Suicide Linked to Gene

TORONTO (AP) — Scientists from the Royal Ottawa Hospital have found a link between a gene mutation and suicide. The discovery, to be published next month in the American Journal of Medical Genetics, may lead to a ``suicide test'' that would identify patients at risk, the National Post reported Friday. Suicide is the world's ninth leading cause of death. The researchers found a mutation in a gene that regulates the brain's level of serotonin, one of the proteins that carries messages between cells. They estimated that the mutation more than doubles the risk of suicidal behavior in those who have it. ``Individuals who carry the (mutation) are at higher risk when a situation that triggers their suicidal tendencies will occur,'' neurobiologist Dr. Pavel Hrdina, who co-wrote the landmark study, told the Post. The study looked only at patients with major depression. It did not examine people who have not been chronically suicidal and may have attempted suicide for what doctors believed was a one-time cry for help. However, the researchers say it's possible the mutation may also be linked to the elevated risk of suicide among schizophrenics. People have long believed that mental illness and suicide are inherited. A diagnostic test for this trait would identify people in need of medical help, including gene therapy.