In a male cohort of the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders (Kendler et al. 2006), Kendler and colleagues examined the influence of the two components of genetic risk across development (Kendler et al. 2011). Using retrospective reports of alcohol use across the lifespan, these authors found that the importance of non-specific genetic factors related to externalizing behavior in maximal alcohol consumption is greatest during early to mid-adolescence, peaking at ages 15–17 years and then declining slowly towards adulthood. In contrast, the influence of alcohol-specific genetic factors increased slowly through mid-adulthood. However, several important questions regarding the depth and limitations of these effects remain.
