We used LD Score regression (LDSC) to identify genetic correlations between traits (24). This method was used to calculate genetic correlations (rg) between AUDIT total score, AUDIT-C, and AUDIT-P and 39 other traits and diseases (see Supplementary Tables 3, 4 and 5). We did not constrain the intercepts in our analysis, as we could not quantify the exact amount of sample overlap between cohorts. We used False Discovery Rate (FDR) to correct for multiple testing (25). We also used LDSC to examine genetic correlations between various dichotomized versions of AUDIT and DSM-IV defined alcohol dependence (13). To test for significant differences between the genetic correlations, z-score statistics were calculated (see Supplementary Table 6).
