When stratified by rs279871 genotype, there were no significant differences between subjects with AA and AG genotypes in age, gender, education, family history status, family history density, AUDIT scores, smoking, or drinking patterns (Table 1). None of the subjects had evidence of Axis-I psychiatric or neurological disorders of the brain or failed olfactory screening. Although all subjects denied using illicit drugs, one AG subject tested positive for cannabinoids on the placebo day. One AG subject tested positive for amphetamines on both placebo and alcohol days, and one AA subject tested positive for amphetamines only on the alcohol day. This latter subject was excluded from analyses of the alcohol session data because of obvious acute intoxication and difficulty detecting odors on that day. No subject otherwise exhibited obvious cognitive or behavioral abnormalities in either session. An additional AA subject's fMRI data could not be used for the alcohol session because of excessive head motion during imaging. This resulted in 13 AA and 23 AG subjects available for image analysis in placebo scans, and 11 AA and 23 AG functional imaging datasets when scanning under alcohol infusion.
