Enhanced radiosensitivity and defective DNA repair in cultured fibroblasts derived from Rothmund Thomson syndrome patients.
Rothmund Thomson syndrome (RTS) is an oculocutaneous and cancer-prone disorder in which enhanced carcinogen sensitivity, mediated through abnormal DNa metabolism, may be an associated factor. Cultured fibroblasts from 5 RTS patients have been examined for their colony-forming abilities and DNa repair capacities following gamma-irradiation. 2 of the 4 RTS strains showed enhanced sensitivity following hypoxic gamma-irradiation, and 1 of these 2 strains also showed enhanced sensitivity under toxic conditions. Defective DNA repair was implicated in the above abnormal responses to gamma-radiation since both strains displayed reduced levels of repair synthesis and slow removal of radiogenic DNA lesions (assayed by their sensitivity to strand-incising activities present in protein extracts of Micrococcus luteus cells). A hypothesis is presented to rationalize the origin and heterogeneity of these laboratory phenotypes of RTS.
D000293:Adolescent; D000328:Adult; D002386:Cataract / Q000235:genetics*; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D004260:DNA Repair / Q000528:radiation effects*; D004392:Dwarfism / Q000235:genetics; D005260:Female; D005347:Fibroblasts / Q000528:radiation effects*; D005720:Gamma Rays; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism; D011836:Radiation Tolerance; D012871:Skin Diseases / Q000235:genetics*; D013577:Syndrome
D010100:Oxygen