Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Genome-wide association studies mislead on cardiac arrhythmia risk gene

21.03.2014

Although genome-wide association studies have linked DNA variants in the gene SCN10A with increased risk for cardiac arrhythmia, efforts to determine the gene's direct influence on the heart's electrical activity have been unproductive.

Now, scientists from the University of Chicago have discovered that these SCN10A variants regulate the function of a different gene, SCN5A, which appears to be the primary gene responsible for cardiac arrhythmia risk. The SCN10A gene itself plays only a minimal role in the heart, according to the study, published in the Journal of Clinical Investigation on March 18.

"Significant effort has been invested into understanding the function of SCN10A in cardiac rhythm control, with underwhelming results," said study co-leader Ivan Moskowitz MD, PhD, associate professor of pediatrics, pathology and human genetics at the University of Chicago. "It turns out that the genetic variation within SCN10A that confers arrhythmia risk actually functions on a different gene. This study highlights the fact that DNA variation associated with disease can have regulatory impact on functional targets located a considerable distance away."

Mutations within the SCN10A gene are linked with increased risk of Brugada Syndrome, which causes cardiac arrhythmias and is a leading cause of death amongst youth in some parts of the world. Genome-wide association studies—large scale experiments that look for genetic variants across the human genome with statistical associations to certain traits or diseases—were used to identify these variants, but follow-up studies have been unable to determine their function.

Curious about previous ambiguous results, Moskowitz and his colleagues looked for other genes with links to SCN10A. First, they discovered that the region of SCN10A that conferred arrhythmia risk physically contacted a neighboring gene—SCN5A—which is well-known to have an important role in cardiac arrhythmias and sudden cardiac death. They then showed that these contacts are functional, and that by removing the implicated sequences from SCN10A, expression of SCN5A was profoundly diminished.

When they analyzed large-scale human data, the team found that the SCN10A variant originally identified for Brugada Syndrome risk was associated with lowered levels of SCN5A. But the variant had no detectable effect on the levels of SCN10A.

Taken together, the evidence suggests that any link between SCN10A and cardiac arrhythmia is due to its connection with SCN5A expression. Through the results of this study, Moskowitz believes scientists will now focus on the correct gene, SCN5A, to better understand genetic risk for cardiac arrhythmia and hopes this will lead to more accurate diagnostics and potential therapies in the future.

This study also illustrates how highly-publicized genome-wide association studies can be misleading for researchers. Study co-leader Marcelo Nobrega, PhD, an associate professor of human genetics at the University of Chicago, published a similar finding for a gene associated with obesity, on March 12th in Nature.

"Genome-wide association studies have been very successful in implicating genetic variation associated with a host of human diseases and traits," Moskowitz said. "However cases like this study demonstrate that we must be more careful to evaluate the functional target of genome-wide association study hits, before we jump to conclusions that can have costly implications for how we investigate human health and generate disease diagnostics and therapies."

###

The study, "A common genetic variant within SCN10A modulates cardiac SCN5A expression," was funded by the National Institutes of Health, the European Community's Seventh Framework Programme contract, the Cardiovascular Onderzoek Nederland, the German Foundation for Heart Research and the Federal Ministry of Education and Research. Additional authors include Malou van den Boogaard, Scott Smemo, Ozanna Burnicka-Turek, David E. Arnolds, Harmen J.G. van de Werken, Petra Klous, David McKean, Jochen D. Muehlschlegel, Julia Moosmann, Okan Toka, Xinan H. Yang, Tamara T. Koopmann, Michiel E. Adriaens, Connie R. Bezzina, Wouter de Laat, Christine Seidman, J.G. Seidman, Vincent M. Christoffels and Phil Barnett.

Kevin Jiang | EurekAlert!
Further information:
http://www.uchospitals.edu

Further reports about: Medical SCN10A arrhythmias cardiac function genome-wide levels variant

More articles from Life Sciences:

nachricht New Technique Maps Elusive Chemical Markers on Proteins
03.07.2015 | Salk Institute for Biological Studies

nachricht New approach to targeted cancer therapy
03.07.2015 | CECAD - Cluster of Excellence at the University of Cologne

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Viaducts with wind turbines, the new renewable energy source

Wind turbines could be installed under some of the biggest bridges on the road network to produce electricity. So it is confirmed by calculations carried out by a European researchers team, that have taken a viaduct in the Canary Islands as a reference. This concept could be applied in heavily built-up territories or natural areas with new constructions limitations.

The Juncal Viaduct, in Gran Canaria, has served as a reference for Spanish and British researchers to verify that the wind blowing between the pillars on this...

Im Focus: X-rays and electrons join forces to map catalytic reactions in real-time

New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions

A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...

Im Focus: Iron: A biological element?

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...

Im Focus: Thousands of Droplets for Diagnostics

Researchers develop new method enabling DNA molecules to be counted in just 30 minutes

A team of scientists including PhD student Friedrich Schuler from the Laboratory of MEMS Applications at the Department of Microsystems Engineering (IMTEK) of...

Im Focus: Bionic eye clinical trial results show long-term safety, efficacy vision-restoring implant

Patients using Argus II experienced significant improvement in visual function and quality of life

The three-year clinical trial results of the retinal implant popularly known as the "bionic eye," have proven the long-term efficacy, safety and reliability of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

World Conference on Regenerative Medicine: Abstract Submission has been extended to 24 June

16.06.2015 | Event News

MUSE hosting Europe’s largest science communication conference

11.06.2015 | Event News

 
Latest News

Siemens receives order for offshore wind power plant in Great Britain

03.07.2015 | Press release

'Déjà vu all over again:' Research shows 'mulch fungus' causes turfgrass disease

03.07.2015 | Agricultural and Forestry Science

Discovery points to a new path toward a universal flu vaccine

03.07.2015 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>