BIP PRS were associated with increasing problematic alcohol involvement, severe cocaine dependence, and specific levels of cannabis and opioid involvement (Supplementary Table S4). None of these associations survived correction for multiple comparisons. Alcohol: There was evidence for a dose-dependent relationship between BIP PRS and increasing number of alcohol dependence symptoms among regular drinkers with at least one symptom of dependence. Cannabis: Compared with those who had never used cannabis, BIP PRS were higher and of a similar magnitude in individuals with non-problem cannabis use and moderate dependence. Cocaine: Relative to non-users and non-problem users, those with severe cocaine dependence exhibited higher BIP PRS. Opioids: Elevated BIP PRS were associated only with mild problems (i.e., 1–2 dependence symptoms).
