Epigenetic Mediation of Early Environmental Influences on Adolescent Neurobehavioral Development

Although most children navigate the challenges of puberty and settle into adolescence without major problems, about 20% will experience at least one mental health disorder during their teenage years.  Why do some adolescents struggle so much more than others?  Decades of research in developmental science have demonstrated the mutual influence of genotype and early environment on adolescent adjustment, but we still know very little regarding how genes and environments interact at the neurobiological level to produce risk for disorder.  Mounting evidence suggests that one pathway by which early experience “gets under the skin” is by altering patterns of gene activity – that is, by triggering epigenetic changes.  For children with highly susceptible genotypes, early exposure to harsh environmental conditions is thought to trigger long-lasting epigenetic changes to the brain’s stress response system that may increase vulnerability to psychopathology.

Although this broad conceptual model is well-supported by experimental research using animal models, epigenetic studies of human brain development are rare. This project adds measures of DNA methylation to two studies of adolescent development with rich existing measures of early environment, genes, brain, and behavior: (a) the Parenting Across Cultures (PAC) study, based out of the Center for Child and Family Policy, and (b) the Teen Alcohol Outcomes Study (TAOS),  directed by Doug Williamson at the University of Texas Health Science Center in San Antonio.  Our primary objective is to identify patterns of DNA methylation associated with neural markers of risk for psychopathology.  The long-term goal of this program of research is to elucidate the neurobiological mechanisms underlying genetic and environmental influences on healthy and disordered development.