SAGE consisted of 2593 unrelated European-American subjects. Of these, 2336 individuals who reported regular drinking were included in these analyses. Subjects were selected from three large, complementary studies: COGA,19 Family Study of Cocaine Dependence (FSCD)20 and Collaborative Genetic Study of Nicotine Dependence (COGEND).21 Further details of the SAGE sample are available elsewhere.17 One hundred and twenty nine individuals who were both in SAGE and the COGA discovery sample were excluded. The sample consisted of alcohol-dependent cases (N=1167, mean age at onset 24.7 years) and alcohol-exposed controls (N=1169).
