OBJECTIVE: To assess geographic differences in the frequencies of HFE C282Y and 
H63D genotypes in six racial/ethnic groups recruited in the Hemochromatosis and 
Iron Overload Screening (HEIRS) Study.
DESIGN: HFE C282Y and H63D genotypes of 97,551 participants, ages > or = 25 
years, who reported that they belonged to one of six racial/ethnic groups, were 
analyzed. HFE genotype frequencies were compared among the racial/ethnic groups 
and among the HEIRS Study field centers within each racial/ethnic group.
RESULTS: The distribution of HFE C282Y and H63D genotypes differed among 
racial/ethnic groups (P<.0001) and among field centers in Hispanics, Asians, 
Whites, and Blacks (each P<.05). Genotype frequencies were similar among field 
centers in Native Americans and Pacific Islanders. Frequencies of C282Y and H63D 
genotypes were greatest in Whites. The lowest frequencies of C282Y genotypes 
were observed in Asians; Blacks had the lowest H63D genotype frequencies and the 
highest frequency of the wild-type genotype. Among racial/ethnic groups, 
Hispanics had the greatest variation in HFE genotypes across geographic regions.
CONCLUSION: HFE C282Y and H63D genotype frequencies vary significantly between 
racial/ethnic groups and within some racial/ethnic groups across geographic 
regions.