Childhood Adversity and Epigenetic Pockmarks
Maltreatment in childhood may have a lasting impact on health through epigenetics. Epigenetics refers to the idea that events and substances in the environment can affect the structure of DNA by adding chemicals (often methyl or acetyl groups) onto DNA and histones (structures around which DNA is wound) in such a way that the DNA is more or less likely to be transcribed and activated to produce new proteins. Thus our DNA is shaped not only by the genetic inheritance we receive from our parents, but also by events in the environment (which do not alter the sequence of DNA but can influence how easily the DNA gets turned on to produce proteins in our bodies.)
A 2013 study by Divya Mehta et al. published in the Proceedings of the National Academy of Sciences analyzed the childhood backgrounds of adult patients with PTSD and found that patients’ profiles of disease-related gene expression and DNA methylation in blood differed greatly depending on whether or not they had experienced abuse in childhood. Adults who had been abused as children were about twice as likely to show patterns of DNA methylation accompanying their PTSD-related changes in gene expression.
The implication of this research is that childhood trauma can leave a kind of epigenetic pockmark on a person’s DNA, affecting the way the DNA produces proteins, potentially for the rest of that person’s life.