SNPs (149 features; Supplementary Table 3) were selected based upon associations with EEG and alcohol-related traits from several recent Genome-wide Association Study (GWAS) involving EA and AA populations. These include fast beta EEG16, alcohol consumption12, 13, DSM-IV alcohol dependence14, 15, and maximum number of alcoholic drinks within 24 h31. Genotyping, imputation and quality control have been previously reported 32, 33 and can be found in Supplementary Materials.