Genetics Influence Level of Depression Tied to Trauma Exposure, Study Finds

Genetics can influence the development of major depressive disorder (MDD) in affected individuals who were previously exposed to trauma, according to new study appearing in JAMA Psychiatry this week. Self-reported trauma exposure, particularly that occurring in childhood, has an established role in depression, and research has indicated that higher levels of trauma are linked to MDD. However, the interplay between genetics and trauma on depression has not been fully explored. In their new paper, researchers from the University of Edinburgh analyzed genomic and other data on roughly 150,000 adult participants in the UK Biobank who showed depressive symptoms and/or neuroticism and reported exposure to a range of different traumas. They find that genome-by-trauma exposure interactions can explain up to 20 percent of variation in MDD and more often in males versus females. The study results, the authors write, suggest that "exploring mechanisms underlying genome-by-trauma exposure interactions may be useful in identifying at-risk individuals and intervention targets ... [and] may provide explanations for depression prevalence differences across the different sexes."