The adolescent and young adults study is a sample of subjects from the COGA study who had at least one assessment between the years 1989–2008 when the subjects were between the ages of 12 and 25 years (Table 2). Subjects were recruited from families affected with alcoholism (either as a first- or second-degree relative) and from community-based comparison families. For this analysis, 2039 adolescents and young adults who ever had a drink of alcohol were studied. All subjects were of European descent. This sample is independent of the COGA case-control sample.
