Before the era of large-scale genomic research, twin and family-based studies identified a high degree of genetic overlap between the genetic risk for AUD and psychopathology by modeling correlations among family members (e.g. (60)). With the recent development of linkage disequilibrium score regression (LDSC), it is now possible to estimate the genetic correlations between specific alcohol use behaviors (Figure 1, Figure 4) and a plethora of psychiatric, health and educational outcomes using GWAS summary statistics. Most notably, the genetic overlap between alcohol consumption and AD was positive but relatively modest (rg = 0.38–0.52, 12, 18), suggesting that, although the use of alcohol is necessary to develop AD, some of the genetic liability is specific to either levels of consumption or AD.
