Is There a Suicide Gene?
I recently read an interesting study regarding the “possible” discovery of a genetic link to suicide in patients with bipolar disorder. Is suicide genetic? Is there a suicide gene? Geneticists are making some very interesting discoveries in the links between genetics and mental health. This article appeared in the Psychiatric News May 20, 2011 and was written by Joan Arehart-Treichel. The study was funded by the National Institute of Mental Health and the American Foundation for Suicidal Prevention. The study seems to imply that there is a gene that contributes to suicidal behavior that may have been found. If so, as with the goal of all genetic discoveries, there may be a preventative medication on the way. Also, this may open the door to further discoveries in the genetic grounding of bipolar disorder and suicidal behavior. This article regarding a genetic link to suicide is quite preliminary in its findings and it suggests that further investigations into its discoveries are warranted.
Some of the genes that might fit into this category are the serotonin transporter gene, the tryptophan hydroxylase genes, and hypothalamus-pituitary-adrenal axis genes. The latest gene that has been identified as an independent contributor to suicidal behavior is called the ACP1 gene and is located on chromosome 2 in the region known as 2p25. The study compared the genetic material of 1,200 patients with bipolar disorder with a history of suicidal attempts, to 1,500 patients with bipolar disorder without suicidal attempts. The results of the study found the ACP1 gene in those with the suicidal history; and this gene was not present in the DNA of the other group.
After this finding the researchers went on to examine the brains of 14 individuals who had been diagnosed with bipolar disorder and died of suicide; and 20 brains of those diagnosed with bipolar disorder that had died from other causes. The expression of the ACP1 gene was significantly higher among the 14 individuals who had died of suicide.
Another contributing factor associated with this study is that the ACP1 gene influences a biological pathway that is regulated by lithium. Lithium’s ability to reduce suicidal behavior has been well established within the psychiatric community. It is supposed that this ACP1 gene may increase compulsive-aggressive behavior which might increase the risk of suicidal behavior. These conclusions have given enough evidence to pursue further studies on a genetic link to suicide.
Suicide seems to run in families – does this imply a genetic link?
Suicidal behavior is not merely a genetic issue even if indeed a genetic link is conclusively established. We know that with family members that have committed suicide seem to have a higher risk of suicide themselves. Whether this is a genetic link to suicide or a psychological basis is somewhat moot in that both groups should be on the alert for a predisposition to suicide.