It is estimated that between 10 and 20 million people a year try and kill themselves with around one million succeeding. Previous studies have shown that there is a genetic influence on suicide and that suicides tend to cluster in families. Researchers from the Max Planck Institute of Psychiatry in Munich studied three different groups of people in an attempt to find genes that might be associated with an increased risk of suicide. They studied 760 people in Germany. 394 of them were depressed of whom 113 had tried to kill themselves. They also studied another 744 German people being treated for depression, 152 of whom had attempted suicide. Finally they studied 921 African Americans who were attending a clinic for physical health problems - 119 of them had attempted suicide. The researchers found five genetic variations that were associated with an increased risk of suicide. For people with the three most significant variations there was a 4.5x greater risk of attempting suicide.
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