The major contribution of this study is the demonstration of the association between rs279871 and the onset of drinking, even though several studies have failed to link rs279871 with actual AD in this age group (Dick, Agrawal, et al., 2006; Dick, Aliev, Latendresse, Porjesz, et al., 2013; Melroy et al., 2014; Sakai et al., 2010). The lack of a relationship between rs279871 and adolescent AD may be due to the limited availability of alcohol to adolescents and the time required for progression from initiation of drinking, escalation of its use, and development of alcohol dependence. Two lines of evidence support this. First, the Monitoring the Future Study (Johnston et al., 2016) reports an annual prevalence for alcohol use across 8th, 10th, and 12th graders (ages 14–18, the approximate age range of our sample) of 40%; this diminishes to a 30-day prevalence of 22%, and further decreases to a daily prevalence of <1%. Second, data from Wave 1 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) suggest that, on average, it takes 5.2 years to progress from initiation
