SLC40A1 may be involved in iron export from duodenal epithelial cells and also in transfer of iron between maternal and fetal circulation. It mediates iron efflux in the presence of a ferroxidase (hephaestin and/or ceruloplasmin). Defects in SLC40A1 are the cause of hemochromatosis type 4, an autosomal dominant iron-loading disorder characterized by early iron accumulation in reticuloendothelial cells and a marked increase in serum ferritin.Synonyms: Ferroportin-1, Fpn1, Ireg1, Iron-regulated transporter 1, Metal transporter protein 1, Slc11a3, Slc39a1, Slc40a1, Solute carrier family 40 member 1