Purpose: Examine the penetrance (defined by high transferrin saturation [TS]) of C282Y and H63D in the U.S. population.
Methods: 5171 participants from the Third National Health and Nutrition Examination Survey, 1992 to 1994.
Results: 77.1% (95% confidence interval [CI], 2.3, 95.1) of men and 51.9% (95% CI, 0, 84.2) of women with C282Y homozygosity had high TS. The associations of H63D homozygosity with high TS were stronger in people aged 50 years or older than in younger persons. Among Mexican-Americans, simple H63D heterozygosity was associated with high TS.
Conclusions: The associations between HFE genotype and high TS may vary by sex, age, and ethnic group.