Stores iron in a soluble, non-toxic, readily available form. Important for iron homeostasis. Has ferroxidase activity. Iron is taken up in the ferrous form and deposited as ferric hydroxides after oxidation. Also plays a role in delivery of iron to cells. Mediates iron uptake in capsule cells of the developing kidney (By similarity). 4 Fe(2+) + 4 H(+) + O2 = 4 Fe(3+) + 2 H2O Oligomer of 24 subunits. There are two types of subunits: L (light) chain and H (heavy) chain. The major chain can be light or heavy, depending on the species and tissue type. In the human liver, the heavy chain is predominant. The functional molecule forms a roughly spherical shell with a diameter of 12 nm and contains a central cavity into which the insoluble mineral iron core is deposited. Expressed in the liver. The disease is caused by variants affecting the gene represented in this entry. In a Japanese family affected by HFE5, a single point mutation has been detected in the iron-responsive element (IRE) in the 5'-UTR of FTH1 mRNA. This mutation leads to an increased binding affinity for iron regulatory protein and thereby to the efficient suppression of mRNA translation. Belongs to the ferritin family. Extended N-terminus. Ferritin entry