Experiencing community and domestic violence is associated with epigenetic changes in DNA methylation of BDNF and CLPX in adolescents.

Experiencing violence changes behavior, shapes personalities, and poses a risk factor for mental disorders. This association might be mediated through epigenetic modifications that affect gene expression, such as DNA methylation. The present study investigated the impact of community and domestic violence on DNA methylation measured in saliva collected from 375 individuals including three generations: grandmothers (n = 126), mothers (n = 125), and adolescents (n = 124, 53% female). Using the Infinium HumanMethylation450 BeadChip array, in adolescents, we detected two CpG sites that showed an association of DNA methylation and lifetime exposure to community and domestic violence even after FDR correction: BDNF_cg06260077 (logFC -0.454, p = 3.71E-07), and CLPX_cg01908660 (logFC = -0.372, p = 1.38E-07). Differential DNA methylation of the CpG BDNF_cg06260077 associated with exposure to violence was also observed in the maternal but not the grandmaternal generation. BDNF (brain-derived neurotrophic factor) and CLPX (caseinolytic mitochondrial matrix peptidase chaperone subunit) genes are involved in neural development. Our results thus reveal altered molecular mechanisms of developmental and intergenerational trajectories in survivors of repeated violent experiences.