Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

OHSU researcher finds genetic explanations for some previously unexplained sudden cardiac deaths

07.05.2004


Further research will explore extent of genes’ role in sudden cardiac death



Imagine walking down the street, collapsing without warning and dying within minutes. According to the American Heart Association, about 250,000 Americans suffer sudden cardiac death each year, and half of them may have no prior warning. And, in 5 to 10 percent of all cases, these sudden cardiac deaths remain unexplained since the heart may have no visible abnormality.

In an effort to explore if defects in genes cause these mysterious deaths, Oregon Health & Science University heart researchers studied five genes already known to increase a person’s risk for sudden cardiac death. They found gene defects were responsible, but only in a minority of patients. Further research will be required to determine whether gene defects may also have caused the remaining sudden cardiac deaths. The study, "Postmortem Molecular Screening in Unexplained Sudden Death," was published in the May 5 issue of the Journal of the American College of Cardiology.


"Sudden cardiac death is a big problem. Each time we chip away at one possible solution we get closer to the finding the answer to this complex question," said Sumeet Chugh, M.D., associate professor of medicine (cardiology) in the OHSU School of Medicine, OHSU Heart Research Center scientist and director of OHSU’s Heart Rhythm Research Laboratory. "This is a story that is only just unfolding. This study confirms that our pursuit of genes involved in sudden cardiac death is still in its infancy."

Sudden death is generally defined as a death that occurs within one hour of the patient having symptoms, such as chest pain or difficult breathing. In the majority of people, this condition occurs due to an abnormality of the heart rhythm, known as arrhythmia.

For the first time, Chugh’s team looked at 12 patients who died suddenly but had structurally normal hearts. They looked for mutations in five genes that are already linked to two diseases in the heart’s electrical systems known to cause sudden death, the long QT and Brugada syndromes.

The patients with unexplained sudden cardiac death came from among 270 cases of sudden death that occurred between 1984 and 1996. The work was done in collaboration with the Jesse E. Edwards Registry of Cardiovascular Disease in St. Paul, Minn., that has more than 15,000 archived hearts. Chugh’s team has been working on the project since 1996, and an earlier analysis was published four years ago in the journal Circulation.

Genetic analysis for the present study was performed on DNA prepared from heart muscle tissue stored after being embedded in blocks of wax. Chugh’s team used genetic analysis and cellular tests to determine if any of the five genes were linked to theses deaths. In these young and otherwise healthy individuals with apparently normal hearts, there would be a high likelihood of finding a genetic cause. Of the 12 subjects, however, only two, a 32-year-old female and a 37-year-old male, were found to have a mutation in the gene KCNH2 (HERG). The other four genes, KCNQ1 (KVLQT1), SCN5A, KCNE1 and KCNE2 did not have mutations in these patients with normal hearts.

"Chugh’s discovery takes one giant step toward predicting who is vulnerable for dying suddenly and it brings hope that we may some day prevent the form of cardiac death that comes without warning," said Kent Thornburg, Ph.D., director of the OHSU Heart Research Center and professor of medicine (cardiology) in the OHSU School of Medicine.

Since February 2002 Chugh has worked with a team of researchers and community agencies to collect information on every sudden unexplained death in Multnomah County, Oregon. The Oregon Sudden Unexplained Death Study (Ore-SUDS) will be the first genome bank and data base to provide researchers with more comprehensive data about the deceased patient’s heart at the time of death. Chugh said the current five-gene study confirms the need for this more extensive registry. More information about Ore-SUDS can be found at www.oregonsuds.org.

"For this lethal condition in which half of the people die without prior notice or warning, our quest is to predict the risk of sudden cardiac death before it happens," said Chugh.

Sudden cardiac death is a significant health threat in Oregon. The Centers for Disease Control and Prevention, which is funding Ore-SUDS, reports that more than 70 percent of cardiac deaths in Oregon are sudden, one of the highest percentages in the country. The overwhelming majority of these patients have associated coronary heart disease.

Funding for this work was provided by the American Heart Association, the Doris Duke Charitable Foundation, CDC and the National Institutes of Health.

The other study authors are: Olga Senashova, Division of Cardiology, OHSU School of Medicine; Allison Watts, Division of Cardiology, OHSU School of Medicine; Phuoc Tran, Ph.D., Department of Molecular and Medical Genetics, OHSU School of Medicine; Zhengfeng Zhou, M.D., Ph.D., Division of Molecular Medicine, OHSU School of Medicine; Qiuming Gong, M.D., Ph.D., Division of Molecular Medicine, OHSU School of Medicine; Jack Titus, M.D., Ph.D., Jesse E. Edwards Registry of Cardiovascular Disease, St. Paul, Minn.; and Susan Hayflick, M.D., Department of Molecular and Medical Genetics, OHSU School of Medicine.

Christine Pashley | OHSU
Further information:
http://www.ohsu.edu/news/2004/050504suds.html

More articles from Health and Medicine:

nachricht Penn studies find promise for innovations in liquid biopsies
30.03.2017 | University of Pennsylvania School of Medicine

nachricht 'On-off switch' brings researchers a step closer to potential HIV vaccine
30.03.2017 | University of Nebraska-Lincoln

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: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

NASA laser communications to provide Orion faster connections

30.03.2017 | Physics and Astronomy

Reusable carbon nanotubes could be the water filter of the future, says RIT study

30.03.2017 | Studies and Analyses

Unique genome architectures after fertilisation in single-cell embryos

30.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>