Common genetic variation from candidate genes hypothesised to be related to alcohol metabolism, intake or predisposition to heavy and addictive consumption will be analysed in association with teenage drinking dimensions in univariate and multivariate analyses. Individual SNPs will be analysed one at a time, then we will attempt to create 'scores' grouping the SNPs showing the most marked association.

Phenotypes to be analysed will include age at initiation, age at first binge, frequency and severity of binge drinking episodes (based on the AUDIT q.aire), total amount drunk in average week. Both cross-sectional measures and derived life-time consumption measures will be used. Where possible and appropriate, trajectories of use will be defined as part of an ongoing collaboration with the SUGAR cluster interest in alcohol use.

See Appendix for details on 18 SNPs in 13 genes selected to be genotyped and supporting evidence (highlighted SNPs). We propose that these be genotyped in all available samples from young persons in ALSPAC. However, where information on these SNPs is available as part of GWAS and imputed data on 3000 individuals, no further genotyping would be needed.