A study carried out at the University of British Columbia and Harvard University suggests that childhood trauma can have adverse genetic effects and actually damage our DNA (although it is not yet known if these genetic alterations can be passed on to the next generation and more research is necessary before that question can be answered).
These changes have been described as ‘molecular scars’ and the process that causes these scars are known as ‘tagging’ or, more technically, DNA methylation (a biological process that alters DNA molecules by the addition of methyl groups which can alter how the DNA segment functions including whether it is ‘switched on’ or ‘switched off.’).
The study involved 34 adult men, 17 of whom had experienced physical abuse in childhood and 2 of whom had experienced sexual abuse.
It was found that, of the 34 men who participated in the study, the 19 who had suffered childhood trauma had, on average, signs of about 20 to 25 percent more tagging than those who had not been abused, a difference that was highly significant.
Gladish, the lead researcher, suggests that such research as this may eventually pave the way toward genetic tests to ascertain whether or not an individual has suffered childhood trauma and also cast light upon the mechanisms by which the experience of childhood trauma makes the individual more susceptible to disease as an adult.
Roberts, A.L., Gladish, N., Gatev, E. et al. Exposure to childhood abuse is associated with human sperm DNA methylation. Transl Psychiatry 8, 194 (2018). https://doi.org/10.1038/s41398-018-0252-1