Mutagenic effects of bleomycin in Drosophila melanogaster

Although bleomycin (BLM) induces structural chromosome damage, eg, in human lymphocytes, no, or at best a weak, mutagenicity of this substance has been observed after the application of two well-established mutagenicity screening procedures, the Ames test and the sister-chromatid exchange (SCE) test. After feeding BLM to Drosophila melanogaster males we too, observed only a weak mutagenicity as measured by the frequency of recessive sex-linked lethal mutations. These results are based on the analysis of postmeiotic germ cell stages (spermatozoa, spermatids). No autosomal translocations were found in the same experiments. BLM was also fed to Drosophila females under conditions similar or identical to those of the experiments with males. We observed a considerable sensitivity of Drosophila oocytes to the induction by BLM of recessive sex-linked lethal mutations and X-chromosomal aneuploidy (nondisjunction and chromosome loss). Our oocyte results demonstrate that the extensively used antitumor agent bleomycin has to be considered as mutagenic.