Because (1) SNPs in nAChR subunit genes CHRNA3/A5/B4 are associated with alcohol dependence phenotypes, (2) these genes are robustly expressed in the Hb-IPN circuitry, and (3) α3β4 ligands modulate ethanol consumption in rodent models, future studies should explore the role of MH-IPN nAChRs in ethanol consumption and withdrawal behaviors. This evidence concerns the gene GSTM1 and alcohol dependence.