across these genes, and the other gene located very nearby, NCAM1, has suggested that the association with substance use phenotypes extends to multiple genes in this region This underscores the necessity of understanding genomic structure in order to evaluate the role of hypothesized genes of interest. In the field of genetics, we would never test a single marker in a gene in order to make conclusions about the relevance of that gene for a given genotype. It would be the equivalent of asking a single question about whether a participant got along with his/her mother as a child, and then using the results from that variable to make conclusions about whether the home environment played a role in the outcome of interest. A developmental scientist would rightly argue that such an analysis was at best naïve, and at worst, close to meaningless, and geneticists have ignored much of the literature on genetic associations deriving from the labs of social scientists for similar reasons.
