trichothiodystrophy
Findings
No curated finding names trichothiodystrophy yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Trichothiodystrophy or TTD is a heterogeneous group disorders characterized by short, brittle hair with low-sulphur content (due to an abnormal synthesis of the sulfur containing keratins).
Definition from the Mondo Disease Ontology (MONDO:0018053), read 2026-09-29. CC BY 4.0.
Features
91 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Abnormal pyramidal signHPOHP:0007256
- Occasional (5% to 29% of cases)
- Abnormality of prenatal development or birthHPOHP:0001197
- Occasional (5% to 29% of cases)
- Absence of subcutaneous fatHPOHP:0007485
- Occasional (5% to 29% of cases)
- Alopecia of scalpHPOHP:0002293
- Occasional (5% to 29% of cases)
- AnemiaHPOHP:0001903
- Occasional (5% to 29% of cases)
- Aplasia/Hypoplasia of the nailsHPOHP:0008386
- Occasional (5% to 29% of cases)
- AstigmatismHPOHP:0000483
- Occasional (5% to 29% of cases)
- Bilateral microphthalmosHPOHP:0007633
- Occasional (5% to 29% of cases)
- Bilateral sensorineural hearing impairmentHPOHP:0008619
- Occasional (5% to 29% of cases)
- Bird-like faciesHPOHP:0000320
- Occasional (5% to 29% of cases)
- Brittle hairHPOHP:0002299
- Occasional (5% to 29% of cases)
- BronchoconstrictionHPOHP:4000007
- Occasional (5% to 29% of cases)
Show the remaining 79
- CardiomyopathyHPOHP:0001638
- Occasional (5% to 29% of cases)
- Carious teethHPOHP:0000670
- Occasional (5% to 29% of cases)
- Cerebral cortical atrophyHPOHP:0002120
- Occasional (5% to 29% of cases)
- Cerebral dysmyelinationHPOHP:0007266
- Occasional (5% to 29% of cases)
- ClubbingHPOHP:0001217
- Occasional (5% to 29% of cases)
- Coarse facial featuresHPOHP:0000280
- Occasional (5% to 29% of cases)
Genes
8 genes
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- MARS1HGNC:6898
- Strong · PanelApp Australia · Autosomal recessive · 2025
- ERCC2HGNC:3434
- Supportive · Orphanet · Autosomal recessive · 2021
- ERCC3HGNC:3435
- Supportive · Orphanet · Autosomal recessive · 2021
- GTF2E2HGNC:4651
- Supportive · Orphanet · Autosomal recessive · 2021
- GTF2H5HGNC:21157
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
- A kind of
Other names
1 name
Resolves to: trichothiodystrophy
- Also called
- trichothiodystrophy syndrome