Genomic and Environmental Predictors of Psychopathology Under Stress

The overarching aim of this dissertation is to investigate independent and jointcontributions of genetic factors and social environment in risk of psychopathology under avariety of stressful environments. In Study 1, we capitalize on recent advances in genomictechnology and the measurement of social and environmental characteristics in two distinctpopulations to investigate gene x environment interactions in depressive symptoms. Here, weaddress the dissertation’s Specific Aim 1: to test gene x environment interactions in predictingpsychopathology under stress using polygenic risk scores for major depressive disorder (MDD).In Study 2, we characterize changes in depressive symptoms among frontline healthcare workersduring the COVID-19 pandemic, and the associated changes in their work environments. Usingcausal mediation analysis, we address the dissertation’s Specific Aim 2: to investigatetrajectories of depressive symptoms during a global stressor, and identify potential sources ofsupport for future intervention. In both studies, we apply advanced quantitative methods to large,longitudinal datasets to extend the literature on the potential causes of depressive symptoms.Taken together, these studies consider variability at the levels of genetics, individual and globalpsychosocial stressors, and interpersonal and institutional social support as they relate to thedevelopment of depressive symptoms.