Demographic information was collected from all participants, including age, sex, ethnicity, education, and alcohol use/dependence indices (Table 1). Independent t-tests (or χ2 for dichotomous variables) were conducted on all demographic variables, and except for a trend level difference on alcoholism severity factor scores (p=0.09), no significant differences between genotype groups were observed (ps>0.10). Quantity and frequency of alcohol use was assessed using the 30-day timeline follow-back (TLFB; 16). Alcohol dependence and the exclusionary psychiatric diagnoses were assessed using the Structured Clinical Interview for DSM-IV (SCID; 17) under the supervision of a licensed clinical psychologist (LAR). DSM-IV symptoms of alcohol abuse and dependence were recorded for a total of 11 possible symptoms. All participants completed the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar; 18); Alcohol Dependence Scale (ADS; 19), Drinkers Inventory of Consequences (DrInC-2R) questionnaire (20), and the Penn Alcohol Craving Scale (PACS; 21). No individuals reported clinically significant levels of alcohol withdrawal at time of assessment as indicated by CIWA-Ar score (scores ≤6).
