The Study of Addiction: Genetics and Environment (SAGE)21,22 is an alcohol dependence GWAS that selected cases and controls from large investigations targeting non-opioid substance dependence. Each contributing institution’s IRB approved the recruitment protocols. All participants provided written informed consent. Since SAGE did not ascertain participants on the basis of opioid dependence, it included fewer severely dependent individuals and more participants of unclear affection status. We operationalized the ODE group as DSM-IV opioid dependence and the OUIP group as opioid misusers who met at most one dependence and no abuse criterion. Limiting inclusion to EA participants, we retained 190 ODE and 319 OUIP individuals.
