Mutagenic effects of nitrogen mustard derivatives of azo-benzene compounds in drosophila melanogaster

Abstract

The azo-mustard 4-di-2″-chloroethylaminoazobenzene-2′-carboxylic acid was found to be mutagenic in Drosophila melanogaster males. The mutagenic effect was found only in pre-meiotic germ cell stages and, of these, late spermatids were the most sensitive. Sterility or egg unhatchability was found to be due to aspermia. Within the germ cell stage sterility was found to be correlated to the mutagenic effect suggesting that the differential response of germ cell stages to the mutagenic action of the mustard was not a genetic phenomenon. The induction of sex-linked recessive lethal mutation was found to be linearly related to dose. The rate of excretion of the azo-mustard was determined by a spectrophotometric method. At least 90 per cent of the injected material appeared to be excreted in an unreduced form, in contrast to the expected mode of action of the compound which required prior reduction of the azo-bond. A further member of the azo-mustard series, its non-mustard homologue and a possible reduction product, were also tested for mutagenic action. Only the former was shown to be mutagenic. These results are discussed in relation to the hypothesis that reduction of the azolinkage is a necessary prerequisite for the mutagenic activity of the azo-mustards.