The C282Y mutation is common in Caucasians, especially in people of northern European descent. Approximately 10% of Caucasian Americans are heterozygous carriers of a single C282Y mutation.11 A greater percentage are carriers of the H63D mutation, but this mutation is much less clinically significant.
HH appears most prevalent among people of Celtic descent in the Northern British Isles--Scotland, Ireland, and Great Britain. Persons of Celtic descent in the United States, Australia, and France also have a relatively high incidence of HH. Approximately 1 out of 250 individuals in the United States are homozygous for the C282Y mutation, although the number with a clinical diagnosis of HH is lower. The prevalence of HFE mutations in African Americans and Hispanic Americans is low.