Partial correlations (controlling for sex) between the polygenic scores and alcohol problems are presented in Figure 1. As expected, higher polygenic scores predicted higher alcohol problems at age 14 (range of Pearson partial correlations 0.07–0.08, all p-values < 0.01). This is consistent with previous studies of other psychiatric conditions (such as bipolar disorder [19], schizophrenia [43] and externalizing disorders [40]) in showing that polygenic scores derived from GWAS weights from one sample can have predictive validity in an independent sample. Furthermore, our effect sizes were similar in magnitude to those observed in a polygenic analysis of a behavioral disinhibition measure (which included antisocial behavior, nicotine use/dependence, alcohol consumption and dependence, and drug use) [40].
