HFE mutations and Alzheimer's disease.

An imbalance in brain iron status has been established in Alzheimer's Disease (AD). This iron imbalance can impact plaque formation, amyloid processing, and expression of and response to inflammatory agents. In a more general sense, a deregulation of iron homeostasis underlies the generation of reactive oxygen species leading to oxidative damage. Thus, loss of iron homeostasis can be central to the pathogenic events in AD. Recently a number of studies have begun to investigate the frequency of mutations in the HFE gene in AD. Mutations in the HFE gene occur more frequently in Caucasians than any other mutation. The two most common mutations of HFE are the C282Y (2% of the total population) and the H63D (9%. Mutations in this gene are associated with loss of iron homeostasis, alterations in inflammatory responses and in its most severe form, a clinical disorder known as Hemochromatosis. The C282Y mutation is more frequently associated with Hemochromatosis and the frequency of the H63D mutation is receiving increasing attention in neurodegenerative disorders. This review summarizes the data on HFE mutations in neurodegenerative disorders and what is known about HFE in the brain and the cell biology underlying the HFE mutation.