Polygenic scores predicted the externalizing disorder composite in adolescents and young adults and accounted for 6% of the variance after controlling for gender and age (Table 1). Polygenic scores continued to predict the externalizing disorder composite after controlling for parental externalizing disorder history (Table 1). Table 2 summarizes the variance (R2) in subclinical externalizing behavior and impulsivity-related traits explained by polygenic scores after controlling for gender and age. Higher polygenic scores predicted higher Achenbach externalizing and impulsiveness in adolescents and young adults. Higher polygenic scores predicted lower conscientiousness in adolescents, but not young adults. Higher polygenic scores predicted higher sensation seeking in young adults but not adolescents.
