<unk>  can be caused by inheriting two mutated copies (alleles), one from each parent, of the genes for the proteins hemojuvelin (HFE2/HJV) or hepcidin (HAMP), and the disease can be subdivided into hemochromatosis types 2A and 2B according to which gene/protein is affected. * Type 2A is caused by inheriting two mutated alleles, one from each parent, for the HJV (aka HFE2) gene, which encodes the protein hemojuvelin. Hemojuvelin is responsible for the maintaining correct levels of the protein hepcidin, which regulates iron absorption in the blood. Without functional hemojuvelin, hepcidin levels are reduced, and the amount of iron absorbed into the blood during digestion is unable to be halted. * Type 2B is caused by inheriting two mutated alleles, one from each parent, for the HAMP gene, which encodes the protein hepcidin. Hepcidin is responsible for regulating absorption of iron from the small intestine to the blood during the digestion of food, such to prevent blood iron levels from becoming too high. A lack of functional hepcidin prevents the body from stopping iron absorption when it has already reached adequate levels. Type 2A is the most common form, accounting for roughly 9 out of every 10 cases of the disease.
Juvenile hemochromatosis
Hereditary haemochromatosis
Hemochromatosis type 4
Haemochromatosis type 3
Wilson's disease
Neonatal hemochromatosis
Gaucher's disease
Wilson–Mikity syndrome