Childhood trauma has life-long effect on genes and the brain

McGill University and Douglas Institute scientists have discovered that childhood trauma can actually alter your DNA and shape the way your genes work. This confirms in humans earlier findings in rats, that maternal care plays a significant role in influencing the genes that control our stress response.

Using a sample of 36 brains; 12 suicide victims who were abused; 12 suicide victims who were not abused and 12 controls, the researchers discovered different epigenetic markings in the brains of the abused group. These markings influence the hypothalamic-pituitary-adrenal (HPA) function, a stress-response which increases the risk of suicide.

This research builds upon findings published last May that showed how child abuse can leave epigenetic marks on DNA. The all-McGill study is set to be published in the February 22, issue of the journal Nature Neuroscience.

“We know from clinical experience that a difficult childhood can have an impact on the course of a person’s life”, said Dr. Turecki.

“Now we are starting to understand the biological implications of such psychological abuse,” added Dr. Szyf.

“The function of our DNA is not as fixed as previously believed, said Dr. Meaney. “The interaction between the environment and the DNA plays a crucial role in determining our resistance to stress thus the risk for suicide. Epigenetic marks are the product of this interaction.”

The researchers discovered that maternal care influences hypothalamic-pituitary-adrenal (HPA) function in the rat through epigenetic programming of certain receptors in the brain. In humans, child abuse alters HPA stress responses and increases the risk for suicide.

In previous studies in laboratory rats, the group proved that simple maternal behavior such as mothers who licked their pups during early childhood has a profound effect on the epigenetic marks on specific genes and effects on behavior in ways that are sustained throughout life. However, these effects on gene expression and stress responses can also be reversed in adult life through treatments known to affect the epigenetic mark known as DNA methylation.

The brain samples in the latest study came from the Quebec Suicide Brain Bank, administered by Dr. Turecki of the Douglas Mental Health University Institute. Research carried out on brain tissue can help develop intervention and prevention programs to help people suffering mental distress and who are at risk of committing suicide.

The research was funded by the Canadian Institutes for Health Research and the National Institute of Child Health and Development (USA).

Bonnie - once again, epigenetics is at the forefront of science. Harmonizing our epigenetic modifiers are becoming the major preventative key.