Exposure to childhood adversity (e.g., abuse, poverty) is one of the most potent risk factors for major depression, increasing risk for the disorder in both youth and adults by at least two-fold. However, the mechanisms explaining how adversity creates a vulnerability to depression are poorly understood.

The proposed study seeks to leverage longitudinal data and with insights from genetics, epigenetics, and human development to characterize the mechanisms linking “early life” adversity to risk for depression throughout the lifespan. The project’s overall goal will be to examine whether and how the effects of gene-environment interplay are strongest during sensitive periods in development. Sensitive periods are life stages when the brain is highly “plastic” and when experience can impart enduring effects. These periods are thus high-risk, high-reward stages of human development when toxic exposures, including adversity, are most harmful, but when enriching exposures and interventions could offer greatest benefit

Our specific goal in this project is to test the overarching hypothesis that vulnerability to adolescent- and adult-onset depression begins in the first five years of life and arises through the effects of adversity-induced epigenetic changes during this sensitive period in development. We posit that exposure to adversity during this sensitive period causes persistent epigenetic changes that alter the trajectory of development in ways that increase risk for depression.