A single human gene associated with stress may be the secret link researchers have been looking for, in their efforts to predict those prone to committing suicide.

A medical team from Johns Hopkins University say they have discovered a chemical alteration in a single human gene that, if confirmed in future larger studies, may make it possible for doctors to accurately anticipate a person's risk of attempting to kill themselves with a simple blood test, according to a news release.

Described online in The American Journal of Psychiatry, the new findings suggest changes in a gene tied to the brain's response to stress hormones plays a significant role in transforming what might otherwise be an unremarkable reaction to the strain of everyday life into suicidal thoughts and behaviors.

"Suicide is a major preventable public health problem, but we have been stymied in our prevention efforts because we have no consistent way to predict those who are at increased risk of killing themselves," study leader Zachary Kaminsky, an assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, said in the release. "With a test like ours, we may be able to stem suicide rates by identifying those people and intervening early enough to head off a catastrophe."

For the series of experiments he and his colleagues ran, Kaminsky focused on a genetic mutation known as SKA2, the levels of which were significantly reduced in people who had died by suicide.

The SKA2 gene is expressed in the prefrontal cortex of the brain, which is involved in inhibiting negative thoughts and controlling impulsive behavior.

Further, SKA2 is specifically responsible for directing stress hormone receptors toward specific areas of the brain, where they are needed.

Kaminsky explained a test based on these findings might best be used to predict future suicide attempts in those who are ill, to restrict lethal means or methods among those a risk, or to make decisions regarding the intensity of intervention approaches.

He said that such testing could be implemented in the military to test whether members have the gene mutation that makes them more vulnerable. Those at risk could be more closely monitored when they return home after deployment.

A test could also be useful in a psychiatric emergency room, he added, as part of a suicide risk assessment.

"We have found a gene that we think could be really important for consistently identifying a range of behaviors from suicidal thoughts to attempts to completions," Kaminsky said. "We need to study this in a larger sample but we believe that we might be able to monitor the blood to identify those at risk of suicide."