Featured Research

from universities, journals, and other organizations

Yin And Yang Of Genes For Mood Disorders

Date:
March 17, 2008
Source:
Molecular Psychiatry
Summary:
Individual genes do not cause depression, but they increase the probability of having a depression in the face of other accumulating risk factors, such as other genes and environmental stressors. This study is the first to shows that two genes related to the development of serotonin systems in the brain linked to the experience of negative emotions and to the treatment of depression exaggerate each other's effects on this brain system crucial for depression.

Individual genes do not cause depression, but they are thought to increase the probability of an individual having a depression in the face of other accumulating risk factors, such as other genes and environmental stressors. One gene that has been shown to increase the risk for depression in the context of multiple stressful life events is the gene for the serotonin transporter protein.

This gene is responsible for making the protein that is targeted by all current drug treatments for depression. In a number of studies it has been shown that people who inherit one form of this gene, called SLC6A4, are at up to four times the risk of depression if they experience unusual stresses in their lives. Basic science experiments and imaging studies in normal people suggest that the way this form of the gene affects risk for depression is by impacting on the development of a system in the brain that mediates how negative environmental stresses and threats feel.

The effects of this serotonin gene on this brain system are thought to occur early in development, where the shaping of brain systems related to how the environment is experienced emotionally is critically determined.

Basic science experiments have shown that another gene, called BDNF, regulates the expression of a protein that is important for the ability of the serotonin gene to cause these developmental effects.

The BNDF gene plays a critical role in allowing the serotonin gene to have its affect on brain development. Interestingly, the BDNF gene also has been found to be a risk factor for mood disorders and is thought to be important in mediating the effects of antidepressant drugs. Thus, given the basic molecular link between SLC56A4 and BDNF, and the potential that risk for depression might be better understood in the context of these two genes together rather than any one of them alone, investigators now have looked at how inheriting different combinations of forms of these two gene would impact on the development of this emotion regulation system in the brain.

They found that in normal subjects the deleterious impact of the serotonin gene on the development of this brain system was critically dependent on which form of the BDNF gene was also inherited. If an individual inherited one form of the BDNF gene, they were particularly susceptible to the deleterious form of the serotonin gene but if they inherited the other form of the BDNF gene, they were completely protected against it.

This study is the first to show the complex interactions that occur between mood disorder related genes and their impact on mood disorder related brain circuitry. The study makes it clear that individual genes have to be viewed in a context, both a genetic and an environmental context. But the results also illustrate that no one gene is an island unto itself, and the impact that any gene will have on complex condition like mental illnesses will depend on how that gene interacts with other genes sharing biological overlap.

This study also makes it clear why individuals genes do not show stronger effects on predicting complex illnesss like depression, because risk is based on the combinatorial effects of interacting risk factors.

Citation source: Molecular Psychiatry advance online publication 12 March 2008


Story Source:

The above story is based on materials provided by Molecular Psychiatry. Note: Materials may be edited for content and length.


Cite This Page:

Molecular Psychiatry. "Yin And Yang Of Genes For Mood Disorders." ScienceDaily. ScienceDaily, 17 March 2008. <www.sciencedaily.com/releases/2008/03/080312172620.htm>.
Molecular Psychiatry. (2008, March 17). Yin And Yang Of Genes For Mood Disorders. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/2008/03/080312172620.htm
Molecular Psychiatry. "Yin And Yang Of Genes For Mood Disorders." ScienceDaily. www.sciencedaily.com/releases/2008/03/080312172620.htm (accessed August 28, 2014).

Share This




More Health & Medicine News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Mini Pacemaker Has No Wires

Mini Pacemaker Has No Wires

Ivanhoe (Aug. 27, 2014) Cardiac experts are testing a new experimental device designed to eliminate major surgery and still keep the heart on track. Video provided by Ivanhoe
Powered by NewsLook.com
After Cancer: Rebuilding Breasts With Fat

After Cancer: Rebuilding Breasts With Fat

Ivanhoe (Aug. 27, 2014) More than 269 million women are diagnosed with breast cancer each year. Many of them will need surgery and radiation, but there’s a new simple way to reconstruct tissue using a patient’s own fat. Video provided by Ivanhoe
Powered by NewsLook.com
Blood Clots in Kids

Blood Clots in Kids

Ivanhoe (Aug. 27, 2014) Every year, up to 200,000 Americans die from a blood clot that travels to their lungs. You’ve heard about clots in adults, but new research shows kids can get them too. Video provided by Ivanhoe
Powered by NewsLook.com
Radio Waves Knock out Knee Pain

Radio Waves Knock out Knee Pain

Ivanhoe (Aug. 27, 2014) Doctors have used radio frequency ablation or RFA to reduce neck and back pain for years. But now, that same technique is providing longer-term relief for patients with severe knee pain. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins