Based on these genome‐wide association results, several analyses were performed to investigate interesting targets, brain expression of genes, and links to psychiatric and neurological phenotypes. Alcohol dependence has been found to be linked to SNPs in gamma‐aminobutyric acid‐receptor subunit alpha 2 gene (GABRA2) (Dick et al., 2006; Edenberg et al., 2004; Porjesz et al., 2002; Rangaswamy & Porjesz, 2008; Rangaswamy et al., 2002). GABRA2 and alcoholism have been linked to individual differences in beta oscillation power (12–28 Hz) (Edenberg et al., 2004; Porjesz et al., 2002; Rangaswamy & Porjesz, 2008; Rangaswamy et al., 2002). We aimed to replicate this last result using our genome‐wide study of beta oscillation power. The association was found to be present in the gene‐based test (Smit et al., 2018). Gene‐expression analysis of the GABRA2 gene suggested that beta power was most strongly associated with hippocampal expression. This suggests that hippocampal GABRA2 expression affects beta oscillations and may be linked to the pivotal role hippocampal GABA plays in habit‐forming and reward processing in alcohol dependence (Enoch, 2008). Interestingly, this is in line with ongoing work by
