Using LD score regression, a significant positive genetic correlation between alcohol consumption and smoking was identified. The overlap between alcohol consumption and smoking is well documented and other studies have shown polygenic overlap between weekly alcohol intake and the number of cigarettes smoked (rG=0.44).21 A positive genetic correlation between HDL cholesterol and alcohol consumption was also found. Increased alcohol consumption is associated with increased HDL levels52 and a Mendelian randomization study of alcohol consumption and lipid profiles found a causal effect of alcohol on increased HDL levels in the low to moderate intake range.53 rs1260326 in GCKR has previously been associated with HDL levels54 and this was one of the most significant associations with alcohol consumption in the present study. Furthermore, alcohol PRSs in GS were nominally associated with increased HDL. Our findings provide further support for the positive relationship between alcohol and HDL levels.
