In terms of genetics, different types of hereditary hemochromatosis are caused by mutations in the HFE, hepcidin (HAMP), hemojuvelin (HJV), ferroportin (SLC40)A1, and transferrin receptor 2 (TfR2) genes that correspond to genetic disorders of iron overload [63,64]. The gene discussed is SLC40A1; the disease is Tangier disease.