Meta-Analyses of Genome-Wide Association Studies for Postpartum Depression.

Objective: Postpartum depression (PPD) is a common subtype of major depressive disorder (MDD) that is more heritable, yet is understudied in psychiatric genetics. The authors conducted meta-analyses of genome-wide association studies (GWASs) to investigate the genetic architecture of PPD.
Method: Meta-analyses were conducted on 18 cohorts of European ancestry (17,339 PPD cases and 53,426 controls), one cohort of East Asian ancestry (975 cases and 3,780 controls), and one cohort of African ancestry (456 cases and 1,255 controls), totaling 18,770 PPD cases and 58,461 controls. Post-GWAS analyses included 1) single-nucleotide polymorphism (SNP)-based heritability ([Formula: see text]), 2) genetic correlations between PPD and other phenotypes, and 3) enrichment of the PPD GWAS findings in 27 human tissues and 265 cell types from the mouse central and peripheral nervous system.
Results: No SNP achieved genome-wide significance in the European or the trans-ancestry meta-analyses. The [Formula: see text] of PPD was 0.14 (SE=0.02). Significant genetic correlations were estimated for PPD with MDD, bipolar disorder, anxiety disorders, posttraumatic stress disorder, insomnia, age at menarche, and polycystic ovary syndrome. Cell-type enrichment analyses implicate inhibitory neurons in the thalamus and cholinergic neurons within septal nuclei of the hypothalamus, a pattern that differs from MDD.
Conclusions: While more samples are needed to reach genome-wide levels of significance, the results presented confirm PPD as a polygenic and heritable phenotype. There is also evidence that despite a high correlation with MDD, PPD may have unique genetic components. Cell enrichment results suggest GABAergic neurons, which converge on a common mechanism with the only medication approved by the U.S. Food and Drug Administration for PPD (brexanolone).
Competing Interests: Dr. Choi has received an honorarium from Depression and Anxiety for service as Deputy Editor. Dr. Raffield has served as a consultant for the TOPMed Administrative Coordinating Center (through Westat). Dr. Andreassen has received speaking honoraria from Janssen, Lundbeck, and Sunovion, and he has served as a consultant for Cortechs.ai and HealthLytix. Dr. Frey has received research support from MediPharm and Janssen. Dr. Grigoriadis has received royalties from the Canadian Pharmacists Association, Norton, and UpToDate. Dr. Jones has received grant funding from Takeda and Akrivia health. Dr. Kennedy has served as a scientific advisory board member for Myriad Neuroscience. Dr. McIntosh has served as a speaker for Illumina and Janssen. Dr. Munk-Olsen has served as a speaker for Lundbeck. Dr. Rubinow has received research funding from the Buszucki Foundation, NIH, and Sage Therapeutics; he serves on scientific advisory boards for the Foundation of Hope, Sage Therapeutics, and Sensorium Therapeutics and on clinical advisory boards for EmbarkNeuro and Felicity Pharma; he has served as a consultant for Aldeyra Therapeutics, Arrivo Bioventures, Brii Biosciences, and GH Research–Ireland; and he has stock options from Sage Therapeutics and Sensorium Therapeutics. Dr. Skalkidou has served as a consultant for Biogen; she receives compensation for lectures and organization of courses in reproductive endocrinology; and she is a shareholder and serves on the board of Svensk Telepsykiatri. Dr. Smoller has served on a scientific advisory board for Sensorium Therapeutics; he has received grant support from Biogen; and he is principal investigator of a collaborative study of the genetics of depression and bipolar disorder sponsored by 23andMe, for which 23andMe provides analysis time as in-kind support but no payments. Dr. Stein has received personal fees from Discovery Vitality, Johnson & Johnson, Kanna, L'Oreal, Lundbeck, Orion, Sanofi, Servier, Takeda, and Vistagen. Dr. Stowe has served on scientific advisory boards for Sage Therapeutics and Reunion Neuroscience. Dr. Taylor has given a lecture for AbbVie. Dr. Vigod has received royalties from UpToDate. Dr. Zar has received funding from the Bill and Melinda Gates Foundation. Dr. Meltzer-Brody has received sponsored research grant funding from Sage Therapeutics; she has served as a consultant for EmbarkNeuro and the Neuroscience Education Institute; and she serves as a professional corporation owner for Modern Health. Dr. Sullivan has served as an adviser for, and is a shareholder in, Neumora Therapeutics. The other authors report no financial relationships with commercial interests.