In this study we present a complementary approach to collecting large-scale genotypic data on major depression. By utilizing the self-report data on major depression from 23andMe, we were able to identify SNPs at a genome-wide level of significance associated with risk for depression in a cohort of European descent. Through a meta-analysis of the 23andMe data with PGC MDD GWAS and a joint-analysis with an independent 23andMe replication cohort, we identify 17 independent SNPs significantly associated with diagnosis of major depression. Through tissue and geneset enrichment analysis utilizing DEPICT, we find that these SNPs are predicted to be enriched in genes expressed in the CNS and function in transcriptional regulation related to neurodevelopment. We find no robust evidence for sex-specificity among our top results but this study combined both genders and only adjusted for sex as a covariate, and was therefore not structured to identify sex-specific loci. This would ideally be done through a sex-stratified GWAS.
