This study tested for an enrichment of associations between SNPs in an independently assembled set of genes previously associated with alcohol outcomes (Aliev et al., 2015) and factor scores from a multivariate, hierarchical model of externalizing behaviors. Overall, the results indicated that, within an ancestrally homogenous sample (non-Hispanic White individuals), there was significant enrichment of associations between genetic polymorphisms previously identified as relevant for alcohol outcomes and a common factor underlying a broad spectrum of externalizing behaviors and impulsive/sensation seeking personality traits across time. Our “deep phenotyping” approach (Robinson, 2012) provides an important complement to many genetic association studies, which, because of their sample size burdens, more typically use cross-sectional or retrospective measures of single clinical categories. More generally, this approach illustrates how psychological science can uniquely contribute to understanding the genetic underpinnings of complex behavior through multivariate analyses of behavioral and psychiatric phenotypes.
