<unk>  <unk>  is an autosomal recessive inherited disorder characterised by brittle hair and intellectual impairment. The word breaks down into tricho – "hair", thio – "sulphur", and dystrophy – "wasting away" or literally "bad nourishment".<unk>  is associated with a range of symptoms connected with organs of the ectoderm and neuroectoderm.<unk>  may be subclassified into four syndromes: Approximately half of all patients with<unk>  have photosensitivity, which divides the classification into syndromes with or without photosensitivity; BIDS and PBIDS, and IBIDS and PIBIDS. Modern covering usage is<unk> -P (photosensitive), and<unk> .
Trichothiodystrophy
Xeroderma pigmentosum
Tardive dysmentia
Fragile X syndrome
Acorea, microphthalmia and cataract syndrome
Fragile X-associated tremor/ataxia syndrome
Huntington's disease-like syndrome
Rett syndrome