African iron overload

African iron overload is an iron overload disorder first observed among people of African descent in Southern Africa and Central Africa. It is now recognized to actually be two disorders with different causes, possibly compounding each other:

This disorder can be treated with phlebotomy therapy or iron chelation therapy.

Symptoms can vary from one person to another. It depends on the extent of accumulation and on the body location of the accumulation. African iron overload can be considered in patient with some of these conditions.

Originally, this was blamed on ungalvanised barrels used to store home-made beer, which led to increased oxidation and increased iron levels in the beer. Further investigation has shown that only some people drinking this sort of beer get an iron overload syndrome, and that a similar syndrome occurred in people of African descent who have had no contact with this kind of beer (e.g., African Americans).

This led investigators to the discovery of a gene polymorphism in the gene for ferroportin, which predisposes some people of African descent to iron overload.

Preparing beer in iron pots or drums results in high iron content. The iron content in home-brewed beer is around 46–82 mg/L, compared to 0.5 mg/L in commercial beer.

The SLC40A1 gene encodes for ferroportin. Ferroportin/SLC40A1 Q248H mutation in exon 6 occurs as a polymorphism in individuals of sub-Saharan African descent, but it was not identified in western Caucasians.

Q248H has not yet been conclusively found to be responsible for iron overload. It is found in a minority of African American and Native African with primary iron overload but was not found more regularly in Native southern Africans with dietary iron overload. It is also not associated with a statistically significant increase of risk in African Americans and Native Americans. In fact, studies have shown that SLC40A1 Q248H aggregate allele frequency is higher in Native Africans than the aggregate allele frequency in African Americans.