Genomic and Environmental Predictors of Psychopathology Under Stress

Abstract

The overarching aim of this dissertation is to investigate independent and joint contributions of genetic factors and social environment in risk of psychopathology under a variety of stressful environments. In Study 1, we capitalize on recent advances in genomic technology and the measurement of social and environmental characteristics in two distinct populations to investigate gene x environment interactions in depressive symptoms. Here, we address the dissertation’s Specific Aim 1: to test gene x environment interactions in predicting psychopathology under stress using polygenic risk scores for major depressive disorder (MDD). In Study 2, we characterize changes in depressive symptoms among frontline healthcare workers during the COVID-19 pandemic, and the associated changes in their work environments. Using causal mediation analysis, we address the dissertation’s Specific Aim 2: to investigate trajectories of depressive symptoms during a global stressor, and identify potential sources of support 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 global psychosocial stressors, and interpersonal and institutional social support as they relate to the development of depressive symptoms.