Results from the SNP x rAOS interaction model are summarized in Table 3; the top 30 findings correspond to p-values less than or equal to 0.001. These p-values correspond to the 2-degree of freedom for the joint-significance of main effect and interaction terms. Genes and chromosomal positions are also listed for these top findings, and p-values from the main-effect model (Equation 2) for these loci are listed. A number of the genes enumerated in Table 3 correspond to findings that were identified in the initial candidate gene analysis of these data (Saccone et al. 2007); these include the nicotinic receptor gene cluster on chromosome 15 (CHRNA5-A3-B4) and its flanking regions (e.g., IREB2), DBH on chromosome 9, and KCNJ6 on chromosome 21. However, a number of new findings emerge. The most prominent new finding involves GRIN2B, for which two SNPs with rather low inter-correlation (R2=0.06) yielded p-values less than 10−4 in the interaction model. Other examples of genes containing SNPs that were highly significant in the interaction model, even though they did not reach p<0.05 in the main effect model are
