Genes targeted as contributing to risk of suicide
Johns Hopkins researchers found four genes in a small region of chromosomes that determine who is at highest risk for suicide. They say the findings could lead to targeted research and drug development. The genes lie within a small region of chromosome 2 that the scientists explain contains one gene in particular found in higher levels among people who have committed suicide.
“We have long believed that genes play a role in what makes the difference between thinking about suicide and actually doing it”, explains lead study author study Virginia L. Willour, Ph.D., an assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine says,
ACPI protein higher in people who commit suicide
The ACPI - acid cysteine proteinase inhibitor – gene is included in the four genes targeted for increased risk of suicide by the researchers. The ACPI protein acts the same way as lithium given to patients to lower rates of suicidal behavior.
The researchers studied DNA in 2,700 adults with bipolar disorder to find those who had one copy of a genetic variant in the chromosome 2 area where ACPI is located were 1.4 time more likely to attempt suicide. Two copies of the gene tripled the chances of attempted suicide. Among the group studied, 1,201 had a history of suicide attempts and 1,497 were without.
In a second study of DNA, the scientists came up with the same results. This time they looked at samples from more than 3,000 people with bipolar disorder. The researchers say using DNA only from those with bipolar disorder allows them to control for mental illness and focus on why one group can control suicidal urges while another group is at higher risk for attempting suicide.
“What’s promising are the implications of this work for learning more about the biology of suicide and the medications used to treat patients who may be at risk,” Willour says. “Not everyone with bipolar disorder can take lithium because of its side effects. If we could give them another option, that would be fantastic.”
According to the Willour, suicide kills 1.4 percent of the U.S. population and forty-seven percent of people with bipolar disorder contemplate suicide, but just 25 percent actually do it. In general, 4.6 percent of the population has attempted suicide at least once. The new study suggests identifying genes that play a role in who is at highest risk for suicide could mean better treatment options.
Source: Johns Hopkins Medicine