Isozyme variability in species of the genus Drosophila. VII. Genotype-environment relationships in populations of D. melanogaster from the eastern United States

Collections of D. melanogaster were analyzed for genetic variation at nine enzyme loci. Allelic frequencies were determined, and comparisons between observed phenotypic proportions and those expected under equilibrium conditions were made. A significant tendency toward homozygote excess was noted. Relationships between patterns of genetic variability and between patterns of genetic and environmental variability were examined by the method of principal components and correlation analysis. Several of the loci showed a clinal pattern in gene frequencies, and overall there was an appreciable amount of genetic-genetic and genetic-environmental association.This work was supported by PHS Research Grant No. GM 11546 and AEC Contract No. AT-(40-1)-3980. Paper No. 4026 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina.