Development of a new biochemical mutation test in mice based upon measurement of enzyme activities. II. Test results with ethyl methanesulfonate (EMS).

An experiment with ethyl methanesulfonate (EMS) was conducted to determine the feasibility of detecting chemically induced mutations in mice by quantitative analysis of metabolic characters using the test procedure of Feuers et al. (1982). A test population of 518 F1 mice from matings of untreated C57BL/6J females to C57BL/6J males treated with 0, 100, 175 or 200 mg/kg EMS was evaluated according to a set of multi-level biochemical and genetic screening criteria. The goal of the assay was identification of F1 individuals heterozygous at an unspecified locus for an induced mutant allele which altered the activity of one or more of 19 enzymes in brain and liver tissues of their F2 and F3 progeny, 8 individuals among a population of 345 F1's from the EMS-dosed groups were classified as confirmed mutants having at least 2 of their F2 progeny exhibiting the same enzyme aberrancy and transmitting this aberrancy to the F3 generation. No confirmed mutants were detected in the control population of 173 F1 individuals. These results indicate that this test method can be used to detect chemically induced mutations expressed as quantitative alterations in enzyme activity.