Three Cases of Xeroderma Pigmentosum Complementation Group E

Abstract

Three Japanese women (aged 50, 42, 41) with mild symptoms of xeroderma pigmentosum (XP) were assigned to complementation group E (XP80TO, XP81TO, XP82TO) following cell hybridization studies. All showed lowered minimal erythema between those of normal Japanese and the XP group A subjects at wavelengths of 280, 290 and 300 nm of monochromatic ultraviolet (UV) light. The delayed peak reaction of UV erythema was observed in XP80TO and 81TO. All fibroblast strains from these patients had a reduced level of 40∼44% unscheduled DNA synthesis (UDS), after irradiation with 10 J/m² of 254 nm UV. These cells exhibited a higher sensitivity to 254 nm UV killing [n (extrapolation number)=1.3∼1.8, D₀ (mean lethal dose)=2.2∼2.8 J/m²] than did normal cells (n=1.5, D₀ 5.0 J/m²). None of these group E patients have neurological abnormalities. The XP80TO and 81TO subjects had basaliomas on the face at the ages of 46 and 41, respectively.