Hemochromatosis results from genetic defects of iron-metabolism-related genes, including HFE, HAMP (encoding hepcidin), HJV (hemojuvelin), TFR2 (transferrin receptor 2), and SLC40A1 (ferroportin) genes (5), whose functions are described below. The gene discussed is SLC40A1; the disease is hemochromatosis type 1.