Featured Research

from universities, journals, and other organizations

Scientists Identify A Candidate Gene For Osteoporosis

Date:
March 29, 2007
Source:
Cold Spring Harbor Laboratory
Summary:
Researchers report the identification of a gene that may play a role in susceptibility to osteoporosis -- the crippling disease that leads to bone fractures, especially of the hip and spine. The study shows convincing evidence that a gene called DARC negatively regulates bone density in mice.

Researchers report the identification of a gene that may play a role in susceptibility to osteoporosis--the crippling disease that leads to bone fractures, especially of the hip and spine. The study, conducted by scientists at the Musculoskeletal Diseases Center of the Jerry L Pettis Memorial Veteran's Affairs Medical Center at Loma Linda, shows convincing evidence that a gene called DARC negatively regulates bone density in mice. The report appears online in Genome Research.

"If our finding using the mouse model is confirmed in humans, then we may be able to develop therapies that are based on inhibiting the function of the DARC gene," explains Dr. Subburaman Mohan, Ph.D., a Senior Scientist at the Loma Linda VA Medical Center and a Professor of Medicine and Biochemistry at Loma Linda University. "We will also be able to develop genetic screens to identify individuals who are at risk for osteoporosis."

According to the National Osteoporosis Foundation, osteoporosis affects 55% of Americans over the age of 50. Low bone mineral density (BMD)--the primary indicator of osteoporosis--is influenced by both genetic and environmental factors (e.g., diet or medication). But the genetic element has been difficult to characterize because bone growth is controlled by many genes, including those for various hormones, growth factors, signaling molecules, and structural components of bone and cartilage.

Previous genetic studies had pointed to a region on mouse chromosome 1 as containing a gene responsible for BMD regulation. In the current project, Mohan and his colleagues honed in on this region of chromosome 1 using a variety of molecular techniques, and they located a gene called DARC (Duffy Antigen Receptor for Chemokines) that exhibited different levels of expression in mice with higher BMD. The analogous chromosomal region has also been shown to influence osteoporosis in humans.

The protein encoded by DARC binds to chemokines--or small signaling proteins--that are involved in osteoclast formation. Osteoclasts break down bone in a process called bone resorption, releasing important minerals such as calcium, phosphate, and magnesium into the bloodstream. This causes a reduction in BMD.

To confirm the involvement of DARC in regulating BMD, Mohan's team characterized the skeletal phenotype of mice with and without the DARC gene. The DARC-knockout mice exhibited increased BMD and lower bone resorption compared to mice with the DARC gene, supporting the predicted role of DARC in hastening bone resorption. They also showed that antibodies to the DARC protein, which effectively blocked the action of DARC, inhibited the formation of osteoclasts.

Although the researchers have identified a number of DNA alterations in the DARC gene, they did not pinpoint the specific alteration that was responsible for the BMD differences between the two strains of mice. However, Mohan and his colleagues predict that changes in the amino acid sequence or alterations in regulatory regions of the DARC gene may lead to key functional changes.

"There are interesting differences between African Americans and Caucasians that could be associated with this gene," explains Mohan. "African Americans exhibit significantly higher BMD compared to Caucasians. Also, African Americans generally do not have the Duffy protein on red blood cells, while Caucasians do. The potential genetic association between DARC gene variation and these traits in humans certainly makes it worthy of further investigation."


Story Source:

The above story is based on materials provided by Cold Spring Harbor Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Cold Spring Harbor Laboratory. "Scientists Identify A Candidate Gene For Osteoporosis." ScienceDaily. ScienceDaily, 29 March 2007. <www.sciencedaily.com/releases/2007/03/070329075351.htm>.
Cold Spring Harbor Laboratory. (2007, March 29). Scientists Identify A Candidate Gene For Osteoporosis. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2007/03/070329075351.htm
Cold Spring Harbor Laboratory. "Scientists Identify A Candidate Gene For Osteoporosis." ScienceDaily. www.sciencedaily.com/releases/2007/03/070329075351.htm (accessed September 2, 2014).

Share This




More Health & Medicine News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
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