[In vitro induction of numerical changes in the karyotype of normal and transformed cells of Dzhungarian and Chinese hamsters].

The comparative study of the frequency of colcemid-induced aneuploidy and polyploidy in cultured normal and transformed cells of Djungarian hamster is described. The occurrence of variants with changed chromosome number is much higher in populations of SV40-transformed cell line (4/21) than in normal embryonic cultures. In transformed lines of Djungarian and Chinese hamsters (4/21 and V-79) the frequency of cells with changed chromosome number was found to be depend on the culture density: the percentage of polyploids was 4-5-fold higher when the number of seeded cells was 2-fold lower. The highest number (18-29%) of hypermodal cells was produced at drug concentrations of 0.02--0.025 mkg/ml. The percentage of polyploids under these conditions reached 10--20. At further increaseof colcemid concentrations the proportion of polyploid cells increased. In Djungarian hamster embryonic cell cultures there were single cells with changed chromosome numbers at a concentrarion of the drug of 0.015-0.1 mkg/ml.