Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Genetic Link to Dry Macular Degeneration Found

28.08.2008
A University of Kentucky ophthalmologist, along with a team of scientists, has discovered a genetic mutation that offers protection against a type of age-related macular degeneration (AMD), a disease of the eye that is the leading cause of blindness in adults over age 50.

The study, published Wednesday in The New England Journal of Medicine, identifies a functional link between mutation of an immune-system receptor called toll-like receptor 3 (TLR3) and the "dry" type of AMD known as geographic atrophy. The untreatable, progressive disease affects an estimated 8 million Americans, causing permanent vision loss.

The discovery of the first gene associated specifically with dry AMD opens the door to developing treatments, said Dr. Jayakrishna Ambati, a retinal surgeon-scientist in UK's Department of Ophthalmology and Visual Sciences, who along with Dr. Kang Zhang, a retinal specialist and human genetics pioneer at the University of California San Diego, and Nicholas Katsanis, a molecular geneticist at The Johns Hopkins University School of Medicine, led the multi-institutional collaborative study.

Ambati's lab first discovered a relationship between a dysfunctional TLR3 mutation and decreased ocular cell toxicity in a study published in Nature earlier this year. The current study reports that TLR3 activation leads to death of specific cells in the retina and that people with the normal TLR3 gene are two to five times more likely to develop geographic atrophy than those who carry an inactive TLR3 gene mutation.

Ambati’s group plans to start clinical trials next year in patients at risk for developing geographic atrophy using new TLR3 inhibitors developed in his lab.

“We finally have a potential therapy for preventing vision loss from dry AMD," Ambati said. "I am very excited by this discovery."

The study may have major preventive and therapeutic implications, according to Hemin Chin, director of the ocular genetics program at the National Eye Institute.

"Given its high prevalence in the United States and the world, finding effective prevention and treatment strategies for AMD is of critical importance," Chin said. "This finding represents a major advancement in our understanding of dry AMD, for which effective treatment is not yet available."

Of more immediate significance, an investigational drug modality known as short interfering RNA (siRNA) – currently in advanced phase trials for the "wet" type of AMD – also activates TLR3, as shown by Ambati’s earlier Nature study and recently confirmed by another laboratory in the journal Nature Structural & Molecular Biology. The New England Journal of Medicine study raises the possibility that siRNA-based therapies could cause geographic atrophy.

“Collectively, these studies highlight the importance of critically assessing the potential risk posed to patients by siRNA-based therapies,” Ambati said.

Dr. Mark Kleinman and Dr. Wongil Cho, postdoctoral scholars in Ambati's lab, performed the functional studies linking TLR3 and dry AMD in human cells and animal models. Ambati’s laboratory is supported by the NIH National Eye Institute, Burroughs Wellcome Fund, Research to Prevent Blindness, American Health Assistance Foundation, Macula Vision Research Foundation, and Dr. E. Vernon & Eloise C. Smith Endowed Chair. The Foundation Fighting Blindness, Macula Vision Research Foundation, Veterans Affairs Administration; and Ruth and Milton Steinbach Fund also funded this study.

Scientists from University of Utah School of Medicine, Johns Hopkins University, Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital in Chengdu, China, Oregon Health & Science University, University of California San Diego, Greater Baltimore Medical Center, Keck School of Medicine of the University of Southern California and Rockefeller University were part of this joint effort as well.

We "see blue" at the University of Kentucky. We're home not only to powerhouse basketball and the best of intercollegiate athletics; we're also nationally ranked in more than 70 academic programs. We're charting an aggressive, exciting path toward becoming a Top 20 public research institution. “see blue.” is a lot of things, but most of all it's about helping students realize their potential and harness the power of their dreams.

For more about UK’s efforts to become a Top 20 university and how we "see blue," visit www.uky.edu/OPBPA/business_plan.htm

Ann Blackford | Newswise Science News
Further information:
http://www.uky.edu

More articles from Life Sciences:

nachricht Colorectal cancer risk factors decrypted
13.07.2018 | Max-Planck-Institut für Stoffwechselforschung

nachricht Algae Have Land Genes
13.07.2018 | Julius-Maximilians-Universität Würzburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>