A Study of Deleterious Genes in Some Natural Populations of Drosophila melanogaster in Japan

Abstract
Four natural populations of D. melanogaster in western and central Japan were studied. Lethal chromosome frequencies, allelic rates of lethal genes, and homozygous viabilities of quasi-normal chromosomes were estimated in the second chromosomes of each population. The combined frequencies of lethal and semi-lethal chromosomes in each population were 7. 3, 15.1, 15. 7 and 20.1%. The mean viabilities of quasi-normal chromosomes in 3 populations were about 32%. The allelic rates within these 3 populations were 4.1, 5. 3 and 70%.