In the present paper, we report the results of the first genome-wide association study (GWAS) of an ERO endophenotype – frontal theta oscillations at the midline frontal electrode (Fz) during processing of target visual signals in a visual oddball paradigm. The analysis used a sample of unrelated individuals drawn from a study of alcohol-dependence. High ranking SNPs from the GWAS were selected for replication analysis in a family-based sample ascertained for alcohol dependence, implicating new regions not detected by previous linkage analyses, with a number of significant markers in or near genes that play important roles in cellular development and signal transduction pathways. Promising SNPs were also tested for association with diagnoses of alcohol dependence in both samples.
