TMPRSS6 and hemochromatosis: It is possible that the association we observed between the serum iron–raising allele of rs1800562 (C282Y) in HFE and poorer word recall is an indicator of any effect of a predisposition to hemochromatosis, a syndrome often accompanied by fatigue and malaise (23), and not directly of serum iron, because this association was not observed for the rs4820268 (TMPRSS6) genotype.