XP: Hypersensitivity of the skin to ultraviolet light-induced freckle-like pigmentation changes. Early onset and hugely increased incidence of skin and ocular cancers (basal cell carcinomas, squamous cell carcinomas and melanoma) on sun-exposed areas. Extreme sunburn sensitivity. Neurological degeneration resulting in sensorineural deafness, ataxia, areflexia, microcephaly and intellectual deficiency.
TTD: Sulphur-deficient brittle hair, ichthyosis, collodion baby, frequent infections, developmental delay, reduced stature, photosensitivity, debilitating hip degeneration, beta-thalassaemia trait.
XPD