Initial Phase of the GSCAN GWAS project

Alcohol and tobacco use are complex behavioral phenotypes that show highly polygenic inheritance. Although genome-wide analyses have found a small number of common variants associated with these phenotypes, there likely remain... [ view full abstract ]

Alcohol and tobacco use are complex behavioral phenotypes that show highly polygenic inheritance. Although genome-wide analyses have found a small number of common variants associated with these phenotypes, there likely remain many additional associated loci to be found, which will provide clues to biological mechanisms involved in addiction. GWAS & Sequencing Consortium of Alcohol and Nicotine use (GSCAN) is an international consortium to conduct genetic association analyses across many studies and hundreds of thousands of individuals. Our current freeze of 29 studies have provided summary statistics from association studies with six smoking/alcohol related phenotypes: cigarettes per day (N = 256,658), regular versus never smoker (N=991,257), smoking cessation (N=420,466), age of initiation of regular smoking (N=260,513), drinks per week (N=632,043) and drinker vs non-drinker (N=688,077). Preliminary results indicate discovery of dozens of novel independent loci across the six traits, as would be expected for samples of this size. More refined and finalized results will be presented. We will also present secondary analyses using these results to generate polygenic risk scores and genetic correlations between the six addiction phenotypes.