TFR2 and Tangier disease: The most studied pathophysiologies were iron overload and iron deficiency.53 Iron overload occurs in two diseases, hereditary hemochromatosis and hemoglobinopathy-related anemia, which is also called iron-loading anemia.52 When mutation occurs in gene coding hepcidin itself or in genes that are major inducers of hepcidin activating pathways (TfR-2 and HFE2), low levels of hepcidin and systemic iron overload (hemochromatosis) are observed.53