THE POST-UV COLONY-FORMING ABILITY OF NORMAL FIBROBLAST STRAINS AND OF THE XERODERMA PIGMENTOSUM GROUP-G STRAIN

[摘要] In xeroderma pigmentosum, an inherited disorder of defective DNA repair, post-UV colony-forming ability of fibroblasts from patients in complementation groups A through F correlates with the patients'' neurological status. The 1st xeroderma pigmentosum patient assigned to the recently discovered group G had the neurological abnormalities of XP. The post-UV colony-forming ability of cultured fibroblasts from this patient and from 5 control donors was determined. Log-phase fibroblasts were irradiated with 254 nm UV light from a germicidal lamp, trypsinized and replated at known densities. After 2-4 wk incubation the cells were fixed, stained and scored for colony formation. The strains'' post-UV colony-forming ability curves were obtained by plotting the log of the percent remaining post-UV colony-forming ability as a function of the UV dose. The post-UV colony-forming ability of 2 of the 5 new normal strains was in the previously defined control donor zone but that of the other 3 extended down to the level of the most resistant xeroderma pigmentosum strain. The post-UV colony-forming ability curve of the group G fibroblasts was not significantly different from the curves of the group D fibroblast strains from patients with clinical histories similar to that of the group G patient.