Sensitivity to UV radiation of fibroblasts from a Japanese group A xeroderma pigmentosum patient with mild neurological abnormalities.

A 12-year-old girl, suffering from xeroderma pigmentosum (XP), had mild cutaneous and neurological abnormalities. She showed no neurological abnormalities at the age of seven, but areflexia of the patellar tendons at II. She had no malignant tumours. The skin fibroblasts from the patient were about twice as sensitive to the lethal effects of 254 nm ultraviolet (UV) radiation as those of Group C XP patients, and about twice as resistant as those of typical Group A XP patients. The ability of these fibroblasts to reactivate UV-damage adenovirus 5 was intermediate between those of Group C and typical Group A patients. The patient's cells were assigned to genetic complementation Group A by use of the cell-fusion technique. This is the first case in Japan of a Group A XP patient with mild neurological abnormalities. The mild cutaneous manifestations of this patient may be explained by the residual ability of the cells to repair UV-damaged DNA.