Overall, in our sample ascertained for alcohol dependence, we found that craving was strongly associated with severity of dependence. This may indicate its potential role in relapse. However, based on our work and that of numerous others, there is a significant need for research to further clarify how craving should be operationalized for diagnostic and research purposes. The genomic analyses presented here lead to two important conclusions – first, much larger sample sizes will be required to detect genes of small effect for craving. Despite the relatively high prevalence for craving in our sample (relative to epidemiological cohorts), we did not succeed in identifying signals of genomewide significance. Second, despite the overlap in some of the top signals across craving and alcohol dependence, there was some evidence of specificity in association when examining genes in the dopamine pathway and further, our GWAS signals for craving do not appear to be entirely attributable to the high degree of overlap between craving and severity of alcohol dependence. There needs to be a continued effort to examine candidate genes that may be particularly
