CBCL externalizing for those with no copies of the minor allele (β = 0.06, 95% CI [0.001, 0.12]), but not for those with one or two copies of the minor allele (MA) (β1MA = 0.01, 95% CI [−0.05, 0.06]); β2MA = −0.04, 95% CI [−0.13, 0.04]). Similarly, in the model that included parental alcohol problems (Panel B, left), life events predicted subsequent CBCL externalizing for those with no copies of the MA (β = 0.06, 95% CI [0.001, 0.12]), but not for those with one or two copies of the MA (β1MA = 0.02, 95% CI [−0.04, 0.07]); β2MA = −0.05, 95% CI [−0.13, 0.04]). In supplementary analyses that included all covariate × environment and covariate × genotype interaction terms, the interaction between life events and GABRA2 was attenuated, which is to be expected given the additional parameters in the model and corresponding loss of degrees of freedom, but did not entirely disappear (p values = 0.06 and 0.07). These results are summarized as Model 3 in Tables 3 and 4.
