Chromosomal radiosensitivity of ataxia telangiectasia cells at different cell cycle stages.

X-ray induced chromosomal aberrations in peripheral blood lymphocytes as well as in skin fibroblasts from ataxia telangiectasia patients, and from normal individuals were studied. At all stages of cell cycles-namely G0, G1, and G2, more aberrations were induced in AT cells than in normal cells. In addition, AT cells were sensitive to induction of chromosomal aberrations by tritium beta rays from incorporated radioactive thymidine. Possible reasons for the increased sensitivity of AT cells for induction of chromosomal aberrations by ionizing radiations are discussed.