Adolescence is typically the period of development when alcohol use is initiated and regular patterns of use are established (Swendsen et al., 2012). This period is characterized by rapid transitions in the degree to which individual differences in alcohol use is attributed to genetic or environmental factors, with environmental factors predominating in early adolescence, while genetic factors increase in importance over time (Dick et al. 2007; Kendler et al. 2008; Viken et al. 1999). Both alcohol-specific genetic factors (Kendler et al. 2007; Kendler et al. 2003; Macgregor et al. 2009; Hicks et al. 2004) and non-specific genetic factors that impact general externalizing behavior influence alcohol consumption and the risk for developing alcohol use disorders across adolescence into adulthood (Kendler et al. 2003; Krueger et al. 2002; Hicks et al. 2004). Although there is a substantial literature on the genetic influences on externalizing disorders in adolescence (Stallings et al. 2005; Stephens et al. 2012; Dick et al. 2009) and a separate literature on the genetic influences on alcohol use disorders in adulthood (Rietschel and Treutlein, 2013), little is known about the etiologic role of these two types of genetic risk on alcohol-related behaviors across development.
