A team of McGill University scientists has found that suicide victims who were abused as children have clear genetic changes in their brains.

During the study, researchers discovered what they say are key differences between the brains of ordinary people, and of those who took their own lives after suffering child abuse.

They found that the genetic sequence wasn't significantly different in the suicide and non-suicide brains, but there were differences in their epigenetic marking - a chemical coating influenced by environmental factors.

Researchers found that all of the 13 suicide victims in the study had experienced abuse as children.

"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 Moshe Szyf, a professor in McGill's Department of Pharmacology and
Therapeutics.

"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," he added.

Szyf and his colleagues built on their world-renowned epigenetics work to uncover differences in the DNA in the brains of a group of male suicide victims from Quebec.

Epigenetics is the study of changes in the function of genes that don't involve changes in the sequences of DNA.

That sequence is inherited and remains fixed throughout life and is identical in every part of the body.

However, during gestation, the DNA acquired a chemical coating called methylation.