COGA is a multi-site study that began in 1989 with the goal of identifying vulnerability and protective genes for AUD (Dick et al., 2023). High-risk and comparison families were ascertained and enrolled in the study via probands who were in treatment at 6 sites for what was then termed “alcohol dependence” (Johnson et al., 2023, Nurnberger et al., 2004, Dick et al., 2023). All data collection sites used consistent data collection procedures. This study was approved by the Institutional Review Boards from all centers and every participant provided informed consent. All participants were interviewed using the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) (Bucholz et al., 1994, Hesselbrock et al., 1999), which includes a thorough history of AUD symptoms including ages of symptom onset and recency. In the present analyses, AUD cases consisted of participants who reported two or more DSM-5 AUD criteria occurring within the same 12-month period (American Psychiatric Association, 2022). Among individuals who met lifetime AUD criteria, those who reported no current criteria other than craving for at least 12 consecutive months were coded as 12-month
