• A 31-year-old female patient with xeroderma pigmentosum (XP) XP43KO was assigned to complementation group D by the cell-fusion complementation methods. Cultured XP43KO cells from our patient had the defective DNA repair phenotype showing a residual level of ultraviolet (UV)-induced unscheduled DNA synthesis (45% of normal) and an eightfold higher sensitivity to 254-nm UV killing, compared with normal cells. The phototest on the patient revealed the delayed maximum reaction to UV-B-induced erythema and lower minimal erythema doses at 290- and 300-nm monochromatic wavelengths. However, the XP43K0 patient showed no apparent neurologic abnormalities and rather mild or moderate skin lesions at the age of 31 years, although DNA repair deficiency in XP43K0 cells from our patient fell into the range of group D cells.
(Arch Dermatol 1988;124:256-260)