The availability of SNP data across chromosome 2 as part of the GWAS panel allowed us the opportunity to follow-up the chromosome 2 findings without having to a priori define a targeted region. We previously conducted a systematic SNP screen of LD-tagging SNPs across a 2 LOD support interval bracketing a linkage peak on chromosome 7 in the COGA sample [Dick et al., 2008]. In that systematic screen, strong evidence for association was detected with only a single gene (ACN9), a surprising result since we know that linkage is not a powerful technique for detecting genes of small effect, and we hypothesize that linkage peaks that are detected for complex traits represent the involvement of multiple genes in the region, an idea that has been supported in following up other linkage peaks in the COGA sample, for example on chromosome 4 [Edenberg et al., 2004, 2006, 2007]. In fact, several other genes have been detected in the vicinity of the chromosome 7 peak in COGA [Hinrichs et al., 2006; Wang et al., 2004, 2007], though these were located outside the
