DIFFERENTIAL EXCISION OF CARCINOGENIC HYDROCARBON-DNA ADDUCTS IN MOUSE EMBRYO CELL-CULTURES

Primary mouse embryo cell cultures efficiently excise DNA damage introduced by the carcinogens 7-bromomethylbenz[a]anthracene and 3-methylcholanthrene but are inefficient in excision of damage introduced by 7,12-dimethylbenz[a]anthracene. Since exposure of the cells to the latter compound does not impair their capacity for excision of adducts introduced by the bromocompound, the 7,12-dimethylbenz[a]anthracene-DNA adducts are apparently intrinsically difficult to excise.