Trichothiodystrophy

• Pollit 1968
• Allen 1971
• Tay 1971
• Price 1980

Pollit syndrome, sulphur deficiency hair

Due to reduced sulphur content, brittle, brittle, broken hair occurs.

Rare disease.

• AR
• Due to a defect in the DNA excision repair system in sulphur metabolism, there is a low level of sulphur and cystine in the hair of patients with trichothiodystrophy
• Trichothiodystrophy (TTD) is divided into TTD-A, TTD-B and TTD-D depending on 3 gene loci.
• Association:
  • Xeroderma pigmentosum.

• Brittle, brittle hair. In some cases, foci similar to alopecia areata are visible. As with trichorrhexis nodosa, fractures may occur in the hair shaft. Longitudinal fractures (trichoschisis) are also often visible.
• More neuro-ectodermal changes (nail atrophy, koilonychia) may also occur.
• Further symptoms include, dry, ichthyosis-like skin, mental retardation and increased photosensitivity, short stature, cataract.

• Polarisation microscopy: tiger tail pattern= alternating light, then dark bands
• Scanning electron microscopy: cuticle degeneration as well as cortical degradation
• Determination of sulphur (<50%) and cystine (>10%) content in hair or nails

Early death.

No therapy possible.

1. Traboulsi H, Davoli S, Catez P, Egly JM, Compe E. Dynamic partnership between TFIIH, PGC-1α and SIRT1 is impaired in trichothiodystrophy. PLoS Genet. 2014 Oct 23;10(10):e1004732.
2. Atkinson EC, Thiara D, Tamura D, DiGiovanna JJ, Kraemer KH, Hadigan C. Growth and nutrition in children with trichothiodystrophy. J Pediatr Gastroenterol Nutr. 2014 Oct;59(4):458-64.
3. Singh A, Compe E, Le May N, Egly JM. TFIIH subunit alterations causing xeroderma pigmentosum and trichothiodystrophy specifically disturb several steps during transcription. Am J Hum Genet. 2015 Feb 5;96(2):194-207.