A Role of DNA Double Strand Break Repair in the Induction of Genetic Instability

Abstract

We previously demonstrated that scid mouse cells were hypersensitive to genetic instability induced by radiation. To confirm this result, we established scid mouse cells expressing human DNA-PKcs by the introduction of a human chromosome 8. The human DNA-PKcs complemented the hypersensitivity to the induction of delayed reproductive death in scid mouse cells, indicating that NHEJ play a role to suppress the induction of genetic instability. To know a role of double strand break repair in the induction of genetic instability further, we investigated delayed reproductive death in chicken Rad54^−/- DT40 cells. The result indicated no difference in delayed reproductive death between wild-type and Rad54^−/- DT40 cells, suggesting that homologous recombination might play little role in the induction of delayed reproductive death. [J Radiat Res 44:441 (2003)]