Data from three human populations were used to investigate the putative relationship between genetic and morphological variances. There was no evidence to support the hypothesis that individuals heterozygous at a small number of marker loci are more often near the mean for anthropometric characters than are homozygotes. In one population (Otmoor), apparent support for the hypothesis was due to the confounding factors of correlations between anthropometric traits and population subdivision. It is unlikely that such relationships can be detected by intrapopulation comparisons because of the low association between measured and total heterozygosity.