From the three significant miRNA modules, 26 miRNA hub genes in the top quartile of MM were identified (Fig 3B); however, one miRNA, hsa-miR-3676, was removed from analysis as it was reported as a tRNA fragment and not processed as a miRNA according to miRBase (www.mirbase.org). Many of the miRNA hub genes also belonged to the same miRNA gene family (<10 kb genomic distance apart). For example, hsa-miR-377-5p, -134-5p, and -382-5p from M blue are located in the same genomic cluster of chromosome 14q; this region was previously reported to contain overexpressed miRNAs in the PFC of AD cases [21]. In addition, miR-382 overexpression in the NAc was shown to attenuate voluntary alcohol intake in a two-bottle choice rat model [26]. Hsa-miR-132-3p and hsa-miR-212-3p, also in M blue, have been previously associated with schizophrenia/bipolar disorder and cocaine dependence [43–46]. Both hsa-miR-132-3p and hsa-miR-212-3p are in the same miRNA family and are important for neuronal function and long-term potentiation, as well as for neuronal survival in Alzheimer’s disease. M brown included miRNA from the hsa-miR-34b and hsa-miR-34c family, which have been
