We used a summary data-based conditional analysis approach to identify the independent lead SNP associated with AUD and DPW. This conditional and Joint analysis (COJO)60 approach is implemented in Genome-wide Complex Trait Analysis (GCTA) software61 package and is valuable when the individual-level genotype data is not available for the conditional analysis. To perform the COJO analysis we used the summary statistics of AUD and DPW GWAS along with the European subset of COGA samples as the LD reference panel.
