An imbalance in sex chromosomes alters cell survival of human skin fibroblasts exposed to ionizing radiation in vitro.

We report that a cell clone with a 45,X(-Y) karyotype, obtained from a male individual who is a gene carrier for hereditary adenomatosis of the colon and rectum (ACR), was considerably more resistent to gamma-ray irradiation (D0 range 184-240) than were diploid ACR skin fibroblasts (SF) obtained from sister biopsies of the same individual or of normal controls (D0 range 90-125). In addition, cell clones obtained from a Turner's syndrome female patient and from a female patient with focal endometrial hyperplasia, each with a 45,X(-X) karyotype, were abnormally resistent to gamma-ray irradiation (D0 range 168-195). These results may suggest an association between the status of the sex chromosomes and an altered response to gamma-ray-induced cytotoxicity of human SF.