Xeroderma pigmentosum complementation group F in a non-Japanese patient.

Genetic complementation studies allowed assignment of a 22-year-old-white woman to the rare complementation group of classic, excision-defective xeroderma pigmentosum (group F cell strain), previously reported only in patients from Japan. She manifested mild cutaneous changes, with no tumors and normal sensitivity to monochromatic ultraviolet irradiation. Unscheduled deoxyribonucleic acid synthesis in cultured fibroblasts (XP126LO) after irradiation with germicidal ultraviolet light was reduced to 13% of control values during the first 2 hours and rose to 45% of normal by 7 to 8 hours.