Detection of chemical mutagens using Muta Mouse: a transgenic mouse model

A transgenic mouse strain with a high copy number of rescuable lacZ sequences was evaluated for its effectiveness in detecting lacZ- mutations in selected tissues. Procarbazine, cyclophosphamide, ethylnitrosourea, 7,12-dimethylbenz[a]anthracene (DMBA), acrylamide and chlorambucil were tested following either single or repeated dosing regimens. Bone marrow, liver, skin and testis tissues were selected to assess as target sites for mutation. Bone marrow, liver and testis tissues were examined for mutation following exposures to ethylnitrosourea and chlorambucil. Increased mutant frequencies were found for both chemicals in all three tissues. Bone marrow tissue was examined for mutation following procarbazine, cyclophosphamide and acrylamide exposures, and skin was examined for mutation following dermal application of DMBA. Mutation induction was observed in all cases. The results obtained from this investigation demonstrate the applicability of this transgenic mouse as an effective model to detect and analyze gene mutation in selected organs including germinal tissues. Studies of organotrophic chemical mutagens and carcinogens are possible with this model as are studies of the susceptibility of germinal tissues to mutagen exposures.