Abstract
The karyotypes of various HeLa cells, one of the most often used human cell lines, were evaluated using strains maintained at different laboratories. Judging from chromosomal number and rearranged chromosomes, they could be classified into three groups. Group I was composed of the originally established HeLa and Groups II and Ill were composed of cells presumably derived from HeLa S3.O6-Methylguanine-DNA-methyltransferase activity was positive in cell sublines belonging to Groups I and III, but negative in Group II. These findings show that the HeLa cell sublines have distinct enzymatic activities, making it important to identify the cell sublines used in work with HeLa.
