Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gene discovery may shed light on kidney disease

02.08.2006
Second gene found for Alagille syndrome may have broader role

In a finding that may have broader implications for understanding kidney disorders, genetics researchers at The Children's Hospital of Philadelphia have identified a second gene that gives rise to Alagille syndrome, a genetic developmental disease that affects multiple organs. The Children's Hospital team previously discovered the first gene associated with this disease.

The researchers found that mutations in the NOTCH2 gene were linked to kidney abnormalities in patients and families. "While Alagille syndrome is relatively rare, organ diseases are not rare, and our findings suggest that genes on this biological pathway may have a broader role in kidney disorders," said study leader Nancy B. Spinner, Ph.D., a geneticist at The Children's Hospital of Philadelphia.

The study appears in the July issue of the American Journal of Human Genetics.

Dr. Spinner led the Children's Hospital team that identified mutations in the JAG1 gene as a cause of Alagille syndrome in 1997. Like the NOTCH2 gene analyzed in the current study, JAG1 is part of a signaling pathway that governs important processes in early human development.

Alagille syndrome, estimated to occur in one in 20,000 individuals, is a complex disorder, primarily affecting the liver, heart, eyes, face and skeleton. Some patients with Alagille syndrome have very mild symptoms or isolated problems, while others may have severe, life-threatening heart or liver defects.

Both the JAG1 and the NOTCH2 genes participate in the Notch signaling pathway. JAG1 codes for the ligand Jagged1, a signaling protein that triggers receptors in the pathway. The NOTCH2 gene codes for Notch2, which is one of those receptors. The pathway as a whole is active during embryonic development, and transmits signals to cells to develop into specialized organs. Mutations in those genes are thought to disrupt normal development, by, for instance, causing the defective bile ducts found in the livers of many patients with Alagille syndrome.

"Ligands and receptors are like keys and locks," said Dr. Spinner. "If either one is defective, it may interfere with normal growth and development."

Dr. Spinner's team previously determined that 94 percent of patients diagnosed with Alagille syndrome had mutations in the JAG1 gene. In the current study, they analyzed 11 patients with Alagille syndrome who did not have the JAG1 mutation, and found that two of them had mutations in NOTCH2. Furthermore, the patients had three family members, all mildly affected, who also had the same mutation. All five individuals had kidney disease.

Because their study identified only two families with NOTCH2 mutations, said Dr. Spinner, it is not definitive in establishing that those mutations cause a distinct variety of Alagille syndrome. However, it is the first study to report that mutations in the NOTCH2 gene cause human disease. Dr. Spinner is planning further studies to better characterize the role of NOTCH2 mutations and the Notch signaling pathway in the wider population of patients with kidney disorders.

She also will investigate liver involvement in Alagille syndrome under the Rare Diseases Clinical Research Network, recently established by the National Institutes of Health. "Part of the rationale for this research network is that, collectively, relatively rare diseases added together constitute a significant portion of the population," said David A. Piccoli, M.D., chief of Gastroenterology and Nutrition at Children's Hospital and a co-author of the study. "Another rationale is that studying relatively rare diseases may offer insights into more common diseases and into health in general."

John Ascenzi | EurekAlert!
Further information:
http://www.chop.edu

More articles from Life Sciences:

nachricht Topologische Quantenchemie
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

nachricht Topological Quantum Chemistry
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>