HLA-DRB1 and hepatitis A virus infection: The associations with concordant trends across infections and autoimmune disease are conceptually harder to speculate about, perhaps, but it should be noted that, with the exception of DRB1*0801 and hepatitis, the effect sizes of the associations with infections in those cases are smaller, with the average absolute value of the effect size (regression coefficient) being ~ 0.08 (compared to ~ 0.47 for autoimmune disease).