“We’re hoping our findings will eventually lead to tests that can identify those at high risk for attempting suicide,” says Virginia Willour, Ph.D., an assistant professor in the Department of Psychiatry at the Johns Hopkins University School of Medicine and lead author of the study. An estimated 4.6 percent of Americans ages 15 to 54 have tried to take their lives, according to Willour.
The investigators conducted a family linkage study in which they searched for commonalities in the genomes of family members with bipolar disorder and a history of attempted suicide. The same gene region on chromosome 2 that was identified by this bipolar disorder and attempted suicide study was recently identified by two complementary family studies that looked at attempted suicide in families with major depression and alcohol dependence.
“Family linkage studies are not always consistent, so the fact that all three studies, including ours, point to the same region of the genome is a good indication that we are on the right track toward identifying a gene or genes that play a role in why a person chooses to take his or her own life,” says Willour.
In the multi-institutional study, results of which appear in the March issue of Biological Psychiatry, the researchers examined data from 162 families with bipolar disorder. They looked at attempted suicide in this sample because it is an important clinical problem that tends to occur more often in some of these families than in others, suggesting a distinctive genetic basis, according to senior author James B. Potash, M.D., M.P.H., of the Department of Psychiatry at Hopkins. This technique, of looking at sub-types of illness, is used by genetic researchers as a way to reduce genetic complexity.
From the 162 families, the researchers selected 417 subjects who were diagnosed with schizoaffective/bipolar disorder, bipolar I disorder or bipolar II disorder.
These subjects were asked whether they had ever attempted suicide and the degree of intent of the most serious attempt. One hundred fifty-four subjects said they had attempted suicide, and 122 stated that they had “definite” intent. For the purpose of this study, the latter were considered to have a history of attempted suicide.
Data for all 417 subjects was entered into a computer program that looks for genetic similarities between subjects with similar psychological profiles. Results indicated that family members with a history of attempted suicide and bipolar disorder showed a high degree of genetic similarity at a specific area -- DNA marker D2S1777 -- on a section of chromosome 2 referred to as 2p12. This is the same marker implicated in a 2004 study from the University of Pittsburgh School of Medicine that looked at attempted suicide and major depression. And it is close to another marker, D2S1790, located in the 2p11 region of chromosome 2, which was identified in a 2004 study from the University of Connecticut School of Medicine that looked at alcoholism and attempted suicide.
Willour says that although the Hopkins-led study does not pinpoint a specific gene responsible for attempted suicide, it does suggest a “neighborhood” in which the gene might be found. She adds that the next step is to further narrow the search and find the “address.” “Once we have located the specific gene,” she says, “we can better identify people who might be at risk of suicide and offer drug companies a target for possible therapies.”
The data used by Willour and her team -- DNA samples, medical histories and psychiatric evaluations -- came from an independent study, CHIP, conducted at the University of Chicago, Johns Hopkins, and the National Institute of Mental Health (NIMH) Intramural Program. The purpose of CHIP, initiated in 1988 and funded through at least 2010, is to find genes that predispose people to developing bipolar disorder or particular subtypes of the illness.
Eric Vohr | EurekAlert!
Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)
The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research