Featured Research

from universities, journals, and other organizations

Gene Identified For Heart Defect That Causes Sudden Death In Young People

Date:
December 22, 1998
Source:
American Heart Association
Summary:
A gene for an inherited heart disorder that accounts for a significant number of sudden deaths and heart failure in young people has been located -- or mapped -- by U.S. and Canadian researchers, who report their research in today's Circulation: Journal of the American Heart Association. The gene, found on chromosome 3, is responsible for a heart condition called arrhythmogenic right ventricular dysplasia (ARVD).

DALLAS, Dec. 22 -- A gene for an inherited heart disorder that accounts for a significant number of sudden deaths and heart failure in young people has been located -- or mapped -- by U.S. and Canadian researchers, who report their research in today's Circulation: Journal of the American Heart Association. The gene, found on chromosome 3, is responsible for a heart condition called arrhythmogenic right ventricular dysplasia (ARVD), says the study's lead author, Robert Roberts, M.D., professor of medicine and cell biology at Baylor College of Medicine in Houston.

Related Articles


"It should be possible to isolate and clone -- or reproduce -- the gene and identify the mutation within two years," says Roberts. Cloning the ARVD gene should help scientists better understand this puzzling heart disorder, Roberts says. It should also offer important insights into broader questions regarding sudden-death heart attacks -- in which death occurs within hours -- and heart failure, a severe weakening of the heart's ability to pump blood.

Roberts and his colleagues located the ARVD gene by studying the genetic family tree of a North American family through seven generations. They had information on more than 200 members of the family, including 10 who were living and diagnosed with ARVD. They obtained blood samples from 149 family members of the 10 living individuals and linked the mutant gene that causes ARVD in the family to chromosome 3.

ARVD strikes about 1 in 5,000 people and accounts for about 15 percent of sudden deaths in young people, say researchers. It is an autosomal dominant disease, which means a person needs to inherit a defective gene from only one parent to develop the disorder. Children and young adults with ARVD have a 2.5 percent chance of dying in any year.

The disease is difficult to diagnose. Often, the first symptom of ARVD is death, triggered by erratic heartbeats called arrhythmias. Those who do not suffer sudden death develop symptoms of heart failure -- including swelling of the hands and feet and shortness of breath -- in their 30s and 40s, and usually die within a few years.

In ARVD, the heart muscle in the right ventricle, the side of the heart that pumps blood to the lungs, dies and is replaced by fat cells and fibrous tissue. The muscle cells die because of an unknown defect in the body's natural system of programmed cell death, called apoptosis, in which the body rids itself of malfunctioning cells.

"This is an unusual disease because the muscle cells of the ventricle actually die," he adds. "The problem here is a defect in one of the mechanisms of apoptosis, which is the subject of major research all over the western world right now. If we can find the mechanism of this defect, it would help unlock the process of programmed cell death."

Now the race is on to clone the gene and devise a simple test that will tell family members of individuals with ARVD whether they too have inherited this specific faulty gene. Some members of the tested family already have had automated defibrillators implanted in their bodies to try to protect themselves against sudden bursts of fatal arrhythmias.

The ARVD gene lies on a stretch of 7 million base pairs of DNA (the chemical component of the gene), which comprise perhaps 150 genes. Of these genes, only a few are likely to be active in the heart. The researchers will first determine which genes are expressed in the heart and then examine these genes for a single gene mutation that is shared by family members who have ARVD. "Once we find a mutation, then we can just take a blood sample and make the diagnosis," says Roberts. "The technology is moving so fast in genetics that if we get any luck at all we could have it cloned within a year. We are certainly putting a lot of effort into it.

"By finding the cause of an inherited disease we can design targeted therapies and understand similar diseases that cause sudden death and heart failure," Roberts says.

He cites as an example the unraveling of the genetics of familial hypercholesterolemia, a rare inherited form of heart disease that is characterized by high blood levels of cholesterol in young people. This finding helped to define the role of cholesterol metabolism in heart attacks. Scientists are intrigued by the fact that ARVD occurs only in the right ventricle. Two other inherited heart disorders that can cause sudden and early death occur only in the larger left ventricle, which pumps blood to the rest of the body. This ventricle-specific occurrence mystifies researchers.

"As far as we know, the same genes are found in the right ventricle as the left ventricle," Roberts says. "The gene may not be present in one of the ventricles, but this is unlikely. The most likely reason is that the gene's interaction with the right ventricle is different than if it were in the left. If we can find the gene, we should be able to confirm this."

Co-authors of the paper are Ferhaan Ahmad, M.D.; Duanxiang Li, M.D.; Akihiko Karibe, M.D., Ph.D.; Oscar Gonzalez, B.S.; Terry Tapscott, B.S.; Rita Hill, B.S.N.; Donald Weibaecher, M.D.; Peter Blackie, M.D.; Michael Furey, M.D.; Martin Gardner, M.D.; and Linda L. Bachinski, Ph.D.


Story Source:

The above story is based on materials provided by American Heart Association. Note: Materials may be edited for content and length.


Cite This Page:

American Heart Association. "Gene Identified For Heart Defect That Causes Sudden Death In Young People." ScienceDaily. ScienceDaily, 22 December 1998. <www.sciencedaily.com/releases/1998/12/981222081109.htm>.
American Heart Association. (1998, December 22). Gene Identified For Heart Defect That Causes Sudden Death In Young People. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/1998/12/981222081109.htm
American Heart Association. "Gene Identified For Heart Defect That Causes Sudden Death In Young People." ScienceDaily. www.sciencedaily.com/releases/1998/12/981222081109.htm (accessed October 31, 2014).

Share This



More Health & Medicine News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Melafind: Spotting Melanoma Without a Biopsy

Melafind: Spotting Melanoma Without a Biopsy

Ivanhoe (Oct. 31, 2014) The MelaFind device is a pain-free way to check suspicious moles for melanoma, without the need for a biopsy. Video provided by Ivanhoe
Powered by NewsLook.com
Battling Multiple Myeloma

Battling Multiple Myeloma

Ivanhoe (Oct. 31, 2014) The answer isn’t always found in new drugs – repurposing an ‘old’ drug that could mean better multiple myeloma treatment, and hope. Video provided by Ivanhoe
Powered by NewsLook.com
Chronic Inflammation and Prostate Cancer

Chronic Inflammation and Prostate Cancer

Ivanhoe (Oct. 31, 2014) New information that is linking chronic inflammation in the prostate and prostate cancer, which may help doctors and patients prevent cancer in the future. Video provided by Ivanhoe
Powered by NewsLook.com
Sickle Cell: Stopping Kids’ Silent Strokes

Sickle Cell: Stopping Kids’ Silent Strokes

Ivanhoe (Oct. 31, 2014) Blood transfusions are proving crucial to young sickle cell patients by helping prevent strokes, even when there is no outward sign of brain injury. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins