Transcriptome-wide expression correlation analysis showed that expression of NR2C2, ZFYVE20, CAPN7 and SH3BP5 transcripts was significantly correlated with each other both in Brain and PBMC. Their expression was also significantly correlated with many alcohol or nicotine dependence-related genes (although some of these genes have not been widely replicated so far; data not shown). These genes were from the dopaminergic (DRD1, DRD2, NCAM1, TTC12, DRD3, DRD4, SLC6A3 and TH)[Batel et al., 2008; Stapleton et al., 2007], serotoninergic (HTR1B, HTR2A, HTR3B and SLC6A4)[Hasegawa et al., 2002], cholinergic (CHRM1, CHRNA1, CHRNA3, CHRNA7, CHRNB2, CHRND and CHRNG)[Lou et al., 2006; Saccone et al., 2009], GABAergic (GABARAP, GABBR1, GABRA1, GABRA2, GABRA4, GABRA6, GABRB1, GABRB2, GABRB3, GABRG1, GABRG2 and GABRG3) [Chang et al., 2002], glutamatergic (GAD1, GRIK2, GRIK3, GRIN2A, GRIN2B, GRIN2C, GRM5 and GRM7) [Edenberg et al., 2010], histaminergic (HNMT) [Oroszi et al., 2005], endocannabinoid (CNR1) [Zuo et al., 2007], opoid (OPRD1, OPRM1 and POMC)[Zhang et al., 2008], alcohol metabolic (ADH5 and ALDH3A2)[Luo et al., 2006; Uhl et al., 2008] and neuropeptide (NPY1R, NPY2R and NPY5R)[Wetherill et al., 2008] systems (α=4.2×10-7).
