Comparative studies of chromosome aberrations in G0 and G1 phase Human fibroblast cells exposed to low or High LET radiations

Abstract

We used fluorescence in situ hybridization with whole-chromosome probes for human chromosomes 1 and 3 to investigate the G0 and G1 phase chromosome aberrations after exposure to X-ray, silicon ions and iron ions . Non-dividing fibroblast cells (AG1522) were exposed to low- or high-LET radiations and chromosome aberrations in fusion premature chromosome condensation technique (PCC) after several hours repair (G0) or subcultured immediately after irradiation (G1) were scored. The repair process of chromosome fragments were determinted using the G0/G1 type premature chromosome condensation technique .We have found that chromosomal fragments were rejoined at a similar rate between G0 and G1 phases until 12hrs. However, around two times higher frequency of misrejoining was observed under growing G1 phase for X-rays, while similar frequency of misrejoining was observed after high-LET irradiations.