The purpose of this study was to perform a transcriptome analysis of mRNA and miRNA expression to identify gene co-expression modules correlated with excessive alcohol consumption in human NAc. The NAc is a central component of the mesocorticolimbic system (MCL) and has been shown to be involved in addictive behaviors. A current theory on the mechanism by which the NAc modulates addiction is that the NAc integrates signals from other MCL regions on the single-neuron level in order to modulate goal- and motivation-directed behavior [60–62]. We assembled our expression data with previously generated genome-wide genotype data to identify NAc-specific cis-eQTLs affecting the expression of mRNA and miRNA network hub genes. We then tested whether the eQTLs were enriched for AD GWAS signals. This is the first study to show that genetic variants (previously shown to be associated with AD or ARP) are eQTLs, which affect the differential expression of genes between AD cases and controls in NAc.
