The relationship between social adversity, micro-RNA expression and post-traumatic stress in a prospective,...

Epigenetic processes serve as both mediators of and responders to social and environmental challenges, influencing biological outcomes. Therefore, pinpointing epigenetic factors associated with social adversity and traumatic stress enables understanding of the mechanisms underlying vulnerability and resilience. We hypothesized that micro-RNA (miRNA) expression may be associated with post-traumatic stress disorder symptom severity in the context of social adversity. To test this hypothesis, we leveraged longitudinal data from the Detroit Neighborhood Health Study, a community-based, prospective cohort of predominantly African Americans. This includes blood-derived RNA samples from 389 participants in wave 2 and 243 participants in wave 4. Social adversity data were available for all included participants (n = 483). Results identified 86 miRNAs that are associated with social adversities (financial difficulties, perceived discrimination, cumulative trauma) and post-traumatic stress severity. These miRNAs are involved primarily in the immune response, brain and neural function, as well as cell cycle and differentiation, and 23 (25%) have previously been associated with conditions related to post-traumatic stress disorder, including traumatic brain injury and stress response. Our findings offer a fresh perspective on understanding the epigenetic role of miRNA in the interaction between social adversity and traumatic stress.