In the present investigation, we studied the genetic architecture of an alcohol consumption phenotype – maximum habitual (“in a typical month…”) alcohol use, or MaxAlc -- in the MVP sample (19). We used two strategies to increase power for risk variant identification: a large sample size and substantial informativity of the phenotype. We included 143,965 MVP participants, and we used MaxAlc defined as a quantitative phenotype. A different phenotype, “maximum number of drinks consumed in any 24-hour lifetime period” often called MAXDRINKS, has previously been studied (5, 20). The trait definitions differ in that MaxAlc reflects typical habitual (daily) maximum usage, as opposed to the maximum use ever, which might be on a single occasion. Heaviness of habitual alcohol use may be more correlated with risk of AD than MAXDRINKS (21). Accordingly, we expected that our analysis would be informative regarding the mental and physical consequences of excessive alcohol consumption and alcohol dependence.
