We identified a total of 25 credible causal genes based on robust evidence using multiple positional and functionally-informed gene-based approaches. Notably, DLGAP1, which has been previously implicated in OCD pathogenesis10,51, was not identified in either the GWAS or in the gene-based analyses. Of the 25 genes that were implicated, 15 were within 6.5 kb of a SNP that surpassed genome-wide significance in the meta-analysis. In addition to the four genes discussed above, several others are of particular interest, including WDR6 and DALRD3, which had the strongest evidence from the gene-based analyses. These genes lie in a gene-rich region on chr3p21.31, which in addition to harboring multiple genome-wide significant SNPs, has been previously associated with a broad range of psychiatric disorders and related traits, including schizophrenia39, well-being52, and the worry-subcluster of neuroticism53.
