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The marks of trauma are deep and long-lasting.
The psychological wounds it leaves may lead to health issues; trauma in early childhood can lead to health woes in adulthood. It also may lead to changes in how a gene is expressed, leaving a marker on your DNA, a physical sign of how your body responded to an event.
Those markers can be measured. And according to a study by Virginia Commonwealth University School of Pharmacy researchers, the development of a tool that could help identify the markers in children, who are susceptible to developing significant adverse conditions later in life, would allow them to mitigate poor outcomes earlier.
“By looking at DNA responses associated with trauma, we’ve developed a novel tool for predicting long-term health risks,” according to a statement from Dr. Edwin Van den Oord, director of the Center for Biomarker Research and Precision Medicine at the VCU School of Pharmacy and lead author on the study.
The study was featured in the August issue of Molecular Psychiatry and conducted with a $3.5 million grant through the National Institute of Mental Health. It was based on an analysis of data and blood samples from a study of children and teens in North Carolina that began in 1992. The Great Smoky Mountain Study, by Duke University and the North Carolina Department of Health and Human Services, started with many of the children when they were ages 9 to 13 and continued into their 30s.
Dr. Edwin Van den Oord (Photo courtesy VCU Health)
Van den Oord’s group reviewed DNA samples collected during the Duke survey in a longitudinal study to look at DNA responses, known as methylation, from trauma in childhood and use that information to assess its use in predicting psychiatric disorders including depression or substance abuse, and other adverse outcomes such as poverty that may be evident years later. Risk scores were developed in the assessment, and those scores were an effective predictor of later health woes.
Van den Oord notes that methylation is relatively easy to study.
Methylation captures genetic changes stemming from trauma and may be useful in predicting who is susceptible and is more effective than self-reporting. Not only does it show that a child was traumatized, but also how the person responded, according to Van den Oord. Since it’s a biomarker, it’s a physical one that’s available through a blood sample, which could prove useful in children who are unable to talk about a traumatic event or in incidents of neglect or sexual abuse.
“[It’s] so spectacular that it performed so well,” he says.
Van den Oord says that a logical next step would be to review a similar data set for comparison to determine if similar outcomes would be observed. That could be problematic, since the data studied was from a unique longitudinal research effort that continued for 20-30 years. It would require another grant for the work.
“We need to get back into the lab,” he says.
About Epigenetics
First Things First
Your epigenome is made up of chemical compounds that regulate your genome (your set of genes/genetic material). Epigenetics is the study of how genes may be affected by behavior (such as your physical activity) or environment (such as toxins or what you eat). Changes also occur during development and aging. Since environmental factors may affect gene expression, individual response is unique; even identical twins may have different outcomes in health and behavior.
What Happens
These factors can affect how a gene is expressed, whether it’s turned on or off. It has no impact on your genetic sequence, and these changes in how a gene is expressed may be reversible. Your epigenome changes throughout life through factors such as smoking or disease that lead to chemical responses and damage the epigenome. The ability of the epigenome to adjust to various life events is crucial to health but may also lead to adverse impacts.
This Study
One way changes in gene expression can be tracked is monitoring DNA methylation, a type of epigenetic change in which a chemical group (a methyl group) is added to specific sites on DNA, where it blocks proteins that would attach and essentially turns off the gene. Removal of the chemical group is called demethylation, which would turn on a gene. Blood samples were used and numbers were crunched to assess methylation in DNA at some 28 million sites. Changes in methylation were then identified that correlated with reports of trauma, from serious injury to sexual violence. Researchers used machine learning on the data to generate risk scores, which proved predictive in assessing adverse health outcomes that occurred years after childhood trauma.
Sources: Centers for Disease Control and Prevention, National Human Genome Research Institute, Virginia Commonwealth University
