Table 3 shows that in AAs, stimulant dependence was significantly but modestly genetically correlated with alcohol dependence (r2 = 0.11, p = 8.0 × 10−16), ADHD (r2 = 0.05, p = 3.5 × 10−5), and anxiety disorder (r2 = 0.03, p = 9.2 × 10−3). In EAs, the correlation with both alcohol dependence and ADHD was nearly double the magnitude and substantially more significant (r2 = 0.20, p = 7.2 × 10−55 and r2 = 0.10, p = 1.5 × 10−14, respectively) than in AAs; these differences could have been due to the ancestry of the reference GWAS sample. The pleiotropy analysis showed that the variants associated with stimulant dependence also affected the risk of alcohol dependence (adjusted p = 3.6 × 10−3) and anxiety (adjusted p = 2.1 × 10−4) in EAs but not AAs. Although pleiotropy was observed for stimulant dependence and ADHD in both AAs (adjusted p = 3.0 × 10−33) and EAs (adjusted p = 6.7 × 10−35), no individual variants showed significant pleiotropic effects on stimulant dependence and any of the other disorders after multiple
