In terms of disorder specific liabilities, each disorder exhibited specific genetic effects (drug dependence a2 = 0.27, 95% CI = 0.17-0.32; conduct disorder a2 = 0.24, 95% CI = 0.15-0.33; nicotine dependence a2 = 0.21, 95% CI = 0.13-0.28; alcohol dependence a2 = 0.16, 95% CI = 0.09-0.20), though the effect for adult antisocial behavior was only marginally significant (a2 = 0.07, 95% CI = 0.003-0.14). Only conduct disorder exhibited a specific shared environmental effect (c2 = 0.19, 95% CI = 0.11-0.26). Each disorder also exhibited specific nonshared environmental influences: adult antisocial behavior e2 = 0.30, 95% CI = 0.27-0.34; conduct disorder e2 = 0.39, 95% CI = 0.35-0.43; alcohol dependence e2 = 0.38, 95% CI = 0.35-0.42; drug dependence e2 = 0.40, 95% CI = 0.36-0.44; nicotine dependence e2 = 0.32, 95% CI = 0.29-0.36.
