Comparative induction of somatic eye-color mutations and sex-linked recessive lethals in Drosophila melanogaster by tryptophan pyrolysates

Abstract

The mutagenecities of the products of pyrolysis of tryptophan, Trp-P-1 and Trp-P-2, on Drosophila melanogaster were examined by measuring the effects of these compounds in inducing recessive lethals and somatic eye-color mutations. Since negative results have already been obtained by the standard procedure in males, Trp--P-1 and Trp-P-2 (0.75 to 6 mg/ml) in sucrose solution were given to females for assay of recessive lethal mutations in X-chromosomes. These compounds caused a marginal increase above the control level in the mutation frequency. For the assay of effects on somatic eye-color mutations, Trp-P-1 (200 and 400 ppm) and Trp-P-2 (400 and 800 ppm) were fed to male larvae of a tester strain carrying a genetically unstable marker set of z and w + on the X-chromosome. These compounds caused dose-dependent increases above the control level in somatic eye-color mutattions in adults. It is concluded that, under the conditions used, the somatic eye-color mutation system was more sensitive than the recessive lethal system to the mutagenic effects of tryptophan pyrolysates.