Association of ferroportin Q248H polymorphism with elevated levels of serum ferritin in African Americans in the Hemochromatosis and Iron Overload Screening (HEIRS) Study.

The ferroportin (FPN1) Q248H polymorphism has been associated with increased serum ferritin (SF) levels in sub-Saharan Africans and in African Americans (AA). AA participants of the HEIRS Study who did not have HFE C282Y or H63D who had elevated initial screening SF (> or =300 microg/L in men and >= or =200 microg/L in women) (defined as cases) were frequency-matched to AA participants with normal SF (defined as controls) to investigate the association of the Q248H with elevated SF. 10.4% of cases and 6.7% of controls were Q248H heterozygotes (P=0.257). Q248H homozygosity was observed in 0.5% of the cases and none of the controls. The frequency of Q248H was higher among men with elevated SF than among control men (P=0.047); corresponding differences were not observed among women. This appeared to be unrelated to self-reports of a previous diagnosis of liver disease. Men with elevated SF were three times more likely than women with elevated SF to have Q248H (P=0.012). There were no significant differences in Q248H frequencies in men and women control participants. We conclude that the frequency of the FPN1 Q248H polymorphism is greater in AA men with elevated SF than in those with normal SF.