XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
 Surgery
 Aging
 Ophthalmology
 Gynaecology
 Neurosciences
 Pharmacology
 Cardiology
 Obstetrics
 Infectious Diseases
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
  Dialysis
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
 
 India
Search

Last Updated: Nov 18, 2006 - 12:32:53 PM

Nephrology Channel
subscribe to Nephrology newsletter

Latest Research : Nephrology

   DISCUSS   |   EMAIL   |   PRINT
NOTCH2 gene mutations linked to Alagille syndrome
Aug 1, 2006 - 1:30:00 PM, Reviewed by: Dr. Priya Saxena

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

 
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."
 

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

www.chop.edu

 
Subscribe to Nephrology Newsletter
E-mail Address:

 

The National Institute for Diabetes and Digestive Diseases supported this study, as did the Fred and Suzanne Biesecker Center at The Children's Hospital of Philadelphia. Co-authors with Drs. Spinner and Piccoli, all from Children's Hospital and the University of Pennsylvania School of Medicine, were Ian Krantz, M.D.; Ryan McDaniell, Daniel M. Warthen, Pedro A. Sanchez-Lara and Athma Pai.

About The Children's Hospital of Philadelphia: The Children's Hospital of Philadelphia was founded in 1855 as the nation's first pediatric hospital. Through its long-standing commitment to providing exceptional patient care, training new generations of pediatric healthcare professionals and pioneering major research initiatives, Children's Hospital has fostered many discoveries that have benefited children worldwide. Its pediatric research program is among the largest in the country, ranking second in National Institutes of Health funding. In addition, its unique family-centered care and public service programs have brought the 430-bed hospital recognition as a leading advocate for children and adolescents.


Related Nephrology News

Kidney stones? Have some orange juice!!!
NOTCH2 gene mutations linked to Alagille syndrome
Fetal hydronephrosis mystery solved
Alport Syndrome: From Pathogenesis to a Potential Therapy
Meckel-Gruber syndrome gene identified- a help to understand polycystic kidney disease
Dialysis patients may be overmedicated
Mycophenolate mofetil may be more effective in inducing lupus nephritis remission
Dialysis patients often have close family members also on dialysis - Study
Prognosis Improving For Diabetics With End Stage Renal Disease
Osmolytes critical to survival of kidney cells


For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us