To determine if genetic variants associated with theta EEG coherence would point to genetic factors important for AUD, we conducted a multi-trait GWAS of eight measures of parietal theta EEG coherence in 8,810 individuals from the Collaborative Study on the Genetics of Alcoholism (COGA). We aimed to characterize these genetic findings with respect to alcohol use behavior (maximum drinks in a 24-hour period and DSM-5 symptom count) and related aspects of brain structure and function shown to be aberrant in AUD (using MRI and EEG data) both in a subset of COGA subjects as well as in replication samples (UK Biobank MRI subsample30 and Psychiatric Genomics Consortium-Substance Use Disorder31). In addition, we also examine differential expression of implicated genetic variants in various brain regions in individuals in the general population. Because of prior evidence indicating that the effects of genetic variants on neural oscillations may differ throughout development32, we examined developmental effects of the most significant theta EEG coherence GWAS findings on EEG coherence throughout adolescence and young adulthood in a subset of individuals followed longitudinally, including the assessment of gender differences in these associations.
