Evidence of biological process that embeds social experience in DNA that affects entire networks of genes

(Medical Xpress)—Early life experience results in a broad change in the way our DNA is "epigenetically" chemically marked in the brain by a coat of small chemicals called methyl groups, according to researchers at McGill University. A group of researchers led by Prof. Moshe Szyf, a professor of Pharmacology and Therapeutics in the Faculty of Medicine, and research scientists at the Douglas Institute have discovered a remarkable similarity in the way the DNA in human brains and the DNA in animal brains respond to early life adversity. The finding suggests an evolutionary conserved mechanism of response to early life adversity affecting a large number of genes in the genome. 

The research was published in a special volume of , "Biological Embedding of Early Social Adversity:  From Fruit Flies to Kindergartners," and confirms a biological process that embeds social experience in DNA in the brain and that affects not just a few genes but entire networks of genes. "Our data highlights the immense importance of the social environment during childhood and illustrates the profound consequences of child adversity on the way our DNA is programmed," says Szyf, a fellow of the Canadian Institute for Advanced Research (CIFAR).   

Szyf and his coauthors examined differences in the way DNA is marked by methylation in the hippocampal region of the brain of humans who experienced abuse as children and non-abused controls, using samples from The Douglas – Bell Canada Brain Bank directed by Prof. Gustavo Turecki of the Douglas Mental Health University Institute. The human samples were compared to rats who received different early in life. Remarkably, changes that were associated with differences in early were detected in many similar genes in both species.

Although it has been known that early life experiences, particularly social experiences, have long-term impacts on future physical and mental health well-being, it was difficult to understand how these adversities were "embedded" biologically. While previous McGill studies had shown that a few candidate genes could be "epigenetically" marked by early life experiences, it was clear that early life experience had a profound impact on health that couldn't be explained by these few genes.

"This study provides strong evidence of a biological process that embeds in DNA in the brain that affects not just a few genes but entire networks of genes," says Szyf. "We highlighted the immense importance of the social environment during childhood and illustrated the profound consequences of child adversity on the way our DNA is programmed.  Because of our new findings, we now have a broader understanding of how to prevent and treat mental and physical health challenges".

More information: "Conserved epigenetic sensitivity to early life experience in the rat and human hippocampus" is published in a special volume of the Proceedings of the National Academy of Sciences: Biological Embedding of Early Social Adversity: From Fruit Flies to Kindergartners, authored largely by researchers of the Canadian Institute for Advanced Research (CIFAR). This volume sets out an emerging new field of the developmental science of childhood adversity.

Related Stories

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

Feb 23, 2009

(PhysOrg.com) -- 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 ...

Parents' stress leaves lasting marks on children's genes

Aug 30, 2011

Researchers at the University of British Columbia and the Child & Family Research Institute have shown that parental stress during their children's early years can leave an imprint on their sons' or daughters' genes – ...

Childhood adversity may promote cellular aging

Mar 16, 2010

Children who suffer physical or emotional abuse could be faced with accelerated cellular aging as adults, according to new research published by Elsevier in Biological Psychiatry.

Recommended for you

New research software automates DNA analysis

Oct 20, 2014

At the core of medical research is problem-solving, which is exactly what two PhD scientists did when they set out to eliminate a common, time-consuming task performed in research laboratories around the world.

User comments