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Genetic link to

suicide found

ISLAMABAD: Scientists have discovered a gene which may predispose people to suicide and could lead to the development of tests to identify individuals at risk of killing themselves.

The discovery follows a 10-year study by a team at the Royal Ottawa Hospital into the causes of suicide. The team found that depressed people with a mutation in a gene that encodes for a serotonin 2A receptor Ñ a chemical linked to mood Ñ were more than twice as likely to commit suicide than depressed people without the mutation.

According to the report, in the American Journal of Medical Genetics, depression was not the simple, single reason for their taking their own lives. It was the additional possession of a particular genetic mutation which led them to suicide.

Suicidal tendencies were more frequent in depressed individuals carrying the mutation, said team member Dr Pavel Hrdina.

"This is a warning sign, an early marker. There might be depressed people who would'nt know at the time they had the mutation. Those patients would be more closely watched than others," he said.

The discovery of a gene that might pinpoint, and ultimately help, people predisposed to carry out such acts therefore has the potential to ease human suffering.

However, the discovery also carries considerable moral implications, as do other recently developed genetic tests Ñ such as those that can spot Alzheimers victims years before they develop symptoms.

The Ottawa researchers started their project by analysing the brains of people who had killed themselves in Hungary, a country with one of the world's highest suicide rates. The tests showed large amounts of the mutated gene. The team then carried out a long-term study on a group of 120 depressed Canadians.

"We divided the depressed patients into suicidal and non-suicidal and we found the frequency of the gene variety was significantly higher in the suicidal patients," Hrdina said. "We concluded that the carriers of this particular combination in the gene were at double the risk for suicidal tendencies."

Hrdina said the Royal Ottawa Hospital team was now looking at whether people suffering from other mental disorders, such as schizo phrenia, also carry the mutation.ÑAPP