Another recent report (Bierut et al. 2010) described a GWAS using an overlapping set of COGA subjects as well as additional subjects recruited as part of other addiction research projects. This sample included both African-American and European-American subjects, and the primary analysis sought to identify association with alcohol dependence using a case–control design. Although none of the detected associations met genome-wide criteria for statistical significance, there was some evidence to support the previously reported association in GABRA2 as well as in a gene called ERAP1, which encodes the enzyme endoplasmic reticulum aminopeptidase 1 (Bierut et al. 2010). Finally, a GWAS in a sample of twins and their families recruited in Australia is currently being analyzed.
