Effects of alleles at the agouti locus on minor skeletal variants in C57BL/6 house mice

Abstract

SummaryIn this study, five separate alleles at the agouti locus in house mice were tested for potential effects on a battery of 13 minor skeletal variants. Six genotypes (aa,ata,atat,Aa,Avya, andAya) were compared on a standard congenic background (C57BL/6). In log-linear analyses, three of the 13 characters showed significant genotype differences (another three were close to significance), and genotypes also exhibited overall significance in a multivariate randomization test. Both multidimensional scaling and clustering showed an association ofaawithata,AawithAvyaandAya, and a general separation ofatatfrom the other genotypes. Genotype differences averaged 0·63 in probit standard deviations, 0·09 when assessed by the mean measure of divergence. Since the general magnitude of effects of these major genes was quite similar to those previously estimated for presumptive polygenes from subline divergence studies, it was concluded that major genes may often act as polygenes and make important contributions to the variation in minor skeletal variants.