Causes of Hemochromatosis
Iron overload (hemochromatosis) can be caused by disorders such as thalassemia (an inherited blood disorder), anemia, chronic alcoholism, and other conditions. In many cases, however, iron overload is the result of a hereditary disorder, which means it is passed down from parents to children through their genes. This form of iron overload is called hereditary hemochromatosis. Hereditary hemochromatosis is also known as primary hemochromatosis. Most cases of hereditary hemochromatosis in the United States are caused by a defect in a gene called the HFE gene.

Some people get a copy of the HFE gene defect from just one parent. They are called "carriers" because they carry the defective gene and can pass it on to their children. Carriers usually do not get sick. People who get the HFE gene defect from both parents have a greater chance of developing iron overload.

There are other types of hereditary hemochromatosis that are not caused by the HFE gene defect - including , juvenile, and neonatal hemochromatosis - but they are less common.