This project was funded by NIHMD (R01MD01172. 8/14/2017-4/30/2021. PI: Darlene Kertes, Co-I: Jinying Zhao). The goal of this study is to examine genome-wide DNA methylation and telomere length (TL) as biological mediators of stress effects on emotional/behavioral health among impoverished African-American (AA) youth, and to test for the moderating role of resilience-enhancing protective factors, sex, and genotype. Aims: (1) determine whether environmental stressors, including racial discrimination, exposure to violence, and neighborhood ecology are associated with DNA methylation and TL, reflective of a biological embedding of stress; (2) examine stress-linked variations in methylation and TL as mediators of stress effects on emotional/behavioral health; (3) identify social environment protective factors, including neighborhood factors, that could potentially buffer impacts of stress on health outcomes, and test for sex differences; (4) explore the role of genotype as a contributing factor to the relations between environmental stress, methylation, TL, and emotional/behavioral health.