HFE and hemochromatosis type 2: By contrast, the most common cause of genetic hyperferritinemia with iron overload is hereditary hemochromatosis, which is caused by the mutation of the HFE gene [15]; the difference with both hyperferritinemia-cataract syndrome and juvenile hemochromatosis is that high ferritin levels in hereditary hemochromatosis cannot be seen in pediatric age, because iron overload develops through adulthood.