Variants in ABCB1, TGFB1, and XRCC1 genes and susceptibility to viral hepatitis A infection in Mexican Americans.

Hepatitis A vaccination has dramatically reduced the incidence of hepatitis A virus (HAV) infection, but new infections continue to occur. To identify human genetic variants conferring a risk for HAV infection among the three major racial/ethnic populations in the United States, we assessed associations between 67 genetic variants (single nucleotide polymorphisms [SNPs]) among 31 candidate genes and serologic evidence of prior HAV infection using a population-based, cross-sectional study of 6,779 participants, including 2,619 non-Hispanic whites, 2,095 non-Hispanic blacks, and 2,065 Mexican Americans enrolled in phase 2 (1991-1994) of the Third National Health and Nutrition Examination Survey. Among the three racial/ethnic groups, the number (weighted frequency) of seropositivity for antibody to HAV was 958 (24.9%), 802 (39.2%), and 1540 (71.5%), respectively. No significant associations with any of the 67 SNPs were observed among non-Hispanic whites or non-Hispanic blacks. In contrast, among Mexican Americans, variants in two genes were found to be associated with an increased risk of HAV infection: TGFB1 rs1800469 (adjusted odds ratio [OR], 1.38; 95% confidence interval [CI], 1.14-1.68; P value adjusted for false discovery rate [FDR-P] = 0.017) and XRCC1 rs1799782 (OR, 1.57; 95% CI, 1.27-1.94; FDR-P = 0.0007). A decreased risk was found with ABCB1 rs1045642 (OR, 0.79; 95% CI, 0.71-0.89; FDR-P = 0.0007).

Conclusions: Genetic variants in ABCB1, TGFB1, and XRCC1 appear to be associated with susceptibility to HAV infection among Mexican Americans. Replication studies involving larger population samples are warranted.