the hemochromatosis mutation is to examine the age distribution of homozygotes. Since hemochromatosis is a late-onset disease one would expect underrepresentation of the homozygous genotype in the elderly if the disease caused an appreciable number of early deaths. In fact extensive metaanalysis of 161 publications giving gene frequency data and the number of homozygotes in each population confirms these results (J Waalen et al unpublished). In the past two years numerous studies from different parts of the word have all confirmed these findings. The homozygous state is only rarely associated with illness.