDA mutations together with the analysis of objective clinical data may help to distinguish functionally crucial mutations from those allowing..."
Demonstrates an allelic severity spectrum in which some EDA mutations abolish sweating and others preserve residual gene-product activity.
Variants (1)
EDA alleles with absent versus residual activity
Genotype-phenotype mapping in molecularly confirmed XLHED distinguishes EDA mutations consistently associated with anhidrosis from mutations that allow residual EDA-product activity and reduced, but detectable, sweating.
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Medical Actions

5
Temperature Control and Hyperthermia Prevention
Action: supportive careNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is supportive care (NCIT:C15747). NCIT:C15747 is a clinical intervention from the NCI Thesaurus. Ontology label: Supportive Care NCIT:C15747
Maintain access to water and a cool environment during hot weather, avoid extreme heat, and teach families to recognize and respond promptly to overheating. These measures are especially important in infancy and childhood.
Mechanism Target:
INHIBITS Hyperthermia Risk — Environmental cooling reduces heat accumulation despite deficient evaporative cooling from sweat.
Target Phenotypes: Heat intolerance HP:0002046 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Heat intolerance (HP:0002046). HP:0002046 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:20301291 SUPPORT Human Clinical
"Access to an adequate water supply and a cool environment during hot weather."
GeneReviews recommends water access and environmental cooling to prevent overheating.
Dental Rehabilitation
Action: Dental ProcedureNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Dental Procedure (NCIT:C38052). NCIT:C38052 is a clinical intervention from the NCI Thesaurus. NCIT:C38052
Begin dental assessment and treatment early. Options include bonding conical teeth, orthodontics, age-appropriate prostheses, and implants in selected older children or adults, with periodic replacement of prostheses as growth proceeds.
Target Phenotypes: Hypodontia HP:0000668 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Hypodontia (HP:0000668). HP:0000668 is a phenotype from the Human Phenotype Ontology. Conical tooth HP:0000698 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Conical tooth (HP:0000698). HP:0000698 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:20301291 SUPPORT Human Clinical
"Early dental treatment; bonding of conical teeth; orthodontics as necessary; dental implants in the anterior portion of the mandibular arch in older children; replacement of dental prostheses as needed, often every 2.5 years; dental implants in adults"
GeneReviews specifies age-spanning restorative, orthodontic, prosthetic, and implant-based dental care.
Skin, Ocular, Nasal, and Respiratory Supportive Care
Action: supportive careNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is supportive care (NCIT:C15747). NCIT:C15747 is a clinical intervention from the NCI Thesaurus. Ontology label: Supportive Care NCIT:C15747
Use emollient and eczema care, lubricating eye drops, ambient humidification to reduce nasal concretions, and standard management of recurrent respiratory infections or asthma with specialist referral when needed.
Target Phenotypes: Dry skin HP:0000958 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Dry skin (HP:0000958). HP:0000958 is a phenotype from the Human Phenotype Ontology. Eczematoid dermatitis HP:0000964 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Eczematoid dermatitis (HP:0000964). HP:0000964 is a phenotype from the Human Phenotype Ontology. Keratoconjunctivitis sicca HP:0001097 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Keratoconjunctivitis sicca (HP:0001097). HP:0001097 is a phenotype from the Human Phenotype Ontology. Nasal congestion HP:0001742 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Nasal congestion (HP:0001742). HP:0001742 is a phenotype from the Human Phenotype Ontology. Recurrent respiratory infections HP:0002205 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Recurrent respiratory infections (HP:0002205). HP:0002205 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:20301291 SUPPORT Human Clinical
"Skin care products for eczema and exposures that exacerbate dry skin."
GeneReviews recommends skin-directed supportive care.
PMID:20301291 SUPPORT Human Clinical
"Prevention of nasal concretions through humidification of ambient air is helpful. Lubrication eye drops. Management of recurrent respiratory infections and asthma per primary care provider with referral to allergist and/or pulmonologist as needed."
GeneReviews specifies nasal, ocular, and respiratory supportive measures.
Prenatal EDA1 Replacement Therapy
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
Investigational intra-amniotic recombinant EDA1 replacement has restored sweat gland development and inducible sweating in a small compassionate-use series. Six prenatally treated boys have been reported, with normal perspiration persisting for six years in the two oldest repeatedly treated participants; this remains an investigational approach under prospective study, not routine standard care.
Mechanism Target:
RESTORES EDA Ligand Deficiency — Recombinant Fc-EDA supplies the missing ligand during the fetal developmental window when ectodermal appendages are being specified.
Show evidence (1 reference)
PMID:37108325 SUPPORT Human Clinical
"We previously treated nine male patients with obvious signs of XLHED with a recombinant EDA1 replacement protein, Fc-EDA, either shortly after birth (n = 3) or by prenatal administration in gestational week 26 and beyond (n = 6)."
Directly identifies Fc-EDA as recombinant replacement of the deficient EDA1 ligand.
Show evidence (2 references)
PMID:29694819 SUPPORT Human Clinical
"We administered this protein intraamniotically to two affected human twins at gestational weeks 26 and 31 and to a single affected human fetus at gestational week 26; the infants, born in week 33 (twins) and week 39 (singleton), were able to sweat normally, and XLHED-related illness had not..."
Landmark NEJM study demonstrating successful prenatal correction of XLHED sweat gland deficiency by intra-amniotic EDA1 replacement.
PMID:37108325 SUPPORT Human Clinical
"prenatal EDA1 replacement resulted in ample sweat gland development and pilocarpine-inducible sweating in all treated subjects, who also attained more permanent teeth than their untreated affected relatives. Normal perspiration has persisted for six years in the two oldest boys treated..."
Long-term follow-up confirming permanent correction of sweating ability after prenatal EDA1 replacement, with additional dental benefit.
Genetic Counseling
Action: Genetic CounselingNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Genetic Counseling (NCIT:C15240). NCIT:C15240 is a clinical intervention from the NCI Thesaurus. NCIT:C15240
Explain X-linked transmission after identifying the familial EDA variant. A heterozygous mother has a 50% chance of transmitting the variant in each pregnancy; sons who inherit it are affected, while daughters who inherit it are heterozygous and may manifest features. An affected father transmits the variant to all daughters and no sons. Prenatal and preimplantation testing are possible once the familial variant is known.
Show evidence (2 references)
PMID:20301291 SUPPORT Human Clinical
"If the mother of a proband is heterozygous for an EDA pathogenic variant, the chance of the mother transmitting it in each pregnancy is 50%. If the father of the proband has an EDA pathogenic variant, he will transmit it to all his daughters and none of his sons. Males who inherit the pathogenic..."
GeneReviews provides the correct per-pregnancy transmission and sex-specific risks.
PMID:20301291 SUPPORT Human Clinical
"Once the EDA, EDAR, EDARADD, or WNT10A pathogenic variant(s) have been identified in an affected family member, prenatal and preimplantation genetic testing for HED are possible."
Supports reproductive testing after molecular identification of the familial variant.
🔬

Diagnosis

4
Clinical Diagnosis After Infancy
Classic HED can usually be recognized after infancy from the combination of deficient sweating, sparse hair, and absent or abnormally shaped teeth.
Diagnostic Procedure NCIT:C18020 NCI Thesaurus (NCIT)
Show evidence (1 reference)
PMID:20301291 SUPPORT Human Clinical
"Classic HED can be diagnosed after infancy based on physical features in most affected individuals."
GeneReviews establishes the usual clinical diagnostic route and its timing.
Phenotype-Guided Molecular Testing and EDA Copy-Number Findings
In a small mixed ectodermal-dysplasia cohort, classic symptoms supported targeted EDA/EDAR sequencing, whereas whole-exome sequencing was considered effective when those symptoms were absent. Copy-number variations occurred in 23.1% (3/13) of EDA-positive cases, showing that the reported EDA-positive molecular findings were not limited to sequence variants. This cohort-specific proportion is not an XLHED population prevalence estimate.
Molecular Analysis NCIT:C19770 NCI Thesaurus (NCIT)
Show evidence (2 references)
PMID:39244550 SUPPORT Human Clinical
"Notably, 23.1% (3/13) of EDA-positive cases exhibited copy number variations."
Demonstrates that EDA-positive findings in this cohort included copy-number variation as well as sequence variants.
PMID:39244550 SUPPORT Human Clinical
"When conducting molecular diagnostics for ED, opting for targeted sequencing of EDA/EDAR mutations is advisable for cases with classical symptoms, while WES is deemed an effective strategy for cases in which these symptoms are absent."
Supports targeted EDA/EDAR testing with classical symptoms and whole-exome sequencing when those symptoms are absent.
Quantitative Sweat-Gland Function Assessment
Pilocarpine-induced sweat volume, palmar sweat-pore density, and basal and stimulated skin conductance can objectively quantify sweat-gland dysfunction. These measurements are useful supportive biomarkers but do not determine the causal gene.
Show evidence (2 references)
PMID:21357618 SUPPORT Human Clinical
"In 36 genotyped XLHED patients and 29 control subjects aged 0-57 years, pilocarpine-induced sweat volume, palmar sweat pore density, and palmar skin conductance before and after stimulation were determined."
Specifies three noninvasive quantitative measures evaluated in genotyped XLHED.
PMID:21357618 SUPPORT Human Clinical
"this study confirmed a consistent, quantifiable defect of sweat gland function in male XLHED subjects as a disease biomarker."
Supports quantitative sweat-gland dysfunction as an objective disease biomarker.
📈

Progression

2
Infancy to childhood recognition
Age: Infancy through childhood
The ectodermal defects are congenital, but the cardinal triad often becomes clinically obvious during childhood. Before families learn temperature-control measures, markedly deficient sweating can cause episodes of hyperthermia.
Show evidence (1 reference)
PMID:20301291 SUPPORT Human Clinical
"The cardinal features of classic HED become obvious during childhood. The scalp hair is thin, lightly pigmented, and slow growing. Sweating, although present, is greatly deficient, leading to episodes of hyperthermia until the affected individual or family acquires experience with environmental..."
GeneReviews describes childhood recognition and the early hyperthermia-prone phase before environmental adaptations are established.
Lifelong complications
Age: Childhood through adulthood
Dental and appendage abnormalities persist, while respiratory, nasal, skin, and voice complications can require continuing supportive care across life.
Show evidence (1 reference)
PMID:24664614 SUPPORT Human Clinical
"the registry dataset confirmed a spectrum of life-long XLHED clinical complications including recurrent sinus infections (49% males, 52% females), nasal congestion often foul smelling and interfering with feeding (73% males, 27% females), eczema (66% males, 40% females), wheezing (66% males, 45%..."
Registry data document persistent multisystem complications across the lifespan and quantify several common manifestations.
📊

Prevalence

1
Denmark, January 1, 2011
Point Prevalence 1.6 per 100,000 1–9 per 100,000
This estimate is restricted to molecularly confirmed XLHED. The broader registry-and-algorithm estimate included clinically diagnosed or possible HED and is not used as an XLHED-specific prevalence rate.
Show evidence (1 reference)
PMID:23416623 SUPPORT Human Clinical
"The prevalence was 21.9 per 100,000 overall and 1.6 per 100,000 when restricting to molecularly-confirmed XLHED cases."
Provides the point-prevalence estimate for molecularly confirmed XLHED in the Danish population.
🔀

Differential Diagnoses

2

Conditions with similar clinical presentations that must be differentiated from X-linked Hypohidrotic Ectodermal Dysplasia:

Autosomal Hypohidrotic Ectodermal Dysplasia
Overlapping Features EDAR-, EDARADD-, and WNT10A-related HED can reproduce the classic hair, sweat, and dental triad and may be clinically indistinguishable from XLHED.
Distinguishing Features
  • Biallelic EDAR, EDARADD, or WNT10A pathogenic variants support autosomal recessive HED rather than EDA-related XLHED.
  • Heterozygous EDAR, EDARADD, or WNT10A variants can establish mild autosomal HED.
  • A pedigree with father-to-son transmission excludes X-linked inheritance.
Show evidence (1 reference)
PMID:20301291 SUPPORT Human Clinical
"Identification of a hemizygous EDA pathogenic variant in an affected male or biallelic EDAR, EDARADD, or WNT10A pathogenic variants in an affected male or female confirms the diagnosis. The diagnosis of mild HED is established in a female by identification of a heterozygous EDA, EDAR, EDARADD,..."
GeneReviews defines the overlapping genetic diagnoses and the variant states that distinguish them.
🔬

Clinical Trials

1
NCT04980638 PHASE_II
Prospective, open-label, genotype-match-controlled, nonrandomized, multicenter international phase 2 trial investigating the efficacy and safety of intra-amniotic ER004 as prenatal treatment for unborn male subjects with XLHED.
Target Phenotypes: Hypohidrosis HP:0000966 Human Phenotype Ontology (HP) Relation: this clinical trial targets this phenotype This clinical trial targets Hypohidrosis (HP:0000966). HP:0000966 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
"This is an open-label, prospective, genotype-match controlled for primary estimand, non randomized, multicenter, international Phase 2 clinical trial designed to investigate the efficacy and safety of ER004 administered intraamniotically as a treatment for unborn XLHED male subjects."
The cached official registry summary supports the trial design, phase, intervention route, study population, and efficacy and safety objectives.
🐁

Animal Models

1
Eda mutation with prenatal exposure to recombinant receptor-binding EDA protein Mouse (Mus musculus)
Eda-mutant mouse fetuses underwent normal development after in-utero exposure to recombinant EDA containing the receptor-binding domain. The rescue supports EDA ligand deficiency as causal and demonstrates a prenatal developmental window for replacement therapy, while not by itself establishing human efficacy or safety.
Prenatal rescue of Eda-associated ectodermal developmental defects
Species
Mouse (Mus musculus)
Genotype
Eda mutation with prenatal exposure to recombinant receptor-binding EDA protein
Genes
EDA hgnc:3157 HUGO Gene Nomenclature Committee (hgnc) Relation: this experimental model concerns this gene This experimental model concerns EDA (hgnc:3157). hgnc:3157 is a gene from the HUGO Gene Nomenclature Committee.
Show evidence (1 reference)
PMID:29694819 SUPPORT Model Organism
"We observed normal development of mouse fetuses with Eda mutations after they had been exposed in utero to a recombinant protein that includes the receptor-binding domain of EDA."
Directly documents prenatal phenotypic rescue in the Eda-mutant mouse model.
{ }

Source YAML

click to show
name: X-linked Hypohidrotic Ectodermal Dysplasia
creation_date: "2026-04-24T00:00:00Z"
description: >-
  X-linked hypohidrotic ectodermal dysplasia (XLHED, Christ-Siemens-Touraine syndrome)
  is an X-linked disorder caused by pathogenic variants in EDA, which encodes the
  TNF-superfamily ligand ectodysplasin A. Deficient EDA-EDAR-EDARADD signaling reduces
  canonical NF-kappaB activation, disrupting ectodermal placode formation and the
  morphogenesis of hair follicles, teeth, eccrine sweat glands, and other secretory glands.
  Affected males typically have the classic triad of hypohidrosis, sparse hair, and
  hypodontia, often with conical teeth. Heterozygous females may show variable, usually
  milder manifestations. Markedly deficient sweating creates a risk of life-threatening
  hyperthermia, particularly in infancy and early childhood. In a Danish population study,
  molecularly confirmed XLHED had a point prevalence of 1.6 per 100,000.
category: Genetic
parents:
- Ectodermal Dysplasia
disease_term:
  preferred_term: X-linked hypohidrotic ectodermal dysplasia
  term:
    id: MONDO:0010585
    label: X-linked hypohidrotic ectodermal dysplasia
references:
- reference: PMID:20301291
  title: Hypohidrotic Ectodermal Dysplasia.
  tags:
  - GeneReviews
- reference: PMID:24664614
  title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
- reference: PMID:23416623
  title: "The prevalence of X-linked hypohidrotic ectodermal dysplasia (XLHED) in Denmark, 1995-2010."
- reference: PMID:21357618
  title: Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
- reference: PMID:39244550
  title: Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in Korea.
- reference: PMID:29694819
  title: Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia.
prevalence:
- population: Denmark, January 1, 2011
  measure_type: POINT_PREVALENCE
  prevalence_class: BAND_1_9_PER_100000
  rate_per_100000: 1.6
  notes: >-
    This estimate is restricted to molecularly confirmed XLHED. The broader
    registry-and-algorithm estimate included clinically diagnosed or possible HED
    and is not used as an XLHED-specific prevalence rate.
  evidence:
  - reference: PMID:23416623
    reference_title: "The prevalence of X-linked hypohidrotic ectodermal dysplasia (XLHED) in Denmark, 1995-2010."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The prevalence was 21.9 per 100,000 overall and 1.6 per 100,000 when
      restricting to molecularly-confirmed XLHED cases.
    explanation: >-
      Provides the point-prevalence estimate for molecularly confirmed XLHED in
      the Danish population.
progression:
- phase: Infancy to childhood recognition
  age_range: Infancy through childhood
  notes: >-
    The ectodermal defects are congenital, but the cardinal triad often becomes
    clinically obvious during childhood. Before families learn temperature-control
    measures, markedly deficient sweating can cause episodes of hyperthermia.
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The cardinal features of classic HED become obvious during childhood. The
      scalp hair is thin, lightly pigmented, and slow growing. Sweating, although
      present, is greatly deficient, leading to episodes of hyperthermia until the
      affected individual or family acquires experience with environmental
      modifications to control temperature.
    explanation: >-
      GeneReviews describes childhood recognition and the early hyperthermia-prone
      phase before environmental adaptations are established.
- phase: Lifelong complications
  age_range: Childhood through adulthood
  notes: >-
    Dental and appendage abnormalities persist, while respiratory, nasal, skin,
    and voice complications can require continuing supportive care across life.
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      the registry dataset confirmed a spectrum of life-long XLHED clinical
      complications including recurrent sinus infections (49% males, 52% females),
      nasal congestion often foul smelling and interfering with feeding (73% males,
      27% females), eczema (66% males, 40% females), wheezing (66% males, 45%
      females), and a hoarse, raspy voice (67% males, 23% females).
    explanation: >-
      Registry data document persistent multisystem complications across the
      lifespan and quantify several common manifestations.
inheritance:
- name: X-linked
  description: >-
    EDA-related HED is inherited in an X-linked manner. Hemizygous males who
    inherit the familial pathogenic variant are affected; heterozygous females
    may manifest ectodermal-dysplasia features.
  inheritance_term:
    preferred_term: X-linked inheritance
    term:
      id: HP:0001417
      label: X-linked inheritance
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      EDA-related HED is inherited in an X-linked manner.
    explanation: >-
      GeneReviews directly establishes the inheritance mode of EDA-related HED.
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      If the mother of a proband is heterozygous for an EDA pathogenic variant,
      the chance of the mother transmitting it in each pregnancy is 50%. If the
      father of the proband has an EDA pathogenic variant, he will transmit it to
      all his daughters and none of his sons. Males who inherit the pathogenic
      variant will be affected; females who inherit the pathogenic variant will
      be heterozygous and may show manifestations of ectodermal dysplasia.
    explanation: >-
      Defines transmission risks and sex-dependent manifestations for X-linked HED.
  - reference: PMID:21357618
    reference_title: Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In all 5 heterozygous females, some sweat was detected, but generally less
      than in female controls.
    explanation: >-
      Objective sweat testing documents manifestations in heterozygous females,
      supporting the broader X-linked term rather than an assertion that female
      heterozygotes are uniformly unaffected.
pathophysiology:
- name: EDA Ligand Deficiency
  description: >-
    Pathogenic EDA variants cause complete or partial deficiency of ectodysplasin
    A1, removing the extracellular ligand that normally activates EDAR during
    ectodermal-appendage development.
  role: trigger
  biological_scale: MOLECULAR
  genes:
  - preferred_term: EDA
    term:
      id: hgnc:3157
      label: EDA
  evidence:
  - reference: PMID:37108325
    reference_title: "A Causal Treatment for X-Linked Hypohidrotic Ectodermal Dysplasia: Long-Term Results of Short-Term Perinatal Ectodysplasin A1 Replacement."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      X-linked hypohidrotic ectodermal dysplasia (XLHED), caused by a genetic
      deficiency of ectodysplasin A1 (EDA1), is a rare developmental disorder of
      ectodermal derivatives such as hair, sweat glands, and teeth.
    explanation: >-
      Directly identifies EDA1 deficiency as the initiating molecular lesion in XLHED.
  downstream:
  - target: EDA-EDAR-EDARADD Canonical NF-kappaB Signaling Failure
    causal_link_type: DIRECT
    evidence:
    - reference: PMID:24070496
      reference_title: "The ectodysplasin pathway: from diseases to adaptations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: >-
        It comprises three main gene products: EDA, a ligand that belongs to the tumor
        necrosis factor (TNF)-α family, EDAR, a receptor related to the TNFα receptors,
        and EDARADD, a specific adaptor. This core pathway relies on downstream NF-κB
        pathway activation to regulate target genes.
      explanation: >-
        Places EDA directly upstream of EDAR, EDARADD, and NF-kappaB activation.
- name: EDA-EDAR-EDARADD Canonical NF-kappaB Signaling Failure
  conforms_to: "eda_edar_nfkb_ectodermal_appendage#EDA-EDAR-EDARADD Canonical NF-kappaB Signaling Failure"
  description: >-
    EDA ligand deficiency prevents effective EDAR activation and EDARADD-dependent
    signaling, reducing canonical NF-kappaB transcriptional activity in developing
    surface ectoderm. This also disrupts downstream Wnt, SHH, FGF, and TGF-beta
    pathway effectors involved in epithelial-mesenchymal interactions.
  role: central_effector
  biological_scale: MOLECULAR
  cell_types:
  - preferred_term: surface ectodermal cell
    term:
      id: CL:0000114
      label: surface ectodermal cell
  - preferred_term: keratinocyte
    term:
      id: CL:0000312
      label: keratinocyte
  biological_processes:
  - preferred_term: canonical NF-kappaB signal transduction
    term:
      id: GO:0007249
      label: canonical NF-kappaB signal transduction
    modifier: DECREASED
  evidence:
  - reference: PMID:24070496
    reference_title: "The ectodysplasin pathway: from diseases to adaptations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      It comprises three main gene products: EDA, a ligand that belongs to the tumor
      necrosis factor (TNF)-α family, EDAR, a receptor related to the TNFα receptors,
      and EDARADD, a specific adaptor. This core pathway relies on downstream NF-κB
      pathway activation to regulate target genes.
    explanation: >-
      Defines the EDA-EDAR-EDARADD cascade and its dependence on NF-kappaB activation.
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      The EDA-EDAR system is an important effector of canonical Wnt signalling in
      developing skin appendages. It functions by stimulating NF-κB-mediated
      transcription of effectors or inhibitors of the Wnt, Sonic hedgehog (SHH),
      fibroblast growth factor (FGF) and transforming growth factor beta (TGFβ)
      pathways that regulate interactions within or between epithelial and mesenchymal
      cells and tissues.
    explanation: >-
      Defines the downstream transcriptional pathways perturbed by reduced EDA-EDAR
      signaling, based primarily on model-organism studies.
  downstream:
  - target: Failed Ectodermal Placode Formation
    causal_link_type: DIRECT
- name: Failed Ectodermal Placode Formation
  conforms_to: "eda_edar_nfkb_ectodermal_appendage#Failed Ectodermal Placode Formation"
  description: >-
    Reduced EDA-EDAR-NF-kappaB activity impairs induction of ectodermal placodes,
    the focal epithelial thickenings that initiate hair follicles, teeth, and sweat
    glands. The resulting epithelial-mesenchymal developmental program is therefore
    not properly specified.
  role: central_effector
  biological_scale: TISSUE
  cell_types:
  - preferred_term: surface ectodermal cell
    term:
      id: CL:0000114
      label: surface ectodermal cell
  biological_processes:
  - preferred_term: ectodermal placode formation
    term:
      id: GO:0060788
      label: ectodermal placode formation
    modifier: DECREASED
  evidence:
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      The TNF family ligand ectodysplasin A (EDA) regulates the induction,
      morphogenesis and/or maintenance of skin-derived structures such as teeth, hair,
      sweat glands and several other glands.
    explanation: >-
      Supports EDA-dependent induction and morphogenesis of the appendage primordia.
  downstream:
  - target: Ectodermal Appendage Morphogenesis Failure
    causal_link_type: DIRECT
- name: Ectodermal Appendage Morphogenesis Failure
  conforms_to: "eda_edar_nfkb_ectodermal_appendage#Ectodermal Appendage Morphogenesis Failure"
  description: >-
    Failed placode-dependent morphogenesis produces the shared developmental
    abnormalities of eccrine sweat glands, hair follicles, and teeth that underlie
    the classic XLHED triad.
  role: consequence
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: sweat gland development
    term:
      id: GO:0060792
      label: sweat gland development
    modifier: DECREASED
  - preferred_term: hair follicle development
    term:
      id: GO:0001942
      label: hair follicle development
    modifier: DECREASED
  - preferred_term: odontogenesis of dentin-containing tooth
    term:
      id: GO:0042475
      label: odontogenesis of dentin-containing tooth
    modifier: DECREASED
  evidence:
  - reference: PMID:22421994
    reference_title: "Orofacial features of hypohidrotic ectodermal dysplasia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Hypohidrotic ectodermal dysplasia (HED) is a type of genodermatosis
      characterized by the abnormal development of sweat glands, teeth, and hair.
    explanation: >-
      Establishes the conserved appendage-development triad in HED.
  downstream:
  - target: Eccrine Sweat Gland Aplasia/Hypoplasia
    causal_link_type: DIRECT
  - target: Hair Follicle Developmental Failure
    causal_link_type: DIRECT
  - target: Tooth Developmental Defects
    causal_link_type: DIRECT
  - target: Secretory Gland Developmental Dysfunction
    causal_link_type: DIRECT
- name: Eccrine Sweat Gland Aplasia/Hypoplasia
  description: >-
    Deficient EDA signaling during embryogenesis impairs eccrine sweat-gland
    development. Affected males may have no detectable sweat pores or only a few
    pores, with absent or markedly reduced inducible sweating.
  biological_scale: TISSUE
  cell_types:
  - preferred_term: eccrine cell
    term:
      id: CL:0000434
      label: eccrine cell
  biological_processes:
  - preferred_term: sweat gland development
    term:
      id: GO:0060792
      label: sweat gland development
    modifier: DECREASED
  evidence:
  - reference: PMID:29694819
    reference_title: "Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Genetic deficiency of ectodysplasin A (EDA) causes X-linked hypohidrotic
      ectodermal dysplasia (XLHED), in which the development of sweat glands is
      irreversibly impaired, an condition that can lead to life-threatening hyperthermia.
    explanation: >-
      Establishes that EDA deficiency irreversibly impairs sweat gland development,
      causing life-threatening hyperthermia.
  - reference: PMID:21357618
    reference_title: Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Among 31 XLHED males, 14 had neither detectable sweat pores nor inducible
      sweating, 10 showed a few sweat pores but absent sweating, and 7 produced
      reduced sweat volumes (1-11 μl) as compared with controls (38-93 μl).
    explanation: >-
      Quantifies absent sweat pores, absent inducible sweating, and residual sweat
      production in genotyped males with XLHED.
  downstream:
  - target: Hypohidrosis
    causal_link_type: DIRECT
  - target: Hyperthermia Risk
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Loss of evaporative cooling because sweating is absent or markedly reduced.
- name: Hair Follicle Developmental Failure
  description: >-
    Deficient EDA/EDAR signaling impairs hair follicle initiation and development,
    resulting in sparse, thin, lightly pigmented, and slowly growing scalp and body hair.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: hair follicle development
    term:
      id: GO:0001942
      label: hair follicle development
    modifier: DECREASED
  evidence:
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      The TNF family ligand ectodysplasin A (EDA) regulates the induction,
      morphogenesis and/or maintenance of skin-derived structures such as teeth,
      hair, sweat glands and several other glands.
    explanation: >-
      Confirms EDA role in development of hair and other skin-derived structures,
      established primarily in animal models.
  downstream:
  - target: Sparse Hair
    causal_link_type: DIRECT
- name: Tooth Developmental Defects
  description: >-
    Deficient EDA signaling disrupts tooth morphogenesis, causing congenital absence
    of teeth and abnormal shape of erupted teeth.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: odontogenesis of dentin-containing tooth
    term:
      id: GO:0042475
      label: odontogenesis of dentin-containing tooth
    modifier: DECREASED
  evidence:
  - reference: PMID:22421994
    reference_title: "Orofacial features of hypohidrotic ectodermal dysplasia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Hypohidrotic ectodermal dysplasia (HED) is a type of genodermatosis
      characterized by the abnormal development of sweat glands, teeth, and hair.
    explanation: >-
      Confirms dental abnormalities as a key feature of HED.
  downstream:
  - target: Hypodontia
    causal_link_type: DIRECT
  - target: Conical Teeth
    causal_link_type: DIRECT
- name: Secretory Gland Developmental Dysfunction
  description: >-
    EDA regulates several skin-derived glands in addition to eccrine sweat glands.
    XLHED is associated with dry eyes, crusted secretions, nasal congestion, and
    airway infections, but the relative contributions of abnormal gland development,
    altered secretions, and other airway factors are not fully resolved.
  biological_scale: TISSUE
  biological_processes:
  - preferred_term: gland development
    term:
      id: GO:0048732
      label: gland development
    modifier: DECREASED
  downstream:
  - target: Nasal Congestion
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  - target: Wheezing
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  - target: Hoarse Voice
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  - target: Recurrent Respiratory Infections
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  - target: Dry Eyes
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  evidence:
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      The TNF family ligand ectodysplasin A (EDA) regulates the induction,
      morphogenesis and/or maintenance of skin-derived structures such as teeth, hair,
      sweat glands and several other glands.
    explanation: >-
      Supports an EDA-dependent developmental role in glands beyond eccrine sweat glands.
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      the registry dataset confirmed a spectrum of life-long XLHED clinical
      complications including recurrent sinus infections (49% males, 52% females),
      nasal congestion often foul smelling and interfering with feeding (73% males,
      27% females)
    explanation: >-
      Registry data document respiratory and nasal complications without proving a
      single structural mechanism.
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This syndrome is characterized by the absence or malformation of several
      skin-derived appendages resulting in hypotrychosis, hypodontia, heat-intolerance,
      dry skin and dry eyes, susceptibility to airways infections and crusting of
      various secretions.
    explanation: >-
      Describes the dry-eye, secretion-crusting, and airway-infection phenotype
      associated with EDA-pathway deficiency.
- name: Hyperthermia Risk
  description: >-
    The absence of functional eccrine sweat glands renders affected individuals unable to
    dissipate heat through evaporative cooling. This creates a risk of life-threatening
    hyperthermia, especially during febrile illness, exercise, or hot weather. Unexplained
    fevers in infancy may be the presenting sign.
  biological_scale: ORGANISM
  evidence:
  - reference: PMID:24928340
    reference_title: "Ectodysplasin research--where to next?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In humans, HED is a life-threatening condition in particular in infants due to
      absent or severely reduced sweating leading to hyperthermia.
    explanation: >-
      Confirms the life-threatening nature of hyperthermia in HED, especially in infants.
  - reference: PMID:24678015
    reference_title: "Future developments in XLHED treatment approaches."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In the first years of life, XLHED-affected patients are at risk for
      life-threatening hyperthermia and pulmonary infection.
    explanation: >-
      Confirms hyperthermia risk is greatest in early childhood.
  downstream:
  - target: Heat Intolerance
    causal_link_type: DIRECT
phenotypes:
- name: Hypohidrosis
  category: Classic
  description: >-
    Reduced or absent sweating due to aplasia or severe hypoplasia of eccrine sweat glands.
    This is the most clinically significant feature due to associated hyperthermia risk.
    Reported in 89% of XLHED registrants in the EDIR international registry.
  frequency: VERY_FREQUENT
  phenotype_term:
    preferred_term: Hypohidrosis
    term:
      id: HP:0000966
      label: Hypohidrosis
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      XLHED is diagnosed by the triad of decreased sweating, reduced hair, and
      hypodontia (present in 89%, 74%, and 74% of XLHED respondents).
    explanation: >-
      International registry data showing decreased sweating in 89% of XLHED respondents.
  - reference: PMID:19681132
    reference_title: "Molecular aspects of hypohidrotic ectodermal dysplasia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Hypohidrotic (anhidrotic) ectodermal dysplasia (HED) is a congenital syndrome
      characterized by sparse hair, oligodontia, and reduced sweating.
    explanation: >-
      Identifies reduced sweating as one of the three cardinal features of HED.
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Hypohidrotic ectodermal dysplasia (HED) is characterized by hypotrichosis
      (sparseness of scalp and body hair), hypohidrosis (reduced ability to sweat),
      and hypodontia (congenital absence of teeth).
    explanation: >-
      The GeneReviews Clinical Characteristics summary identifies hypohidrosis as
      one of the three cardinal manifestations of HED.
- name: Sparse Hair
  category: Classic
  description: >-
    Thin, sparse, light-colored scalp hair with reduced hair follicle density. Body hair
    is similarly sparse or absent. Reported in 74% of XLHED registrants.
  frequency: FREQUENT
  phenotype_term:
    preferred_term: Sparse hair
    term:
      id: HP:0008070
      label: Sparse hair
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      XLHED is diagnosed by the triad of decreased sweating, reduced hair, and
      hypodontia (present in 89%, 74%, and 74% of XLHED respondents).
    explanation: >-
      Registry data showing reduced hair in 74% of respondents.
  - reference: PMID:19681132
    reference_title: "Molecular aspects of hypohidrotic ectodermal dysplasia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Hypohidrotic (anhidrotic) ectodermal dysplasia (HED) is a congenital syndrome
      characterized by sparse hair, oligodontia, and reduced sweating.
    explanation: >-
      Sparse hair is identified as one of the three cardinal features of HED.
- name: Hypodontia
  category: Classic
  description: >-
    Congenital absence of one or more teeth. Erupted teeth may be few, abnormally
    shaped, and delayed. Hypodontia was reported in 74% of XLHED registry respondents.
  frequency: FREQUENT
  phenotype_term:
    preferred_term: Hypodontia
    term:
      id: HP:0000668
      label: Hypodontia
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      XLHED is diagnosed by the triad of decreased sweating, reduced hair, and
      hypodontia (present in 89%, 74%, and 74% of XLHED respondents).
    explanation: >-
      Registry data showing hypodontia in 74% of respondents.
- name: Conical Teeth
  category: Classic
  description: >-
    Remaining teeth may have a characteristic conical morphology.
  phenotype_term:
    preferred_term: Conical tooth
    term:
      id: HP:0000698
      label: Conical tooth
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Early dental treatment; bonding of conical teeth; orthodontics as necessary;
    explanation: >-
      GeneReviews explicitly addresses conical teeth in the management of HED,
      corroborating this dental morphology without relying on full-text-only evidence.
- name: Heat Intolerance
  category: Classic
  description: >-
    Inability to tolerate warm environments due to defective thermoregulation
    from absent eccrine glands. Can lead to life-threatening hyperthermia.
  phenotype_term:
    preferred_term: Heat intolerance
    term:
      id: HP:0002046
      label: Heat intolerance
  evidence:
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This syndrome is characterized by the absence or malformation of several
      skin-derived appendages resulting in hypotrychosis, hypodontia,
      heat-intolerance, dry skin and dry eyes
    explanation: >-
      Heat intolerance listed as a defining feature of HED.
- name: Nasal Congestion
  category: Respiratory
  description: >-
    Chronic nasal congestion, often foul smelling and interfering with feeding in
    infancy, was reported in 73% of males and 27% of females in the EDIR registry.
  phenotype_term:
    preferred_term: Nasal congestion
    term:
      id: HP:0001742
      label: Nasal congestion
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      nasal congestion often foul smelling and interfering with feeding (73% males,
      27% females)
    explanation: >-
      Registry data quantifying nasal congestion frequency in XLHED.
- name: Wheezing
  category: Respiratory
  description: >-
    Recurrent wheezing was reported in 66% of males and 45% of females in the
    EDIR registry; both estimates fall in the frequent range.
  frequency: FREQUENT
  phenotype_term:
    preferred_term: Wheezing
    term:
      id: HP:0030828
      label: Wheezing
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      wheezing (66% males, 45% females)
    explanation: >-
      Registry data quantifying wheezing frequency in XLHED.
- name: Hoarse Voice
  category: Respiratory
  description: >-
    A hoarse or raspy voice was reported in 67% of males and 23% of females in
    the EDIR registry, so a single sex-agnostic frequency band is not assigned.
  phenotype_term:
    preferred_term: Hoarse voice
    term:
      id: HP:0001609
      label: Hoarse voice
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      a hoarse, raspy voice (67% males, 23% females)
    explanation: >-
      Registry data quantifying hoarse voice frequency in XLHED.
- name: Dry Skin
  category: Dermatologic
  description: >-
    Xerosis is a recognized HED manifestation.
  phenotype_term:
    preferred_term: Dry skin
    term:
      id: HP:0000958
      label: Dry skin
  evidence:
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This syndrome is characterized by the absence or malformation of several
      skin-derived appendages resulting in hypotrychosis, hypodontia,
      heat-intolerance, dry skin and dry eyes
    explanation: >-
      Dry skin identified as a characteristic feature of HED.
- name: Recurrent Respiratory Infections
  category: Respiratory
  description: >-
    Recurrent sinus infections were reported in 49% of males and 52% of females
    in the EDIR registry. Pulmonary infection is an important risk in early life,
    although the mechanism is likely multifactorial.
  frequency: FREQUENT
  phenotype_term:
    preferred_term: Recurrent respiratory infections
    term:
      id: HP:0002205
      label: Recurrent respiratory infections
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      the registry dataset confirmed a spectrum of life-long XLHED clinical
      complications including recurrent sinus infections (49% males, 52% females),
      nasal congestion often foul smelling and interfering with feeding (73% males,
      27% females)
    explanation: >-
      International registry quantifying respiratory complications in XLHED.
  - reference: PMID:24678015
    reference_title: "Future developments in XLHED treatment approaches."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In the first years of life, XLHED-affected patients are at risk for
      life-threatening hyperthermia and pulmonary infection. Survival into childhood
      and beyond is associated with severe dental abnormalities as well as chronic
      growth, respiratory, skin, eye, and psychosocial disorders.
    explanation: >-
      Pulmonary infection risk and chronic respiratory disorders are recognized
      features of XLHED.
- name: Eczematoid Dermatitis
  category: Dermatologic
  description: >-
    Eczema or atopic dermatitis can occur and was reported in 66% of males and
    40% of females in the international XLHED registry.
  frequency: FREQUENT
  phenotype_term:
    preferred_term: Eczematoid dermatitis
    term:
      id: HP:0000964
      label: Eczematoid dermatitis
  evidence:
  - reference: PMID:24664614
    reference_title: "X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      eczema (66% males, 40% females)
    explanation: >-
      Registry data quantifying eczema frequency in XLHED.
- name: Dry Eyes
  category: Ophthalmologic
  description: >-
    Dry-eye symptoms are a recognized manifestation of EDA-pathway HED.
  phenotype_term:
    preferred_term: Keratoconjunctivitis sicca
    term:
      id: HP:0001097
      label: Keratoconjunctivitis sicca
  evidence:
  - reference: PMID:24508088
    reference_title: "Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes,
      susceptibility to airways infections and crusting of various secretions.
    explanation: >-
      Dry eyes listed as a recognized feature of HED.
genetic:
- name: EDA Pathogenic Variants
  gene_term:
    preferred_term: EDA
    term:
      id: hgnc:3157
      label: EDA
  association: Causative
  relationship_type: CAUSATIVE
  inheritance:
  - name: X-linked
    inheritance_term:
      preferred_term: X-linked inheritance
      term:
        id: HP:0001417
        label: X-linked inheritance
  notes: >-
    Identification of a hemizygous pathogenic EDA variant confirms XLHED in an
    affected male. Heterozygous females can have manifestations. EDA alleles differ
    functionally: some genotypes are consistently associated with anhidrosis, whereas
    others retain enough EDA activity to permit measurable sweating. The entry does
    not assign variant-class frequencies because broad HED cohorts include genetically
    distinct EDAR- and EDARADD-related disease.
  variants:
  - name: EDA alleles with absent versus residual activity
    description: >-
      Genotype-phenotype mapping in molecularly confirmed XLHED distinguishes EDA
      mutations consistently associated with anhidrosis from mutations that allow
      residual EDA-product activity and reduced, but detectable, sweating.
  evidence:
  - reference: PMID:29855039
    reference_title: "Hypohidrotic ectodermal dysplasia: clinical and molecular review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This XL-HED phenotype is associated with mutations in the gene encoding the
      transmembrane protein ectodysplasin-1 (EDA1), a member of the TNFα-related
      signaling pathway. The proteins from this pathway are involved in signal
      transduction from ectoderm to mesenchyme leading to the development of
      ectoderm-derived structures in the fetus such as hair, teeth, skin, nails, and
      eccrine sweat glands.
    explanation: >-
      Identifies EDA1 as the causative gene encoding a TNF-family protein essential
      for ectodermal appendage development.
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Identification of a hemizygous EDA pathogenic variant in an affected male or
      biallelic EDAR, EDARADD, or WNT10A pathogenic variants in an affected male or
      female confirms the diagnosis.
    explanation: >-
      GeneReviews distinguishes EDA-confirmed XLHED from phenotypically overlapping
      HED caused by other genes.
  - reference: PMID:21357618
    reference_title: Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Among 26 different EDA genotypes, specific mutations were shown to be
      consistently associated with anhidrosis, implying that systematic mapping of
      EDA mutations together with the analysis of objective clinical data may help
      to distinguish functionally crucial mutations from those allowing residual
      activity of the gene product.
    explanation: >-
      Demonstrates an allelic severity spectrum in which some EDA mutations abolish
      sweating and others preserve residual gene-product activity.
treatments:
- name: Temperature Control and Hyperthermia Prevention
  description: >-
    Maintain access to water and a cool environment during hot weather, avoid
    extreme heat, and teach families to recognize and respond promptly to
    overheating. These measures are especially important in infancy and childhood.
  therapeutic_modality: BEHAVIORAL
  treatment_term:
    preferred_term: supportive care
    term:
      id: NCIT:C15747
      label: Supportive Care
  target_phenotypes:
  - preferred_term: Heat intolerance
    term:
      id: HP:0002046
      label: Heat intolerance
  target_mechanisms:
  - target: Hyperthermia Risk
    treatment_effect: INHIBITS
    description: >-
      Environmental cooling reduces heat accumulation despite deficient evaporative
      cooling from sweat.
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Access to an adequate water supply and a cool environment during hot weather.
    explanation: >-
      GeneReviews recommends water access and environmental cooling to prevent overheating.
- name: Dental Rehabilitation
  description: >-
    Begin dental assessment and treatment early. Options include bonding conical
    teeth, orthodontics, age-appropriate prostheses, and implants in selected older
    children or adults, with periodic replacement of prostheses as growth proceeds.
  treatment_term:
    preferred_term: Dental Procedure
    term:
      id: NCIT:C38052
      label: Dental Procedure
  target_phenotypes:
  - preferred_term: Hypodontia
    term:
      id: HP:0000668
      label: Hypodontia
  - preferred_term: Conical tooth
    term:
      id: HP:0000698
      label: Conical tooth
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Early dental treatment; bonding of conical teeth; orthodontics as necessary;
      dental implants in the anterior portion of the mandibular arch in older
      children; replacement of dental prostheses as needed, often every 2.5 years;
      dental implants in adults
    explanation: >-
      GeneReviews specifies age-spanning restorative, orthodontic, prosthetic, and
      implant-based dental care.
- name: Skin, Ocular, Nasal, and Respiratory Supportive Care
  description: >-
    Use emollient and eczema care, lubricating eye drops, ambient humidification to
    reduce nasal concretions, and standard management of recurrent respiratory
    infections or asthma with specialist referral when needed.
  treatment_term:
    preferred_term: supportive care
    term:
      id: NCIT:C15747
      label: Supportive Care
  target_phenotypes:
  - preferred_term: Dry skin
    term:
      id: HP:0000958
      label: Dry skin
  - preferred_term: Eczematoid dermatitis
    term:
      id: HP:0000964
      label: Eczematoid dermatitis
  - preferred_term: Keratoconjunctivitis sicca
    term:
      id: HP:0001097
      label: Keratoconjunctivitis sicca
  - preferred_term: Nasal congestion
    term:
      id: HP:0001742
      label: Nasal congestion
  - preferred_term: Recurrent respiratory infections
    term:
      id: HP:0002205
      label: Recurrent respiratory infections
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Skin care products for eczema and exposures that exacerbate dry skin.
    explanation: >-
      GeneReviews recommends skin-directed supportive care.
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Prevention of nasal concretions through humidification of ambient air is
      helpful. Lubrication eye drops. Management of recurrent respiratory infections
      and asthma per primary care provider with referral to allergist and/or
      pulmonologist as needed.
    explanation: >-
      GeneReviews specifies nasal, ocular, and respiratory supportive measures.
- name: Prenatal EDA1 Replacement Therapy
  description: >-
    Investigational intra-amniotic recombinant EDA1 replacement has restored sweat
    gland development and inducible sweating in a small compassionate-use series.
    Six prenatally treated boys have been reported, with normal perspiration persisting
    for six years in the two oldest repeatedly treated participants; this remains an
    investigational approach under prospective study, not routine standard care.
  therapeutic_modality: PROTEIN_REPLACEMENT
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
  target_mechanisms:
  - target: EDA Ligand Deficiency
    treatment_effect: RESTORES
    description: >-
      Recombinant Fc-EDA supplies the missing ligand during the fetal developmental
      window when ectodermal appendages are being specified.
    evidence:
    - reference: PMID:37108325
      reference_title: "A Causal Treatment for X-Linked Hypohidrotic Ectodermal Dysplasia: Long-Term Results of Short-Term Perinatal Ectodysplasin A1 Replacement."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        We previously treated nine male patients with obvious signs of XLHED with a
        recombinant EDA1 replacement protein, Fc-EDA, either shortly after birth (n =
        3) or by prenatal administration in gestational week 26 and beyond (n = 6).
      explanation: >-
        Directly identifies Fc-EDA as recombinant replacement of the deficient EDA1 ligand.
  evidence:
  - reference: PMID:29694819
    reference_title: "Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We administered this protein intraamniotically to two affected human twins
      at gestational weeks 26 and 31 and to a single affected human fetus at
      gestational week 26; the infants, born in week 33 (twins) and week 39
      (singleton), were able to sweat normally, and XLHED-related illness had not
      developed by 14 to 22 months of age.
    explanation: >-
      Landmark NEJM study demonstrating successful prenatal correction of XLHED
      sweat gland deficiency by intra-amniotic EDA1 replacement.
  - reference: PMID:37108325
    reference_title: "A Causal Treatment for X-Linked Hypohidrotic Ectodermal Dysplasia: Long-Term Results of Short-Term Perinatal Ectodysplasin A1 Replacement."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      prenatal EDA1 replacement resulted in ample sweat gland development and
      pilocarpine-inducible sweating in all treated subjects, who also attained more
      permanent teeth than their untreated affected relatives. Normal perspiration
      has persisted for six years in the two oldest boys treated repeatedly with
      Fc-EDA in utero.
    explanation: >-
      Long-term follow-up confirming permanent correction of sweating ability
      after prenatal EDA1 replacement, with additional dental benefit.
  notes: >-
    Evidence is limited to small nonrandomized treated cohorts. The 2023 follow-up
    reports patent holdings and research funding related to the intervention.
- name: Genetic Counseling
  description: >-
    Explain X-linked transmission after identifying the familial EDA variant. A
    heterozygous mother has a 50% chance of transmitting the variant in each
    pregnancy; sons who inherit it are affected, while daughters who inherit it are
    heterozygous and may manifest features. An affected father transmits the variant
    to all daughters and no sons. Prenatal and preimplantation testing are possible
    once the familial variant is known.
  treatment_term:
    preferred_term: Genetic Counseling
    term:
      id: NCIT:C15240
      label: Genetic Counseling
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      If the mother of a proband is heterozygous for an EDA pathogenic variant,
      the chance of the mother transmitting it in each pregnancy is 50%. If the
      father of the proband has an EDA pathogenic variant, he will transmit it to
      all his daughters and none of his sons. Males who inherit the pathogenic
      variant will be affected; females who inherit the pathogenic variant will be
      heterozygous and may show manifestations of ectodermal dysplasia.
    explanation: >-
      GeneReviews provides the correct per-pregnancy transmission and sex-specific risks.
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Once the EDA, EDAR, EDARADD, or WNT10A pathogenic variant(s) have been
      identified in an affected family member, prenatal and preimplantation genetic
      testing for HED are possible.
    explanation: >-
      Supports reproductive testing after molecular identification of the familial variant.
diagnosis:
- name: Clinical Diagnosis After Infancy
  description: >-
    Classic HED can usually be recognized after infancy from the combination of
    deficient sweating, sparse hair, and absent or abnormally shaped teeth.
  diagnosis_term:
    preferred_term: Diagnostic Procedure
    term:
      id: NCIT:C18020
      label: Diagnostic Procedure
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Classic HED can be diagnosed after infancy based on physical features in most
      affected individuals.
    explanation: >-
      GeneReviews establishes the usual clinical diagnostic route and its timing.
- name: Molecular Confirmation of EDA-Related XLHED
  description: >-
    Identification of a hemizygous pathogenic EDA variant confirms XLHED in an
    affected male and distinguishes it from phenotypically overlapping HED caused
    by EDAR, EDARADD, or WNT10A.
  diagnosis_term:
    preferred_term: Molecular Analysis
    term:
      id: NCIT:C19770
      label: Molecular Analysis
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Identification of a hemizygous EDA pathogenic variant in an affected male or
      biallelic EDAR, EDARADD, or WNT10A pathogenic variants in an affected male or
      female confirms the diagnosis.
    explanation: >-
      Defines the molecular confirmation criterion and the major alternative genes.
- name: Phenotype-Guided Molecular Testing and EDA Copy-Number Findings
  description: >-
    In a small mixed ectodermal-dysplasia cohort, classic symptoms supported targeted
    EDA/EDAR sequencing, whereas whole-exome sequencing was considered effective when
    those symptoms were absent. Copy-number variations occurred in 23.1% (3/13) of
    EDA-positive cases, showing that the reported EDA-positive molecular findings were
    not limited to sequence variants. This cohort-specific proportion is not an XLHED
    population prevalence estimate.
  diagnosis_term:
    preferred_term: Molecular Analysis
    term:
      id: NCIT:C19770
      label: Molecular Analysis
  evidence:
  - reference: PMID:39244550
    reference_title: Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in Korea.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Notably, 23.1% (3/13) of EDA-positive cases exhibited copy number variations.
    explanation: >-
      Demonstrates that EDA-positive findings in this cohort included copy-number
      variation as well as sequence variants.
  - reference: PMID:39244550
    reference_title: Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in Korea.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      When conducting molecular diagnostics for ED, opting for targeted sequencing
      of EDA/EDAR mutations is advisable for cases with classical symptoms, while WES
      is deemed an effective strategy for cases in which these symptoms are absent.
    explanation: >-
      Supports targeted EDA/EDAR testing with classical symptoms and whole-exome
      sequencing when those symptoms are absent.
- name: Quantitative Sweat-Gland Function Assessment
  description: >-
    Pilocarpine-induced sweat volume, palmar sweat-pore density, and basal and
    stimulated skin conductance can objectively quantify sweat-gland dysfunction.
    These measurements are useful supportive biomarkers but do not determine the
    causal gene.
  evidence:
  - reference: PMID:21357618
    reference_title: Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In 36 genotyped XLHED patients and 29 control subjects aged 0-57 years,
      pilocarpine-induced sweat volume, palmar sweat pore density, and palmar skin
      conductance before and after stimulation were determined.
    explanation: >-
      Specifies three noninvasive quantitative measures evaluated in genotyped XLHED.
  - reference: PMID:21357618
    reference_title: Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      this study confirmed a consistent, quantifiable defect of sweat gland function
      in male XLHED subjects as a disease biomarker.
    explanation: >-
      Supports quantitative sweat-gland dysfunction as an objective disease biomarker.
differential_diagnoses:
- name: Autosomal Hypohidrotic Ectodermal Dysplasia
  description: >-
    EDAR-, EDARADD-, and WNT10A-related HED can reproduce the classic hair, sweat,
    and dental triad and may be clinically indistinguishable from XLHED.
  distinguishing_features:
  - Biallelic EDAR, EDARADD, or WNT10A pathogenic variants support autosomal recessive HED rather than EDA-related XLHED.
  - Heterozygous EDAR, EDARADD, or WNT10A variants can establish mild autosomal HED.
  - A pedigree with father-to-son transmission excludes X-linked inheritance.
  evidence:
  - reference: PMID:20301291
    reference_title: Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Identification of a hemizygous EDA pathogenic variant in an affected male or
      biallelic EDAR, EDARADD, or WNT10A pathogenic variants in an affected male or
      female confirms the diagnosis. The diagnosis of mild HED is established in a
      female by identification of a heterozygous EDA, EDAR, EDARADD, or WNT10A
      pathogenic variant. The diagnosis of mild HED is established in a male by
      identification of a heterozygous EDAR, EDARADD, or WNT10A pathogenic variant.
    explanation: >-
      GeneReviews defines the overlapping genetic diagnoses and the variant states
      that distinguish them.
- name: IKBKG-Related Immunodeficiency With or Without Ectodermal Dysplasia
  disease_term:
    preferred_term: IKBKG-related immunodeficiency with or without ectodermal dysplasia
    term:
      id: MONDO:0100162
      label: IKBKG-related immunodeficiency with or without ectodermal dysplasia
  description: >-
    Hypomorphic IKBKG (NEMO) variants can cause an X-linked ectodermal-dysplasia
    phenotype through impaired NF-kappaB signaling, overlapping XLHED clinically
    and mechanistically, but with clinically important immunodeficiency.
  distinguishing_features:
  - Dysgammaglobulinemia and severe or recurrent infections favor IKBKG-related disease.
  - A pathogenic IKBKG variant, rather than an EDA variant, establishes this diagnosis.
  evidence:
  - reference: PMID:11047757
    reference_title: A novel X-linked disorder of immune deficiency and hypohidrotic ectodermal dysplasia is allelic to incontinentia pigmenti and due to mutations in IKK-gamma (NEMO).
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Affected males manifest dysgammaglobulinemia and, despite therapy, have
      significant morbidity and mortality from recurrent infections.
    explanation: >-
      Identifies the immune phenotype that distinguishes IKBKG-related HED-ID from XLHED.
  - reference: PMID:11047757
    reference_title: A novel X-linked disorder of immune deficiency and hypohidrotic ectodermal dysplasia is allelic to incontinentia pigmenti and due to mutations in IKK-gamma (NEMO).
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The findings define a new X-linked recessive immunodeficiency syndrome,
      distinct from other types of HED and immunodeficiency syndromes.
    explanation: >-
      Establishes HED-ID as a distinct X-linked immunodeficiency syndrome.
animal_models:
- species: Mouse (Mus musculus)
  genotype: Eda mutation with prenatal exposure to recombinant receptor-binding EDA protein
  genes:
  - preferred_term: EDA
    term:
      id: hgnc:3157
      label: EDA
  description: >-
    Eda-mutant mouse fetuses underwent normal development after in-utero exposure
    to recombinant EDA containing the receptor-binding domain. The rescue supports
    EDA ligand deficiency as causal and demonstrates a prenatal developmental window
    for replacement therapy, while not by itself establishing human efficacy or safety.
  associated_phenotypes:
  - Prenatal rescue of Eda-associated ectodermal developmental defects
  evidence:
  - reference: PMID:29694819
    reference_title: Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      We observed normal development of mouse fetuses with Eda mutations after they
      had been exposed in utero to a recombinant protein that includes the
      receptor-binding domain of EDA.
    explanation: >-
      Directly documents prenatal phenotypic rescue in the Eda-mutant mouse model.
clinical_trials:
- name: NCT04980638
  phase: PHASE_II
  description: >-
    Prospective, open-label, genotype-match-controlled, nonrandomized,
    multicenter international phase 2 trial investigating the efficacy and safety
    of intra-amniotic ER004 as prenatal treatment for unborn male subjects with XLHED.
  target_phenotypes:
  - preferred_term: Hypohidrosis
    term:
      id: HP:0000966
      label: Hypohidrosis
  evidence:
  - reference: clinicaltrials:NCT04980638
    reference_title: "A Prospective, Open-label, Genotype-match Controlled, Multicenter Clinical Trial to Investigate the Efficacy and Safety of Intra-amniotic ER004 as a Prenatal Treatment for Male Subjects With XLHED"
    supports: SUPPORT
    snippet: >-
      This is an open-label, prospective, genotype-match controlled for primary
      estimand, non randomized, multicenter, international Phase 2 clinical trial
      designed to investigate the efficacy and safety of ER004 administered
      intraamniotically as a treatment for unborn XLHED male subjects.
    explanation: >-
      The cached official registry summary supports the trial design, phase,
      intervention route, study population, and efficacy and safety objectives.
datasets: []
📚

References & Deep Research

References

6
Hypohidrotic Ectodermal Dysplasia.
No top-level findings curated for this source.
X-linked hypohidrotic ectodermal dysplasia (XLHED): clinical and diagnostic insights from an international patient registry.
No top-level findings curated for this source.
The prevalence of X-linked hypohidrotic ectodermal dysplasia (XLHED) in Denmark, 1995-2010.
No top-level findings curated for this source.
Sweating ability and genotype in individuals with X-linked hypohidrotic ectodermal dysplasia.
No top-level findings curated for this source.
Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in Korea.
No top-level findings curated for this source.
Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia.
No top-level findings curated for this source.

Deep Research

1
Falcon
X-linked Hypohidrotic Ectodermal Dysplasia (XLHED): Disease Characteristics Research Report
Edison Scientific Literature 37 citations 2026-04-24T18:27:25.066888

X-linked Hypohidrotic Ectodermal Dysplasia (XLHED): Disease Characteristics Research Report

Executive summary

X-linked hypohidrotic ectodermal dysplasia (XLHED) is a rare developmental genetic disorder classically defined by the triad of hypotrichosis, hypohidrosis/anhidrosis, and hypodontia/oligodontia, reflecting abnormal formation of ectodermal appendages (hair follicles, eccrine sweat glands, teeth) due to deficiency of ectodysplasin A1 (EDA1) signaling. (aftab2023xlinkedhypohidroticectodermal pages 1-2, callea2022extendedoverviewof pages 2-4)

A key 2024 advance is improved molecular diagnostic strategy evidence supporting phenotype-guided targeted sequencing (EDA/EDAR) for “classical triad” presentations and exome-scale testing for atypical cases, with copy-number variation (CNV) detection as an important contributor to missed diagnoses. (kim2024geneticprofilingand pages 1-2, kim2024geneticprofilingand pages 7-8)

A major translational development is prenatal protein replacement for affected male fetuses using intra-amniotic delivery of an EDA1 replacement (Fc-EDA/EDI200; and a next-generation molecule ER004), with human compassionate-use data showing sustained restoration of sweating and ongoing multicenter trials (EDELIFE, NCT04980638). (schneider2018prenatalcorrectionof pages 3-5, NCT04980638 chunk 1)


1. Disease information

1.1 Concise overview (current understanding)

XLHED is a genetic ectodermal dysplasia in which deficiency of ectodysplasin A (EDA/EDA1) signaling disrupts epithelial–mesenchymal interactions required for appendage development, producing reduced/absent sweat glands (heat intolerance, risk of hyperthermia), sparse hair, and missing/abnormal teeth; additional recurrent respiratory, skin, and ocular complications are common. (aftab2023xlinkedhypohidroticectodermal pages 1-2, fete2014x‐linkedhypohidroticectodermal pages 2-4)

Abstract-supported definition (direct quote): XLHED is “diagnosed by the triad of decreased sweating, reduced hair, and hypodontia.” (fete2014x‐linkedhypohidroticectodermal pages 1-2)

1.2 Key identifiers and synonyms

Disease name Common synonyms / alternative names MONDO OMIM/MIM disease # Causal gene OMIM IDs ICD-10 MeSH mapping noted in ClinicalTrials.gov
X-linked hypohidrotic ectodermal dysplasia (XLHED) Christ-Siemens-Touraine syndrome; X-linked HED; anhidrotic/hypohidrotic ectodermal dysplasia (aftab2023xlinkedhypohidroticectodermal pages 1-2, callea2022extendedoverviewof pages 2-4, fete2014x‐linkedhypohidroticectodermal pages 1-2) MONDO:0010585 / MONDO_0010585 (NCT04980638 chunk 2) MIM/OMIM: 305100 (nguyennielsen2013theprevalenceof pages 1-2, callea2022extendedoverviewof pages 2-4, schneider2018prenatalcorrectionof pages 1-2) EDA: MIM 300451; EDAR: MIM 604095; EDARADD: MIM 606603 (nguyennielsen2013theprevalenceof pages 1-2, callea2022extendedoverviewof pages 2-4) Q82.4 “Ectodermal Dysplasia (Anhidrotic)” used in Danish registry study for clinically diagnosed HED/XLHED ascertainment (nguyennielsen2013theprevalenceof pages 1-2, nguyennielsen2013theprevalenceof pages 2-3) “Ectodermal Dysplasia 1, Anhidrotic” (MeSH D053358) in NCT04980638 / EDELIFE record (NCT04980638 chunk 2)

Table: This table compiles the main nomenclature and database identifiers for X-linked hypohidrotic ectodermal dysplasia, including disease and gene OMIM numbers, MONDO, ICD-10, and MeSH. It is useful for harmonizing disease records across clinical, ontology, and literature sources.

Evidence source type note: identifiers are derived from aggregated disease resources (registry-based epidemiology and patient registries), and trial registries (ClinicalTrials.gov), rather than individual EHR-only sources. (nguyennielsen2013theprevalenceof pages 1-2, fete2014x‐linkedhypohidroticectodermal pages 1-2, NCT04980638 chunk 1)


2. Etiology

2.1 Disease causal factors

Primary cause: pathogenic loss-of-function variants in EDA (ectodysplasin A; EDA1 isoform) causing deficiency of EDA1 signaling, inherited in an X-linked manner in XLHED. (schneider2022ectodermaldysplasiasnew pages 1-2, nguyennielsen2013theprevalenceof pages 1-2)

Related hypohidrotic ectodermal dysplasia genes (non-X-linked forms): EDAR, EDARADD, WNT10A are frequently implicated in hypohidrotic ED broadly (with EDAR/EDARADD capable of dominant or recessive forms; WNT10A often recessive). (aftab2023xlinkedhypohidroticectodermal pages 1-2, kovalskaia2023molecularbasisand pages 1-2)

2.2 Risk factors

The principal risk factor is carriage of a pathogenic EDA variant in a family (X-linked inheritance), with males generally more severely affected and females showing variable expressivity. (aftab2023xlinkedhypohidroticectodermal pages 1-2, fete2014x‐linkedhypohidroticectodermal pages 2-4)

2.3 Protective factors

No specific genetic or environmental protective factors were identified in the retrieved primary sources.

2.4 Gene–environment interactions

Direct gene–environment interaction evidence (formal GxE) was not identified in the retrieved sources. Clinically, environmental heat exposure interacts with anhidrosis to precipitate hyperthermia risk (a clinically important interaction, though not studied as GxE). (schneider2018prenatalcorrectionof pages 1-2, nguyennielsen2013theprevalenceof pages 1-2)


3. Phenotypes

3.1 Core phenotypes, characteristics, and HPO mapping

Below are major phenotypes (symptoms/signs) with suggested HPO terms and evidence.

1) Hypohidrosis/anhidrosis and heat intolerance - Type: clinical sign/functional deficit - Onset: typically infancy/early childhood (early clinical recognition), though diagnosis may be delayed. (nguyennielsen2013theprevalenceof pages 1-2, aftab2023xlinkedhypohidroticectodermal pages 1-2) - Severity: ranges from absent sweating to low residual sweating depending on genotype. (schneider2011sweatingabilityand pages 5-10) - Key complications: life-threatening hyperthermia. (schneider2018prenatalcorrectionof pages 1-2) - Suggested HPO: HP:0000973 (Anhidrosis), HP:0003214 (Hypohidrosis), HP:0002044 (Hyperthermia), HP:0004370 (Heat intolerance) - Quantitative biomarker data (sweat testing): in controls, mean pilocarpine-stimulated sweat volume was 72 µL (range 29–93 µL) and mean sweat pore density 455 pores/cm² (294–900). In XLHED males, 14/31 had no pores/no inducible sweating; 7/31 produced 1–11 µL (low sweating). (schneider2011sweatingabilityand pages 5-10, schneider2011sweatingabilityand pages 1-5)

2) Hypodontia/oligodontia (abnormal or missing teeth) - Type: physical manifestation - Onset: developmental (childhood; detection with tooth development) - Frequency (registry-reported): hypodontia reported in 89% overall of XLHED respondents in EDIR, and in 74% of male XLHED registrants in one registry analysis. (fete2014x‐linkedhypohidroticectodermal pages 1-2) - Suggested HPO: HP:0000668 (Hypodontia), HP:0000674 (Oligodontia), HP:0006480 (Abnormality of dental morphology)

3) Hypotrichosis / sparse scalp hair and eyebrows - Type: physical manifestation - Frequency (registry-reported): reduced hair reported in 74% overall in EDIR and 80% of male XLHED registrants; in females, hair abnormalities still reported by the majority (63% in EDIR). (fete2014x‐linkedhypohidroticectodermal pages 1-2, fete2014x‐linkedhypohidroticectodermal pages 2-4) - Suggested HPO: HP:0001006 (Hypotrichosis), HP:0000535 (Sparse eyebrow)

4) Recurrent respiratory/nasal complications - Type: symptoms/clinical signs - Frequency (international patient registry, males): foul-smelling nasal discharge 67%, infections requiring antibiotics 52%, recurrent pneumonias 19%, wheeze 66%, recurrent sinusitis 49%, raspy/hoarse voice 67%. (fete2014x‐linkedhypohidroticectodermal pages 2-4) - Suggested HPO: HP:0002789 (Recurrent respiratory infections), HP:0001742 (Chronic sinusitis), HP:0002099 (Wheezing), HP:0001609 (Hoarse voice), HP:0011950 (Nasal discharge)

5) Eczema / dry skin - Type: clinical sign - Frequency (EDIR): eczema reported in 66% males and 40% females in registry summary excerpt. (fete2014x‐linkedhypohidroticectodermal pages 1-2) - Suggested HPO: HP:0000964 (Eczema), HP:0000958 (Dry skin)

6) Ocular surface disease / dry eye - Type: symptom/clinical sign - Frequency: “nearly one-third” affected with ocular dry eye in registry excerpt. (fete2014x‐linkedhypohidroticectodermal pages 2-4) - Suggested HPO: HP:0001097 (Dry eye), HP:0000508 (Photophobia) (frequently associated per ocular review context) (callea2022extendedoverviewof pages 2-4)

3.2 Quality-of-life impact

Quality of life is substantially impacted through heat avoidance/thermoregulation constraints, need for long-term dental rehabilitation, recurrent ENT/respiratory issues, and ocular surface disease requiring surveillance and ongoing supportive care. (aftab2023xlinkedhypohidroticectodermal pages 8-9, callea2022extendedoverviewof pages 2-4, fete2014x‐linkedhypohidroticectodermal pages 2-4)


4. Genetic / molecular information

4.1 Causal genes

  • EDA (ectodysplasin A; EDA1 isoform critical): primary XLHED gene. (schneider2022ectodermaldysplasiasnew pages 1-2, nguyennielsen2013theprevalenceof pages 1-2)
  • EDAR / EDARADD: receptors/adaptors in the same pathway; typically relevant to non-X-linked hypohidrotic ED, but central mechanistically. (callea2022extendedoverviewof pages 2-4)

4.2 Pathogenic variants and functional consequences

Variant classes: deletions, nonsense, frameshift, splice-site, and missense variants affecting key functional domains (furin cleavage site, TNF homology domain, collagen-like repeats) correlate with absent versus residual sweating. (schneider2011sweatingabilityand pages 5-10)

Genotype–phenotype mapping (example evidence): missense variants disrupting the furin recognition site (R153C/R155C/R156H) and certain TNF-domain mutations (e.g., Y304C) are linked to anhidrosis, whereas some variants (e.g., V262F, R276C, G299R, R69L) can be associated with residual sweating. (schneider2011sweatingabilityand pages 5-10)

4.3 Penetrance/expressivity and modifiers

Female heterozygotes can have clinically significant symptoms with high variability (variable expressivity). (fete2014x‐linkedhypohidroticectodermal pages 2-4)

Evidence for specific modifier genes was not identified in the retrieved sources; however, the 2024 Korean cohort emphasizes that phenotype (complete triad vs incomplete) strongly predicts detection of EDA/EDAR mutations, suggesting clinical heterogeneity may partly reflect genetic heterogeneity and structural variants (CNVs). (kim2024geneticprofilingand pages 7-8, kim2024geneticprofilingand pages 1-2)

4.4 Epigenetic information

Explicit epigenetic mechanisms for XLHED were not identified in the retrieved sources.

4.5 Chromosomal abnormalities

Large deletions/CNVs affecting EDA contribute to disease and can be missed without CNV-aware analysis (e.g., MLPA/WGS). In the 2024 Korean ED cohort, 23.1% (3/13) of EDA-positive cases had CNVs. (kim2024geneticprofilingand pages 1-2)


5. Environmental information

No specific toxin/lifestyle/infectious causal factors were identified; the disease is primarily genetic. Key environmental management issue is heat exposure, which is clinically dangerous in anhidrotic patients. (schneider2018prenatalcorrectionof pages 1-2)


6. Mechanism / pathophysiology

6.1 Core pathway (causal chain)

1) Upstream trigger: germline pathogenic EDA variant → deficiency of functional EDA1 ligand. (schneider2018prenatalcorrectionof pages 1-2) 2) Signal transduction: EDA1 binds EDAR, recruits EDARADD, and activates a TNF-like signaling cascade culminating in NF-κB activation. (callea2022extendedoverviewof pages 2-4) 3) Developmental consequence: impaired epithelial–mesenchymal signaling in placodes → failed/aborted development of ectodermal appendages (eccrine sweat glands, teeth, hair follicles, meibomian glands). (callea2022extendedoverviewof pages 2-4, schneider2018prenatalcorrectionof pages 1-2) 4) Clinical manifestations: anhidrosis/hypohidrosis → heat intolerance/hyperthermia risk; hypodontia/oligodontia → chewing/speech/esthetic impacts; hypotrichosis; frequent ENT/respiratory problems likely related to glandular/epithelial abnormalities. (fete2014x‐linkedhypohidroticectodermal pages 2-4, schneider2018prenatalcorrectionof pages 1-2)

6.2 Developmental timing (critical window)

Human eccrine sweat gland morphogenesis has a defined fetal window: “key developmental events” occur in gestational weeks 20–30, motivating prenatal replacement therapy to rescue sweat gland formation. (schneider2022ectodermaldysplasiasnew pages 2-4)

6.3 Crosstalk with WNT/β-catenin (emerging mechanistic synthesis)

Mechanistic synthesis from recent literature indicates reciprocal reinforcement between EDA–EDAR–NF-κB signaling and WNT/β-catenin activity during placode development (e.g., Wnt10b as an NF-κB target; Wnt signaling upregulating Edar). This is commonly inferred from mouse developmental and single-cell analyses and provides a plausible mechanism linking EDA deficiency to broader appendage patterning defects. (jakhar2025interplaybetweenedaedar pages 5-7, jakhar2025interplaybetweenedaedar pages 2-4)

6.4 Suggested ontology terms

  • GO biological processes (suggested): ectodermal appendage development; sweat gland development; tooth development; hair follicle development; epithelial–mesenchymal signaling; NF-κB signaling
  • CL cell types (suggested): keratinocyte (epidermal basal keratinocyte); odontogenic epithelial cell; dermal papilla cell; myoepithelial cell (sweat gland)

(These are ontology suggestions aligned with the mechanisms described in the cited sources. (callea2022extendedoverviewof pages 2-4, schneider2022ectodermaldysplasiasnew pages 2-4, jakhar2025interplaybetweenedaedar pages 2-4))


7. Anatomical structures affected

7.1 Organ/tissue targets (with ontology suggestions)

  • Skin (UBERON:0002097) with eccrine sweat glands and hair follicles affected (reduced/absent sweat glands; hypotrichosis). (aftab2023xlinkedhypohidroticectodermal pages 1-2, schneider2022ectodermaldysplasiasnew pages 2-4)
  • Dentition / tooth germs (UBERON:0001759 tooth) with hypodontia/oligodontia. (fete2014x‐linkedhypohidroticectodermal pages 1-2, schneider2018prenatalcorrectionof pages 3-5)
  • Upper airway/nasal structures with chronic nasal discharge/sinusitis and respiratory complications. (fete2014x‐linkedhypohidroticectodermal pages 2-4)
  • Eye and adnexa: meibomian glands and ocular surface impacted (dry eye risk; meibomian gland endpoints included in EDELIFE). (NCT04980638 chunk 1, callea2022extendedoverviewof pages 2-4)

7.2 Subcellular localization

Not specifically addressed in the retrieved sources beyond EDA being a transmembrane TNF-family ligand that is cleaved and released (a secreted signaling moiety). (schneider2022ectodermaldysplasiasnew pages 2-4)


8. Temporal development

8.1 Onset

Clinical manifestations often begin in infancy/early childhood; one clinical summary reports symptom onset between “one month to 23 months.” (aftab2023xlinkedhypohidroticectodermal pages 1-2)

8.2 Progression and course

The disease is lifelong; some severe early-life risks (hyperthermia) can be mitigated with recognition and management. Registry data describe “life-long XLHED clinical complications” such as sinus infections, eczema, wheezing, and hoarse voice. (fete2014x‐linkedhypohidroticectodermal pages 1-2)


9. Inheritance and population

9.1 Inheritance

Predominantly X-linked (males more severely affected; females variably affected). (aftab2023xlinkedhypohidroticectodermal pages 1-2, fete2014x‐linkedhypohidroticectodermal pages 2-4)

9.2 Epidemiology (recent statistics from studies)

  • Denmark (nationwide registry ascertainment, prevalence as of Jan 1, 2011): prevalence 1.6 per 100,000 for molecularly confirmed XLHED; broader HED/possible HED ascertainment yielded higher cumulative prevalence estimates (all categories 21.9 per 100,000). The study used ICD-10 Q82.4 for clinically diagnosed cases and confirmed XLHED by EDA mutation. (nguyennielsen2013theprevalenceof pages 1-2, nguyennielsen2013theprevalenceof pages 2-3)

Expert interpretation: the very large difference between molecularly confirmed prevalence and broader algorithm-defined HED prevalence implies substantial under-confirmation (genetic testing gaps) and/or misclassification when relying on administrative codes alone, supporting current emphasis on molecular confirmation and CNV-aware testing. (nguyennielsen2013theprevalenceof pages 1-2, kim2024geneticprofilingand pages 1-2)


10. Diagnostics

10.1 Clinical recognition

Diagnosis is often based on the triad (sweat, hair, teeth) and characteristic facies/complications. (fete2014x‐linkedhypohidroticectodermal pages 1-2, aftab2023xlinkedhypohidroticectodermal pages 1-2)

10.2 Functional sweating tests (quantitative biomarker)

Pilocarpine-induced sweat testing plus sweat pore density assessment is a quantifiable biomarker approach. - In Schneider et al. (2011), sweat pore count sensitivity for identifying affected males was 94% in children and 92% in adults, with clear quantitative separation from controls. (schneider2011sweatingabilityand pages 5-10) - Controls showed mean sweat volume 72 µL and mean sweat pore density 455 pores/cm², whereas many XLHED males had absent pores and 0 sweat, and low-sweating males produced 1–11 µL. (schneider2011sweatingabilityand pages 5-10, schneider2011sweatingabilityand pages 1-5)

10.3 Genetic testing approaches (2024 evidence-based strategy)

2024 cohort evidence (Korea, Orphanet J Rare Dis; published 2024-09-?? per journal issue metadata): - Overall diagnostic yield: 74.1% (20/27) mutation-positive. (kim2024geneticprofilingand pages 1-2) - Among positives, 80% (16/20) had EDA or EDAR mutations; 23.1% (3/13) of EDA-positive cases had CNVs. (kim2024geneticprofilingand pages 1-2) - Phenotype predicts yield: 94.1% of patients with the complete triad (hair/skin/dental) had detectable EDA/EDAR mutations, vs 0% when those three symptoms were not all present. (kim2024geneticprofilingand pages 7-8, kim2024geneticprofilingand pages 1-2)

Direct abstract quote (diagnostic strategy conclusion): “When conducting molecular diagnostics for ED, opting for targeted sequencing of EDA/EDAR mutations is advisable for cases with classical symptoms, while WES is deemed an effective strategy for cases in which these symptoms are absent.” (kim2024geneticprofilingand pages 1-2)

10.4 Prenatal diagnosis (emerging real-world implementation)

Prenatal ultrasound-based tooth germ counting can support non-invasive fetal assessment in at-risk pregnancies; this approach is used in trial screening and was part of the diagnostic workup for prenatal therapy. (schneider2022ectodermaldysplasiasnew pages 1-2, schneider2018prenatalcorrectionof pages 1-2)

10.5 Differential diagnosis

A case-based review highlights the need to distinguish XLHED from other ectodermal dysplasias and syndromes (e.g., EEC syndrome) and acquired hypohidrosis causes, emphasizing clinical and molecular confirmation. (aftab2023xlinkedhypohidroticectodermal pages 8-9)


11. Outcome / prognosis

11.1 Key risks and complications

  • Hyperthermia risk in infancy/childhood due to inability to sweat is emphasized as potentially life-threatening. (schneider2018prenatalcorrectionof pages 1-2, nguyennielsen2013theprevalenceof pages 1-2)
  • Chronic ENT/respiratory morbidity is common (registry-based frequencies summarized above). (fete2014x‐linkedhypohidroticectodermal pages 2-4)

11.2 Registry-based mortality signal

In EDIR registry analysis, 21% of XLHED registrants reported a family history of infant or childhood deaths, stated as consistent with published mortality data. (fete2014x‐linkedhypohidroticectodermal pages 1-2)


12. Treatment

12.1 Supportive and multidisciplinary care (current standard)

Current routine care is largely supportive and preventive, including thermoregulation/heat avoidance strategies, dental rehabilitation (prosthodontics/implants), dermatologic management (eczema/dry skin), ENT/pulmonary management for recurrent infections, and ophthalmic care for dry eye/ocular surface disease. (aftab2023xlinkedhypohidroticectodermal pages 8-9, callea2022extendedoverviewof pages 2-4)

Suggested MAXO terms (examples): supportive care; dental prosthesis placement; management of hyperthermia; skin emollient therapy; artificial tears / ocular surface lubrication; respiratory infection prevention.

12.2 Advanced therapeutics: EDA1 protein replacement

12.2.1 Prenatal intra-amniotic Fc-EDA (EDI200) – human compassionate-use evidence

Schneider et al. (NEJM, 2018-04-26) reported intra-amniotic administration of Fc-EDA (EDI200) to 3 affected male fetuses. - Dosing (twins): 100 mg/kg estimated fetal body weight at gestational week 26 and again at week 31. (schneider2018prenatalcorrectionof pages 3-5) - Evidence of fetal uptake: cord-blood Fc-EDA measurable 7 days after administration (62.4 and 932 ng/mL). (schneider2018prenatalcorrectionof pages 3-5) - Efficacy endpoints: treated infants had normal sweat-duct density and “normal pilocarpine-induced sweating at 6 months,” with no hyperthermic episodes or respiratory-related hospitalizations over 22 months in the twin case. (schneider2018prenatalcorrectionof pages 3-5) - Quote (author conclusion): “Prenatal treatment with Fc-EDA restored sustained sweating ability in human patients with EDA mutations that abrogate perspiration.” (schneider2018prenatalcorrectionof pages 5-7)

Visual evidence: Figure 1 from the NEJM report shows the contrast between untreated XLHED (no sweat pores/0 µL sweat) and treated infant vs healthy control for sweat pores and sweat volume outcomes. (schneider2018prenatalcorrectionof media 9c02cda0)

12.2.2 Postnatal Fc-EDA trials (limited efficacy window)

A translational review notes that postnatal dosing in infants did not successfully induce sweat ducts or sweating, consistent with a restricted developmental window for eccrine gland morphogenesis. (schneider2022ectodermaldysplasiasnew pages 2-4)

12.2.3 ER004 (prenatal intra-amniotic EDELIFE trial; ongoing)

ClinicalTrials.gov describes ER004 as an “EDA1 replacement” designed for high-affinity EDAR binding. - Design: Phase 2, open-label, genotype-match controlled; 3 intra-amniotic injections ~3 weeks apart starting gestational week 26 at 100 mg/kg estimated fetal weight per injection. (NCT04980638 chunk 1) - Primary endpoint: mean sweat volume at 6 months (pilocarpine-induced). (NCT04980638 chunk 1) - Secondary endpoints include: sweat pore density, dental development, meibomian glands, ocular outcomes, hospitalizations for hyperthermia/infections. (NCT04980638 chunk 1)

Expert analysis: the trial’s inclusion of objective sweating endpoints (sweat volume and pore density) and longer follow-up (to age 5) directly addresses prior limitations of early small compassionate-use series and aligns with validated sweat biomarkers (pilocarpine iontophoresis, pore counts) used in genotype–phenotype work. (NCT04980638 chunk 1, schneider2011sweatingabilityand pages 5-10)


13. Prevention

13.1 Primary prevention

No primary prevention exists for germline XLHED beyond reproductive options.

13.2 Secondary/tertiary prevention (complication avoidance)

Key complication prevention includes early diagnosis, anticipatory guidance for fever/heat exposure, and early dental/ENT/ophthalmic interventions to prevent downstream morbidity. (aftab2023xlinkedhypohidroticectodermal pages 8-9, callea2022extendedoverviewof pages 2-4)

13.3 Genetic counseling and reproductive options

Given X-linked inheritance and severe male phenotype, cascade testing and counseling are central. Prenatal ultrasound screening (tooth germ assessment) is used clinically and in trial screening as a non-invasive diagnostic tool in at-risk pregnancies. (schneider2022ectodermaldysplasiasnew pages 1-2, schneider2018prenatalcorrectionof pages 1-2)


14. Other species / natural disease

Naturally occurring EDA-related hypohidrotic ectodermal dysplasia has been reported across species, supporting conserved biology. - Cat (first report, 2024-06): a male cat with alopecia and tooth anomalies had a hemizygous EDA missense variant; the paper notes EDA loss-of-function variants cause HED in humans, mice, dogs, and cattle and extends this to cats. (rietmann2024edamissensevariant pages 1-2) - Cattle (historic): evidence cited for bovine anhidrotic ED caused by deletion of exon 3 of the bovine ED1 gene (EDA ortholog). (rietmann2024edamissensevariant pages 2-4)

NCBI Taxonomy identifiers were not provided in the retrieved excerpts.


15. Model organisms

15.1 Tabby mouse (murine Eda model)

The Tabby mouse is a canonical model of EDA deficiency used to study ectodermal appendage development and therapeutic rescue by prenatal EDA replacement; mechanistic work in the NEJM report also used Eda-deficient mice to show neonatal Fc receptor–dependent fetal uptake after intra-amniotic therapy. (schneider2018prenatalcorrectionof pages 2-3, schneider2018prenatalcorrectionof pages 3-5)

15.2 Translational large-animal models

Dog models of XLHED have been used for prenatal recombinant EDA1 administration, with improvements reported across multiple ectodermal structures, supporting translational relevance to prenatal therapy. (aftab2023xlinkedhypohidroticectodermal pages 8-9)


Notes on evidence gaps

  • Orphanet identifiers, ICD-11, and MeSH terms beyond those in ClinicalTrials.gov were not directly extractable from the retrieved texts.
  • PMIDs were not present in the excerpts provided for most papers (NEJM/Orphanet/Cureus); therefore, this report cites DOIs/URLs and publication month/year as available in-source.

Key sources (with URLs and dates)

  • Schneider H. Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia. N Engl J Med. 2018-04-26. https://doi.org/10.1056/NEJMoa1714322 (schneider2018prenatalcorrectionof pages 1-2, schneider2018prenatalcorrectionof pages 3-5)
  • Kim MJ et al. Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in Korea. Orphanet J Rare Dis. 2024 (volume 19:329; published 2024). https://doi.org/10.1186/s13023-024-03331-6 (kim2024geneticprofilingand pages 1-2)
  • Nguyen-Nielsen M et al. The prevalence of XLHED in Denmark, 1995–2010. Eur J Med Genet. 2013-05. https://doi.org/10.1016/j.ejmg.2013.01.012 (nguyennielsen2013theprevalenceof pages 1-2)
  • Fete M et al. XLHED: Clinical and diagnostic insights from an international patient registry. Am J Med Genet A. 2014-10. https://doi.org/10.1002/ajmg.a.36436 (fete2014x‐linkedhypohidroticectodermal pages 1-2)
  • ClinicalTrials.gov. EDELIFE: Intraamniotic Administrations of ER004… NCT04980638. Updated 2025-04-30. https://clinicaltrials.gov/study/NCT04980638 (NCT04980638 chunk 1)
  • Schneider H et al. Sweating ability and genotype in individuals with XLHED. J Med Genet. 2011-02. https://doi.org/10.1136/jmg.2010.084012 (schneider2011sweatingabilityand pages 5-10)

References

  1. (aftab2023xlinkedhypohidroticectodermal pages 1-2): Hammad Aftab, Ivan A Escudero, and Fatin Sahhar. X-linked hypohidrotic ectodermal dysplasia (xlhed): a case report and overview of the diagnosis and multidisciplinary modality treatments. Cureus, Jun 2023. URL: https://doi.org/10.7759/cureus.40383, doi:10.7759/cureus.40383. This article has 10 citations.

  2. (callea2022extendedoverviewof pages 2-4): Michele Callea, Stefano Bignotti, Francesco Semeraro, Francisco Cammarata-Scalisi, Jinia El-Feghaly, Antonino Morabito, Vito Romano, and Colin E. Willoughby. Extended overview of ocular phenotype with recent advances in hypohidrotic ectodermal dysplasia. Children, 9:1357, Sep 2022. URL: https://doi.org/10.3390/children9091357, doi:10.3390/children9091357. This article has 9 citations.

  3. (kim2024geneticprofilingand pages 1-2): Man Jin Kim, Jee-Soo Lee, Seung Won Chae, Sung Im Cho, Jangsup Moon, Jung Min Ko, Jong-Hee Chae, and Moon-Woo Seong. Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in korea. Orphanet Journal of Rare Diseases, Sep 2024. URL: https://doi.org/10.1186/s13023-024-03331-6, doi:10.1186/s13023-024-03331-6. This article has 1 citations and is from a peer-reviewed journal.

  4. (kim2024geneticprofilingand pages 7-8): Man Jin Kim, Jee-Soo Lee, Seung Won Chae, Sung Im Cho, Jangsup Moon, Jung Min Ko, Jong-Hee Chae, and Moon-Woo Seong. Genetic profiling and diagnostic strategies for patients with ectodermal dysplasias in korea. Orphanet Journal of Rare Diseases, Sep 2024. URL: https://doi.org/10.1186/s13023-024-03331-6, doi:10.1186/s13023-024-03331-6. This article has 1 citations and is from a peer-reviewed journal.

  5. (schneider2018prenatalcorrectionof pages 3-5): Holm Schneider, Florian Faschingbauer, Sonia Schuepbach-Mallepell, Iris Körber, Sigrun Wohlfart, Angela Dick, Mandy Wahlbuhl, Christine Kowalczyk-Quintas, Michele Vigolo, Neil Kirby, Corinna Tannert, Oliver Rompel, Wolfgang Rascher, Matthias W. Beckmann, and Pascal Schneider. Prenatal correction of x-linked hypohidrotic ectodermal dysplasia. New England Journal of Medicine, 378:1604-1610, Apr 2018. URL: https://doi.org/10.1056/nejmoa1714322, doi:10.1056/nejmoa1714322. This article has 219 citations and is from a highest quality peer-reviewed journal.

  6. (NCT04980638 chunk 1): Intraamniotic Administrations of ER004 to Male Subjects With X-linked Hypohidrotic Ectodermal Dysplasia. EspeRare Foundation. 2022. ClinicalTrials.gov Identifier: NCT04980638

  7. (fete2014x‐linkedhypohidroticectodermal pages 2-4): Mary Fete, Julie Hermann, Jeffrey Behrens, and Kenneth M. Huttner. X‐linked hypohidrotic ectodermal dysplasia (xlhed): clinical and diagnostic insights from an international patient registry. American Journal of Medical Genetics Part A, 164:2437-2442, Oct 2014. URL: https://doi.org/10.1002/ajmg.a.36436, doi:10.1002/ajmg.a.36436. This article has 72 citations.

  8. (fete2014x‐linkedhypohidroticectodermal pages 1-2): Mary Fete, Julie Hermann, Jeffrey Behrens, and Kenneth M. Huttner. X‐linked hypohidrotic ectodermal dysplasia (xlhed): clinical and diagnostic insights from an international patient registry. American Journal of Medical Genetics Part A, 164:2437-2442, Oct 2014. URL: https://doi.org/10.1002/ajmg.a.36436, doi:10.1002/ajmg.a.36436. This article has 72 citations.

  9. (NCT04980638 chunk 2): Intraamniotic Administrations of ER004 to Male Subjects With X-linked Hypohidrotic Ectodermal Dysplasia. EspeRare Foundation. 2022. ClinicalTrials.gov Identifier: NCT04980638

  10. (nguyennielsen2013theprevalenceof pages 1-2): Mary Nguyen-Nielsen, Stine Skovbo, Dea Svaneby, Lars Pedersen, and Jon Fryzek. The prevalence of x-linked hypohidrotic ectodermal dysplasia (xlhed) in denmark, 1995-2010. European journal of medical genetics, 56 5:236-42, May 2013. URL: https://doi.org/10.1016/j.ejmg.2013.01.012, doi:10.1016/j.ejmg.2013.01.012. This article has 97 citations and is from a peer-reviewed journal.

  11. (schneider2018prenatalcorrectionof pages 1-2): Holm Schneider, Florian Faschingbauer, Sonia Schuepbach-Mallepell, Iris Körber, Sigrun Wohlfart, Angela Dick, Mandy Wahlbuhl, Christine Kowalczyk-Quintas, Michele Vigolo, Neil Kirby, Corinna Tannert, Oliver Rompel, Wolfgang Rascher, Matthias W. Beckmann, and Pascal Schneider. Prenatal correction of x-linked hypohidrotic ectodermal dysplasia. New England Journal of Medicine, 378:1604-1610, Apr 2018. URL: https://doi.org/10.1056/nejmoa1714322, doi:10.1056/nejmoa1714322. This article has 219 citations and is from a highest quality peer-reviewed journal.

  12. (nguyennielsen2013theprevalenceof pages 2-3): Mary Nguyen-Nielsen, Stine Skovbo, Dea Svaneby, Lars Pedersen, and Jon Fryzek. The prevalence of x-linked hypohidrotic ectodermal dysplasia (xlhed) in denmark, 1995-2010. European journal of medical genetics, 56 5:236-42, May 2013. URL: https://doi.org/10.1016/j.ejmg.2013.01.012, doi:10.1016/j.ejmg.2013.01.012. This article has 97 citations and is from a peer-reviewed journal.

  13. (schneider2022ectodermaldysplasiasnew pages 1-2): Holm Schneider. Ectodermal dysplasias: new perspectives on the treatment of so far immedicable genetic disorders. Frontiers in Genetics, Sep 2022. URL: https://doi.org/10.3389/fgene.2022.1000744, doi:10.3389/fgene.2022.1000744. This article has 27 citations and is from a peer-reviewed journal.

  14. (kovalskaia2023molecularbasisand pages 1-2): V. A. Kovalskaia, T. Cherevatova, A. V. Polyakov, and O. P. Ryzhkova. Molecular basis and genetics of hypohidrotic ectodermal dysplasias. Vavilov Journal of Genetics and Breeding, 27:676-683, Nov 2023. URL: https://doi.org/10.18699/vjgb-23-78, doi:10.18699/vjgb-23-78. This article has 6 citations.

  15. (schneider2011sweatingabilityand pages 5-10): Holm Schneider, Johanna Hammersen, Sabine Preisler-Adams, Kenneth Huttner, Wolfgang Rascher, and Axel Bohring. Sweating ability and genotype in individuals with x-linked hypohidrotic ectodermal dysplasia. Journal of Medical Genetics, 48:426-432, Feb 2011. URL: https://doi.org/10.1136/jmg.2010.084012, doi:10.1136/jmg.2010.084012. This article has 70 citations and is from a domain leading peer-reviewed journal.

  16. (schneider2011sweatingabilityand pages 1-5): Holm Schneider, Johanna Hammersen, Sabine Preisler-Adams, Kenneth Huttner, Wolfgang Rascher, and Axel Bohring. Sweating ability and genotype in individuals with x-linked hypohidrotic ectodermal dysplasia. Journal of Medical Genetics, 48:426-432, Feb 2011. URL: https://doi.org/10.1136/jmg.2010.084012, doi:10.1136/jmg.2010.084012. This article has 70 citations and is from a domain leading peer-reviewed journal.

  17. (aftab2023xlinkedhypohidroticectodermal pages 8-9): Hammad Aftab, Ivan A Escudero, and Fatin Sahhar. X-linked hypohidrotic ectodermal dysplasia (xlhed): a case report and overview of the diagnosis and multidisciplinary modality treatments. Cureus, Jun 2023. URL: https://doi.org/10.7759/cureus.40383, doi:10.7759/cureus.40383. This article has 10 citations.

  18. (schneider2022ectodermaldysplasiasnew pages 2-4): Holm Schneider. Ectodermal dysplasias: new perspectives on the treatment of so far immedicable genetic disorders. Frontiers in Genetics, Sep 2022. URL: https://doi.org/10.3389/fgene.2022.1000744, doi:10.3389/fgene.2022.1000744. This article has 27 citations and is from a peer-reviewed journal.

  19. (jakhar2025interplaybetweenedaedar pages 5-7): Ajay Jakhar, Konrad Łukaszyk, Anna Pulawska-Czub, and Krzysztof Kobielak. Interplay between eda-edar and wnt signalling pathways in the development of skin appendages in hypohidrotic ectodermal dysplasia. Pediatria i Medycyna Rodzinna, 21:51-58, Apr 2025. URL: https://doi.org/10.15557/pimr.2025.0006, doi:10.15557/pimr.2025.0006. This article has 3 citations.

  20. (jakhar2025interplaybetweenedaedar pages 2-4): Ajay Jakhar, Konrad Łukaszyk, Anna Pulawska-Czub, and Krzysztof Kobielak. Interplay between eda-edar and wnt signalling pathways in the development of skin appendages in hypohidrotic ectodermal dysplasia. Pediatria i Medycyna Rodzinna, 21:51-58, Apr 2025. URL: https://doi.org/10.15557/pimr.2025.0006, doi:10.15557/pimr.2025.0006. This article has 3 citations.

  21. (schneider2018prenatalcorrectionof pages 5-7): Holm Schneider, Florian Faschingbauer, Sonia Schuepbach-Mallepell, Iris Körber, Sigrun Wohlfart, Angela Dick, Mandy Wahlbuhl, Christine Kowalczyk-Quintas, Michele Vigolo, Neil Kirby, Corinna Tannert, Oliver Rompel, Wolfgang Rascher, Matthias W. Beckmann, and Pascal Schneider. Prenatal correction of x-linked hypohidrotic ectodermal dysplasia. New England Journal of Medicine, 378:1604-1610, Apr 2018. URL: https://doi.org/10.1056/nejmoa1714322, doi:10.1056/nejmoa1714322. This article has 219 citations and is from a highest quality peer-reviewed journal.

  22. (schneider2018prenatalcorrectionof media 9c02cda0): Holm Schneider, Florian Faschingbauer, Sonia Schuepbach-Mallepell, Iris Körber, Sigrun Wohlfart, Angela Dick, Mandy Wahlbuhl, Christine Kowalczyk-Quintas, Michele Vigolo, Neil Kirby, Corinna Tannert, Oliver Rompel, Wolfgang Rascher, Matthias W. Beckmann, and Pascal Schneider. Prenatal correction of x-linked hypohidrotic ectodermal dysplasia. New England Journal of Medicine, 378:1604-1610, Apr 2018. URL: https://doi.org/10.1056/nejmoa1714322, doi:10.1056/nejmoa1714322. This article has 219 citations and is from a highest quality peer-reviewed journal.

  23. (rietmann2024edamissensevariant pages 1-2): Stefan J. Rietmann, Noëlle Cochet-Faivre, Helene Dropsy, Vidhya Jagannathan, Lucie Chevallier, and Tosso Leeb. Eda missense variant in a cat with x-linked hypohidrotic ectodermal dysplasia. Genes, 15:854, Jun 2024. URL: https://doi.org/10.3390/genes15070854, doi:10.3390/genes15070854. This article has 1 citations.

  24. (rietmann2024edamissensevariant pages 2-4): Stefan J. Rietmann, Noëlle Cochet-Faivre, Helene Dropsy, Vidhya Jagannathan, Lucie Chevallier, and Tosso Leeb. Eda missense variant in a cat with x-linked hypohidrotic ectodermal dysplasia. Genes, 15:854, Jun 2024. URL: https://doi.org/10.3390/genes15070854, doi:10.3390/genes15070854. This article has 1 citations.

  25. (schneider2018prenatalcorrectionof pages 2-3): Holm Schneider, Florian Faschingbauer, Sonia Schuepbach-Mallepell, Iris Körber, Sigrun Wohlfart, Angela Dick, Mandy Wahlbuhl, Christine Kowalczyk-Quintas, Michele Vigolo, Neil Kirby, Corinna Tannert, Oliver Rompel, Wolfgang Rascher, Matthias W. Beckmann, and Pascal Schneider. Prenatal correction of x-linked hypohidrotic ectodermal dysplasia. New England Journal of Medicine, 378:1604-1610, Apr 2018. URL: https://doi.org/10.1056/nejmoa1714322, doi:10.1056/nejmoa1714322. This article has 219 citations and is from a highest quality peer-reviewed journal.