GS is a family- and population-based study comprising 24 096 individuals aged between 18 and 99 years.24, 25 Genome-wide genotype data are available for 19 858 individuals.26 Alcohol consumption was assessed using a preclinical questionnaire. Participants self-identified as current drinkers, former drinkers or never drinkers. Average consumption was self‐reported units of alcohol consumed in the previous week and these questions were prompted by a table containing the average units contained in a single measure of various drink types to assist participants in the calculation of weekly intake. Any GS individuals or relatives of GS individuals were removed from the UKB sample before GWAS analysis.
