CHROMOSOMAL CHARACTERISTIC OF CHINESE-HAMSTER CELLS AND THEIR HGPRT-DEFICIENT MUTANT LINE

Abstract

Chinese hamster cell line (line K 431, HGPRT+ [hypoxanthine-guanine phosphoribosyl transferase]) and its mutant (line K II, HGPRT-) are similar in the numerical composition of the karyotype (modal number 22 chromosomes), but differ in its structural constitution (occurrence of trisomy, breaks in the centromeric region, chromosome losses and others). Deletion and rearrangement of some heterochromatic segments of the X chromosome appeared with a higher frequency in HGPRT- line and can constitute one of the conceivable causes of the HGPRT activity loss in the mutant line.