WASHINGTON Two genetic mutations have been identified that increase the risk of a common heart rhythm problem linked to stroke, according to researchers who have developed a test to identify people who have them.
Writing on Sunday in the journal Nature, scientists scanned the genes of thousands of people from Iceland, Sweden, the United States and Hong Kong to find these two common mutations tied to much higher risk for atrial fibrillation.
This condition is a heart rhythm problem that can cause heart palpitations, shortness of breath, fatigue and stroke.
The two mutations are located adjacent to a gene that plays a role in early heart development, the researchers found.
Scientists from Icelandic company deCODE genetics Inc. led the research.
The company also launched a laboratory test for the two mutations in order to help doctors identify people who might be at high risk for atrial fibrillation and, thus, stroke.
"Why is it important to identify those who are at risk for this kind of a problem? The reason for that is that atrial fibrillation predisposes for stroke. And stroke is a common cause of disability in our society," deCODE genetics President and Chief Executive Officer Dr. Kari Stefansson said in a telephone interview.
Atrial fibrillation is a condition in which the heart's two upper chambers beat chaotically and irregularly, out of coordination with its two lower chambers. The result is an irregular and frequently rapid heart rate.
It can increases one's risk of developing blood clots that may trigger a stroke. A stroke occurs when blood flow to the brain stops, causing brain cells to begin dying in minutes.
Researchers around the world have been intensively scouring the human genome to find genetic links to various diseases in the hope of developing new ways to prevent or treat them.
In another study published on Sunday in the journal Nature Genetics, deCODE genetics identified two genetic factors on human chromosome 17 linked to an increased likelihood of developing prostate cancer.
These are believed to play a role in more than a third of prostate cancer cases, the researchers said.
But while raising prostate cancer risk, the researchers added, one of these genetic factors actually lowered the risk of the most common form of diabetes, known as type 2 diabetes.
"It only shows how delicate the biology of man is and how important it is when you are considering treatment or prevention of one disease to make sure that you are not increasing, then, the liability for another one," Stefansson said.