Sterile mutation in Drosophila melanogaster

Abstract
SUMMARY: The number of loci which are potentially able to produce sterility genes was estimated for Drosophila melanogaster. There appear to be, on the second chromosome, about 80 loci capable of producing male sterility and about 60 loci capable of producing female sterility. These figures seem to be considerably less than (400–500) loci responsible for lethal genes.