Abstract
This paper deals with the development of assay systems for radiation-induced mutations to 8-azaguanine (8AG) resistance, using XP2OS cells which belong to complementation group A of xeroderma pigmentosum (XP) and the familiar human cancer HeLa S3 cells. The results indicated that these mutation assay systems to purine analogue resistance using XP2OS and HeLa S3 cells are useful for determining the mutation frequency induced by X-rays and that the data obtained by using these assay systems can be used for predicting the mutation frequency expected after exposure of man to low doses of ionizing radiation. In addition, a plot of induced mutation frequency against log surviving fraction yielded an approximately linear relationship for five cell types including human diploid cells, Chinese hamster cells and mouse lymphoma cells, which have already been studied by other workers. This relationship seems to suggest that mammalian cells generally have the same fixed probability of mutation induction relative to the extent of damage caused by ionizing radiation.
