[Iron in the era of molecular biology]

Abstract

Identification of the HFE gene and its C282Y and H63D mutations has improved the classification of iron overload disorders. Inherited hemochromatosis is due mainly, or perhaps only, to C282Y homozygosity, whereas nonhemochromatosis forms of iron overload are due to other HFE mutations and are usually responsible for mild overload precipitated by another factor such as cirrhosis or insulin-resistance. In practice, the diagnosis of inherited hemochromatosis rests on demonstration of homozygosity for the C282Y mutation; in this setting, the role of liver biopsy is to evaluate the prognosis by looking for fibrosis. In patients who are not homozygous for the C282Y mutation but have severe iron overload, causes other than hemochromatosis should be looked for before the extremely remote possibility of nonC282Y-related hemochromatosis is considered; here, liver biopsy remains of considerable diagnostic usefulness.