Hemochromatosis: Niche Construction and the Genetic Domino Effect in the European Neolithic

Hereditary hemochromatosis (HH) is caused by a potentially lethal recessive gene (HFE, C282Y allele) that increases iron absorption and reaches polymorphic levels in Northern European populations. Because persons carrying the allele absorb iron more readily than non-carriers, it has often been suggested HFE is an adaptation to anemia. We hypothesize positive selection for HFE began during or after the European Neolithic with the adoption of an iron-deficient high grain and dairying diet and consequent anemia, a finding confirmed in Neolithic and later European skeletons. HFE frequency compared with rate of lactase persistence in Eurasia yields a positive linear correlation coefficient of 0.86. We suggest this is just one of many mutations that became common after the adoption of agriculture.