title: Cellular hypersensitivity to chronic gamma-radiation in cultured fibroblasts from ataxia-telangiectasia heterozygotes.
abstract: Retrospective studies of cancer incidence in AT families suggest that the major detrimental impact of the AT gene on the health of the general population stems from its disease-predisposing potential in heterozygotes. The absence of a definitive marker for routine identification of such carriers, however, has previously precluded direct validation of this predicted effect of AT heterozygosity. We demonstrate that chronic gamma-ray exposure, because it expands the difference in radiation cytotoxicity between normal and heterozygotic strains compared to acute dose delivery, may point the way to development of a reliable laboratory diagnostic procedure for identification of carriers of a defective AT gene.
mesh_terms: D001260:Ataxia Telangiectasia / Q000150:complications / Q000235:genetics*; D002478:Cells, Cultured; D005347:Fibroblasts / Q000528:radiation effects; D006580:Genetic Carrier Screening / Q000379:methods*; D005819:Genetic Markers; D006801:Humans; D009369:Neoplasms / Q000150:complications; D011836:Radiation Tolerance
chemical_list: D005819:Genetic Markers