Ethyl methanesulfonate-induced mutants in the Y chromosome of Drosophila melanogaster

Male sterility mutants have been induced in the Y chromosome by treatment with ethyl methanesulfonate. Complementation tests with deficient Y chromosome tester stocks revealed that many of the mutant Y chromosomes were deficient for more than one male fertility locus. Cytological analysis showed that in two cases of multiple deficiency the long arm of the Y chromosome was grossly reduced in size. Several of the mutant Y chromosomes were sensitive to the temperature at which males were reared, males being partially fertile when reared at 18° and sterile when reared at 25°.