The Observation of γ-RAY Induced DNA Single Strand Ereaks and Their Rejoining in Chinese Hamster Ovary Cells and Human Peripheral Lymphocytes

The induction and rejoining kinetics of DNA single strand breaks in irradiated human peripheral lymphocytes (Do=400 rads) and Chinese hamster ovary cells (CHO)(DO=200 rads)were studied by alkaline elution method.Although the radiosensitivity of these two types of mammalian cells is different,the extent of single strand breakage is approximately the same within the range of 100-3000 rads.The ability to rejoin the single strand breaks in the more radiosensitive CHO cells is greater than that in lymphocytes.It appears that there is no direct relationship between the efficiency of rejoining of sihgle strand break and radiosensitivity in these two types of cells.