• Posted October 4, 2023

Largest-Ever Study of Suicide Genetics Gives Clues to Who's at Risk

New research has discovered 12 gene variants that may be tied to an increased risk of attempting suicide.

These genes also may have links with physical and mental health woes, including chronic pain, attention-deficit/hyperactivity disorder (ADHD), lung conditions and heart disease.

The researchers hope this finding, published online Oct. 1 in the American Journal of Psychiatry, will lead to better understanding of the biological causes of suicide.

"Many people who die from suicide have significant health conditions associated with that risk,"said study corresponding author Anna Docherty, an associate professor of psychiatry at the Huntsman Mental Health Institute (HMHI) at the University of Utah. "If we can use genetic information to characterize the health risks of those who attempt suicide, we can better identify those patients who need contact with the mental health care system."

For the study, the investigators analyzed data from 22 different populations, including people of diverse ethnic backgrounds.

What they found wasn't one single gene influencing risk, but the cumulative effect of different genes.

"In psychiatry, we have many tiny genetic effects, but when we account for all of them together, we start to see a real genetic risk signal,"Docherty explained in a university news release.

To assess that risk, the team broke down data from the Million Veteran Program and the International Suicide Genetics Consortium.

That data included nearly 44,000 documented suicide attempts and more than 915,000 ancestry-matched people who served as the study's control group.

After a meta-analysis of the studies uncovered the genetic variants associated with suicide attempt, the team compared these with previously published genetic data on more than 1,000 other health issues.

"That allowed us to look at how genetic risk for suicide overlaps with genetic risk for depression, heart disease and many other risk factors,"Docherty explained. "It showed significant overlap with mental health conditions, but also a lot of physical health conditions, particularly for smoking and lung-related illnesses. This is something we can't necessarily see in medical records of people who die from suicide."

That doesn't mean that someone with one of these health factors is at high risk for attempting suicide, said study co-author Hilary Coon, a professor of psychiatry at HMHI, but genetic predisposition combined with other stressors could increase risk.

Several of the gene variants control processes in cells such as managing cellular stress, repairing damaged DNA and communicating with the immune system, the study authors noted. These are also highly expressed in the brain and are known targets of antipsychotic and antidepressant drugs.

The research only shows an association, but it could open new avenues for assessing and treating risk, the study authors concluded.

"We want to start to explore the biological underpinnings that are common across suicide and these health factors, because that will lead to the most convincing drug targets,"Docherty noted.

More information

The U.S. Centers for Disease Control and Prevention has more facts about suicide.

SOURCE: University of Utah Health, news release, Oct. 1, 2023