title: Hypersensitivity of cells from a new chromosomal-breakage syndrome to DNA-damaging agents.
abstract: Cells derived from a patient with severe chromosomal breakage, immunodeficiency, and growth retardation were found to resemble those from individuals with ataxia telangiectasia (A-T) in terms of their sensitivity to cell killing and the induction of cytogenetic abnormalities by X-rays. Their response to other DNA-damaging agents, including 254-nm UV light, mitomycin C, MNNG, and bleomycin was also A-T-like. In contrast to classical A-T, however, X-irradiated cells exhibited a G1 block after release from density inhibition of growth that was not significantly different from that of normal controls.
mesh_terms: D000328:Adult; D000361:Agammaglobulinemia / Q000235:genetics*; D002453:Cell Cycle / Q000528:radiation effects; D002869:Chromosome Aberrations / Q000235:genetics*; D025063:Chromosome Disorders; D002873:Chromosome Fragility; D004247:DNA / Q000187:drug effects / Q000528:radiation effects*; D004249:DNA Damage; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000528:radiation effects* / Q000648:ultrastructure; D006801:Humans; D008231:Lymphopenia / Q000235:genetics*; D008831:Microcephaly / Q000235:genetics*; D008934:Mitogens / Q000494:pharmacology; D013577:Syndrome
chemical_list: D008934:Mitogens; D004247:DNA