[The effect of Mycoplasma contamination on the karyotypic structure of a skin fibroblast cell line from the Indian muntjac].

The karyotypic variability has been studied in a low chromosomal cell line of the Indian muntjak skin fibroblasts contaminated with Mycoplasma arginini R-16 and Acholeplasma laidlawii A. The mycoplasmal contamination exerted influence on the cell distribution for the chromosome number. The frequency of the modal class cells with 7 chromosomes, having the main structure variant of the karyotype (MSVK) 2 + 2 + 1 + 1 + 1, was seen to decrease, while the frequency of the submodal class cells with 6 chromosomes, having MSVK 2 + 2 + 1 + 1 because of the loss of Y1 chromosome from MSVK 2 + 2 + 1 + 1, to increase. The frequency of chromosomal aberrations, predominantly that of dicentrics, was higher in the contaminated variants. Dicentrics were mainly produced by chromosomes 1 and 2. They were formed by a nonrandom combination of chromosomes and their arms. Possible correlations are discussed between aneuploidy and dicentric chromosome formation in low chromosomal cell lines, and cell adaptations to culture conditions.