HAMP and hereditary hemochromatosis: Genetic variants leading to excess body iron occur mainly in the haemochromatosis (HFE) gene but are also seen in hepcidin (hepcidin antimicrobial peptide (Hamp)), transferrin receptor 2 (TFR2), solute carrier family 40 member 1 (SLC40A1), haemojuvelin (HJV) and transferrin (TF) genes [9–11].