Polymorphism at the G6PD and 6PGD loci inDrosophila melanogaster: I. Evidence for selection in experimental populations

Abstract

SUMMARYGene frequency changes were followed in 17 experimental cage populations ofDrosophila melanogasterpolymorphic for the two loci G6PD and 6PGD. From these cages it was observed that selection was favouring theFalleles of both loci when the cages were started with low frequencies of these alleles (0·20Fand 0·50F). A viability experiment and an extinction experiment also provided evidence that theFalleles of both loci were favoured. It is argued that the observed selection is not due to selective differences in genetic background of the different alleles, but is acting on the isozyme loci themselves.