title: The effects of beta-radiation on sister-chromatid exchanges in cultured human lymphocytes.
abstract: The incidence of Sister-Chromatid Exchanges (SCEs) due to beta-radiation was investigated in cultured human lymphocytes using the BrdU/Giemsa technique. Cultures treated continuously with 0.001 and 0.01 microCi of [3H]uridine showed no increase in either chromosome abnormalities or SCEs. Continuous treatment with 0.1 microCi resulted in a significant increase in chromosome aberrations but no increase in SCEs, while treatment with 0.2 microCi gave both an increase in chromosome aberrations and SCEs. Cultures given a 4-h pulse with 1.0 microCi showed a significant increase in both SCEs and chromosome aberrations. The results indicate that low levels of beta-radiation do not cause an increase in SCEs in human lymphocytes, and, that a number, if not all the exchanges observed at low levels of beta-radiation with autoradiography, may be spontaneous events.
mesh_terms: D002478:Cells, Cultured; D002842:Chromatids / Q000528:radiation effects*; D002869:Chromosome Aberrations; D003434:Crossing Over, Genetic; D004583:Electrons; D006801:Humans; D008214:Lymphocytes / Q000648:ultrastructure; D011839:Radiation, Ionizing; D012854:Sister Chromatid Exchange