Identification of the eleventh complementation group of UV-sensitive excision repair-defective rodent mutants.

The drug-sensitive mutant UVS1, isolated from the Chinese hamster cell line CHO9, was previously found to complement the UV sensitivity of the excision repair-defective rodent mutants representative of groups 1 to 8 (Hata et al., Cancer Res., 51: 195-198, 1991; M. Numata et al., personal communication). Recently two new complementation groups of UV-sensitive CHO mutants, e.g., groups 9 and 10, have been identified (Stefanini et al., Cancer Res., 51: 3965-3971, 1991). In this paper we demonstrate that the repair defect in UVS1 cells is genetically different from those present in the mutants CHO7PV and CHO4PV, representing groups 9 and 10, respectively. Therefore, UVS1 represents a new complementation group of UV-sensitive rodent cell lines, the eleventh group.