Addiction molecular genetics: 639,401 SNP whole genome association identifies many "cell adhesion" genes.

Addictions are substantially heritable complex disorders. We now report whole genome association studies that identify 89 genes likely to contain variants that contribute to addiction vulnerability, using previously- and newly-validated microarray based pooling assays. Each gene contains clustered single nucleotide polymorphisms (SNPs) that display significant allele frequency differences between abusers and controls in each of the two samples studied with 639,401 SNP arrays and confirmatory SNPs from each of two other abuser/control samples. These genes are implicated in interesting functions, including "cell adhesion" processes that help to establish and maintain neuronal connections of special relevance to addiction's memory-like features. (c) 2006 Wiley-Liss, Inc.