Much of the prior work involving alcohol and 5-HTTLPR points to S carriers being at increased risk for negative alcohol outcomes, including more binge drinking occasions (Chen et al., 2014; Herman, Philbeck, Vasilopoulos, & Depetrillo, 2003), more drinks per drinking occasion (Covault et al., 2007), earlier age of drinking initiation (Kaufman et al., 2007), and more frequent occasions of drinking with intentions to become intoxicated (Covault et al., 2007). Two meta-analyses support this pattern of findings (Feinn, Nellissery, & Kranzler, 2005; McHugh, Hofmann, Asnaani, Sawyer, & Otto, 2010); however, at least four studies have found the LL genotype to be the variant that confers alcohol-related risk (Hinckers et al., 2006; Hu et al., 2005; Schuckit et al., 1999; Sen et al., 2004b), and three studies found no association between 5-HTTLPR and alcohol risk (Hill et al., 2002; Kranzler, Lappalainen, Nellissery, & Gelernter, 2002; Stoltenberg et al., 2002). These contradictory findings suggest a more complex relationship than previously thought as well as the presence of intervening and/or moderating variables. Furthermore, the alcohol-related outcomes varied across the aforementioned studies, which may serve
