those without childhood adversity the mean difference in the alcohol phenotypes between those with the GG genotype and those with the AA/AG genotype is evaluated. Last, the IC, i.e., the difference in these two mean differences is evaluated, to determine if the ADH1B effect is greater among those who experienced childhood adversity compared with those who did not. Likelihood ratio chi-square tests were used to assess the statistical significance of the IC and mean differences. Furthermore, as the IC indicates the difference in the slopes between those with the AA/AG genotypes and those with the GG genotype by childhood adversity status, plots of regression adjusted (for sex, age and ethnicity) mean phenotypes are presented to facilitate interpretation. No significant association was observed between childhood adversity and ADH1B-rs1229984, thus gene-environment correlation was not observed and was not a potential confounder of the results.
