Since the introduction of microarray technology, transcriptome profiling of human postmortem brain tissue has been used to study the genomics of alcohol dependence (reviewed in (Farris & Mayfield, 2014; Mayfield, Harris, & Schuckit, 2008)). The functional categories of over-represented, differentially expressed genes that have been identified suggest that the transcriptional effects of long-term alcohol consumption contribute to neurotoxicity and changes in neuroplasticity. However, the biological significance of the individually expressed genes is not apparent in genome-wide transcriptome studies. Transcriptomes from complex tissues, such as human brain, may be organized into networks of co-expressed genes that are thought to better reflect the biological functions and organization of the tissue (Farris et al., 2015a; Oldham et al., 2008; Ponomarev et al., 2010).
