[The analysis of genomic mutations and structural chromosome aberrations in irradiated human lymphocytes]

The lymphocytes of healthy donors were exposed to 60Co gamma-rays in doses ranging 0.5 to 6.0 Gy, and were incubated with PHA and 5-bromodeoxyuridine at 37 degrees C for 72 h. In the course of five consecutive in vitro divisions of cultured lymphocytes, the frequency of polyploid metaphases were determined, and chromosome structural aberrations in polyploid and diploid metaphases were analyzed. Dose dependence of polyploid formation was investigated, and patterns of polyploid cells were analyzed at various DNA replication cycles post exposure and 5-bromodeoxyuridine addition. Radiation is most effective induces of polyploid metaphase of the second and of the third mitotic divisions. In metaphases of the fourth mitotic divisions radiation does not enlarge authentically frequency of polyploid cells. In metaphases of the fifth divisions was not retrieved of polyploid cells. Was shown, that 84.8% of polyploid metaphases compound of tetraploids, while of octoploids and the cells with endoreduplicated chromosomes compound, accordingly, 8.4 and 6.8%. The analysis of chromosome aberrations have shown that the percentage of aberrant cells was higher in polyploid metaphases than in diploids, which indicated that chromosome lesions were involved in formation of polyploid metaphases.