It doesn’t come as a surprise that childhood abuse has long term effects that show itself way into adulthood. Adults with a history of childhood abuse are known to have higher risks of psychological problems and difficulty responding to stress. But a recent study found that abuse in early childhood can permanently change how certain genes in the brain work, so much, that the risk of suicide is increased.

A Canadian study led by Michael Meaney examined the gene for glucocorticoid receptor – which controls a brain’s response to stress – in 12 suicide victims with a history of abuse, and another 12 who did not suffer abuse as children.

The researchers found that those who have been abused as children produced chemical changes in the brain which reduced the gene’s activity, and in turn resulted in the victim’s abnormally heightened response to stress.

The traumatic childhood experiences changed the gene expression and not the gene itself, so future studies could focus on whether drugs can reverse such effects, adds Meaney.

Read more about study in – Child abuse ‘impacts stress gene’.

The study was e-published at Nature Neuroscience (Epigenetic regulation of the glucocorticoid receptor in human brain associates with childhood abuse. Published online: 22 February 2009)

An interesting article on the suicidal brain came out of Biological Psychiatry this week - A gene for neurotransmitter reception is shut down in the suicidal brain.

Scientists found chemical changes relating to regulation of cell development were happening in the brains of people with major depressive disorder who committed suicide. The gene controlling neurotransmitter reception plays a role in regulating behavior. It’s very interesting. Without proper regulation of behavior, then I assume the behavior would be erratic and contribute to suicidal tendencies.

This is another example of epigenetics at work. Without even changing the DNA structure, environment can cause heritable changes in gene function. In this case, depression triggers the brain

via medical news today

Researchers have found marked genetic differences between brains of men who committed suicide and the brains of men who did not. Of those individuals studied, all had been victims of child abuse.

Even though the genetic sequence was the same in the suicide and non-suicide brains, researchers at the McGill University, Montreal, Quebec, led by Moshe Szyfa, discovered that epigenetic markings were different. That is, the researchers noted a chemical coating on genes that was influenced by environmental factors. In this unique study, the DNA of male suicide victims from Quebec was analysed. The 13 people who committed suicide all had been victims of child abuse.

“It’s possible the changes in epigenetic markers were caused by the exposure to childhood abuse, although in humans it’s difficult to establish causality between early childhood and epigenetic markers, in the way we have established this in animal subjects,”said Szyfa. “The big remaining questions are whether scientists could detect similar changes in blood DNA - which could lead to diagnostic tests - and whether we could design interventions to erase these differences in epigenetic markings”

“Our data are merely consistent with the hypothesis that early life events can alter the epigenetic status of genes that mediate neural functions, and thus contribute to individual differences in the risk for suicide,” conclude the authors.

For further information, click on the following link

http://www.plosone.org/article/fetchArticle.action?articleURI=info:doi/10.1371/journal.pone.0002085

Elaine Warburton  www.geneticsandhealth.com