Children who have been abused may may carry the effects of that trauma in their cells, scientists said on Tuesday in research that could help criminal investigations investigating historic abuse.
The imprints may also shed light on whether or not trauma can be passed on between generations.
A team of researchers at the University of British Columbia examined the sperm cells of 34 adult men, some of whom had been victims of child abuse. They found that the effects of the trauma were indelibly printed in 12 regions of the DNA of those men who had experienced varying levels of emotional, physical or sexual abuse.
Scientists believe these alterations, known as methylation, could one day be used by investigators or courts in historical child abuse cases.
“If you think of genes as being like light bulbs, DNA methylation is like a dimmer switch that controls how strong each light is — which in turn can influence how cells function,” Nicole Gladish, a PhD candidate at the university’s Department of Medical Genetics, told AFP.
“This information can potentially provide additional information about how childhood abuse affects long-term physical and mental health.”
The experiment is one of a growing number of trials looking into what turns genes “on and off” at different periods of human development, a field of study known as epigenetics.
Once thought as entirely pre-programmed from conception, some genes are now known to be activated or deactivated by environmental factors or an individual’s life experience.
Small piece of the puzzle
Scientists involved in the study, published in the journal Translational Psychiatry, said they still did not know how methylation affects a person’s long-term health.
In addition, due to the difficulty in extracting egg cells, the team doesn’t plan to replicate the experiment on women– statistically far likelier to have been victims of child abuse than men.
Scientists said the degree of “dimming” in the DNA regions were surprising–one part of the genome of the men who were abused as children was 29 percent different to those who were not.
And, because the degree of methylation changes over time, they were able to tell by looking at the men’s cells roughly when the abuse occurred.
“This might help the development of tests that could be used by healthcare workers or potentially even as forensic evidence,” Gladish said.