Genotypic differences in the level of N-acetyltransferase activity in mice of inbred lines and their hybrids]

There are "slow" and "rapid" acetylator phenotypes in mice according to N-acetyltransferase activity (E.C. 2.3.1.5) (N-AT). The results of direct, back- and reciprocal crosses of mice lines with rapid acetylation phenotype (C57BL/He) show monogenic autosomic control of acetylation locus (Ac) with rapid allele dominance and sex dependence upon N-AT activity in males. So, genetic polymorphism according to the Ac locus exists in mice as well as in some other animal species and in humans. The results obtained in this study demonstrated the correlation between the N-AT level in mice and their predisposition to malignant tumors as well as dependence of cyclophosphamide action on the N-AT activity upon the genotype of an individual, which suggests a certain role of the Ac locus in tumor development.