Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists discover genetic marker responsible for two-fold increase in risk of rheumatoid arthritis

24.06.2004


A team of researchers has discovered a genetic variation that doubles the risk for rheumatoid arthritis (RA). The variation, referred to as a single nucleotide polymorphism (SNP, pronounced "snip"), is present in about 28 percent of individuals with rheumatoid arthritis and 17 percent of the general population. This discovery resulted from a collaboration between scientists from the North American Rheumatoid Arthritis Consortium (NARAC), led by Peter K. Gregersen, MD, of the North Shore-Long Island Jewish Research Institute in Manhasset, NY, Celera Diagnostics and Genomics Collaborative, Inc. The team’s findings are being published in the August 2004 issue of the American Journal of Human Genetics.



"This is an important discovery, really a major genetic variant identified in a U.S. study that clearly seems to be involved in rheumatoid arthritis," said Stephen I. Katz, MD, PhD, director of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), the lead agency at the National Institutes of Health (NIH) that supports NARAC.

While scientists still do not know the exact cause of RA, they do know it is an autoimmune disease in which the body’s natural immune system does not function properly and attacks its own healthy joint tissues. This causes inflammation and subsequent joint damage.


The SNP they linked to RA is located in a gene that codes for an enzyme (called PTPN22) that is known to be involved in controlling the activation of immune cells called T cells. Under normal conditions, the enzyme works as a "negative regulator" --- meaning it inactivates a specific signaling molecule, which in turn interrupts the communication lines and keeps immune cells from becoming overactive. In cases where the SNP is present in one or both copies of an individual’s genes for this enzyme, the team found that the negative regulation by this enzyme appears to be inefficient, so that T cells and other immune cells are hyperresponsive, causing increased inflammation and tissue damage.

"This is not an abnormal gene," said Dr. Gregersen. "It is present in a substantial fraction of the normal population, so it’s probably there for a good reason. It may, in fact, help defend against infection." When it comes to the genetics of complex diseases, context is everything. According to Dr. Gregersen, a genetic variant in the setting of certain environments and in the presence of other genes may have harmful effects, whereas the same genetic variant may have beneficial effects in another genetic and environmental context. "So this particular genetic variation may have contributed to the survival of our ancestors. The price we have to pay for that, however, is that some people are modestly predisposed to developing rheumatoid arthritis."

Using state-of-the-art technology developed by Celera Diagnostics, Ann B. Begovich, PhD, director of inflammation at Celera Diagnostics, and her team discovered the PTPN22 association. The technology allowed them -- in a short period of time -- to look at tens of thousands of SNPs in thousands of DNA samples from subjects with RA as well as normal control subjects. The majority of the DNA samples analyzed in this study were carefully collected from families with RA who contributed to the NARAC project. Genomics Collaborative, Inc. provided additional samples.

"This collaboration has enabled us to make a significant contribution to a very complex genetic problem in a relatively short period of time, something that can only be achieved with a team effort," said Dr. Begovich.

The Arthritis Foundation has been an important supporter of NARAC. "This critical discovery is an illustration of the power of public-private partnerships to solve complex issues," said John H. Klippel, MD, the foundation’s president and CEO.

Research has previously shown that autoimmune diseases such as type 1 diabetes, lupus and thyroid disease tend to group in families, but there has been no previous direct genetic connection to explain the phenomenon. Earlier this year, a study published in Nature Genetics linked this same SNP with type 1 diabetes. Subsequent unpublished research by Dr. Gregersen and his colleagues indicates that this particular gene variant may also increase risk for other autoimmune diseases, such as systemic lupus and autoimmune thyroid disease, as well as type 1 diabetes.

"NIH has provided strong scientific and financial support for the North American Rheumatoid Arthritis Consortium over many years, and we are now beginning to see the fruits of this investment," said Dr. Katz. "I expect this discovery will spin off many more advances in the field." In addition to NIAMS, the National Institute of Allergy and Infectious Diseases and the Office of Research on Women’s Health at the NIH also support NARAC.

Christina Verni | EurekAlert!
Further information:
http://www.nshs.edu

More articles from Health and Medicine:

nachricht Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center

nachricht Overdosing on Calcium
19.06.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Creating a new composite fuel for new-generation fast reactors

20.06.2018 | Materials Sciences

Game-changing finding pushes 3D-printing to the molecular limit

20.06.2018 | Materials Sciences

Could this material enable autonomous vehicles to come to market sooner?

20.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>