variation). More information about the COGA study may be found in [23] Bucholz et al., 2017 and [27] Reich et al., 1998. All offspring in the age range (12–21) at the start of follow-up (2006–2007) were included. Offspring reaching the age of 12 during the course of the study (2006–2019) were also included. Subjects were interviewed at two-year intervals with the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA-IV) interview [28] Bucholz et al., 1994. The mean age at first interview was 16.1 (3.3 SD) and the mean age at last interview 23.1 (5.0). Subjects had an average of 4.0 interviews (1.7). 50.9% were female, 64.9% were EA and 30.9% AA. Ethnicity was assigned based on genotypic data, or by self-report if genotypes were not available. Subjects were members of a case family (proband with alcohol dependence −86.7% of subjects) or a comparison family (families recruited from medical or dental clinics or motor vehicle records with no selection for presence or absence of psychopathology). Non-drinkers were not excluded from the sample. The study was approved by The Indiana University Institutional Review Board (IRB) (project code: 1011004039R009, October 12, 2018). Written informed consent for the research was obtained from all participants
