The additional question of under what circumstances these associations hold remains. Addressing this issue may explain some of the discrepancies in the literature on 5-HTTLPR and alcohol outcomes to the extent that previously unmeasured variables exert a moderating effect on the association between genotype and alcohol outcome. That is, the strength and/or direction of the association between 5-HTTLPR and alcohol use outcomes via SRE may depend on other variables. A likely moderator of the proposed mediation effect is parental monitoring. Broadly defined, parental monitoring comprises behaviors that parents and guardians use to attend to and track the whereabouts, activities, and social affiliations of their children (Dishion & McMahon, 1998). It has been shown to exert a substantial influence over alcohol-related risk, including consumption and sustained use (Becker et al., 2012; Kristjansson, James, Allegrante, Sigfusdottir, & Helgason, 2010; Steinberg, Fletcher, & Darling, 1994) and number of intoxication incidents (Kristjansson et al., 2010). One study found that adolescents who reported high levels of parental monitoring were more likely to be in a moderate and decreasing alcohol use trajectory group than in either
