Contet (2012) surveyed the existing literature and noted that multiple functional categories were associated with a “predisposition” to excessive ethanol consumption and in most cases each of the categories have been supported by multiple publications (see Table 2 in Contet, 2012). Some regional specificity for each of the functional categories was also noted; however, the regional differences in gene expression were generally larger than those associated with selection for preference or binge drinking (Kimpel et al., 2007; Mulligan et al., 2011). Subsequent studies have confirmed and extended the “region” effect (e.g., Melendez et al., 2012; Osterndorff-Kahanek et al., 2015; Smith et al., 2016; Mulligan et al., 2017). The data in Supplementary Table S1 again confirm marked differences in regional gene expression. Fifty or more genes in each of the three regions show a 10-fold higher expression when compared with at least one other region. In no region was selection associated with a change in expression of >2-fold and in most cases, selection was associated with small changes in expression (<30%) among the genes included in the DE analyses (see above).
