ROCHESTER, Minn., July 20 (UPI) -- A gene mutation that causes atrial fibrillation by disrupting the potassium ion channels in the heart muscle has been identified.
A team of researchers from the Mayo Clinic found the mutation, called KCNA5. The genetic anomaly was discovered in a sibling pair, both of which suffered from atrial fibrillation but had no known risk factors for the disease.
KCNA5 produces a protein called Kv1.5 that regulates potassium ion metabolism in the cells of the atrial (upper) pumping chambers of the heart. The mutation prevents potassium ions from moving freely across cell membranes, which causes the chaotic, non-rhythmic electrical activation of the atrium known as atrial fibrillation.
Researchers Timothy Olson and Andre Terzic directed the study, the findings of which are published in the July 15 issue of Human Molecular Genetics. Terzic said the research provides a critical step towards the individualized diagnosis and treatment of atrial arrhythmias, and underscored the significance of heredity in this disorder.
According to the authors, atrial fibrillation is the most common cardiac arrhythmia worldwide, and patients with the condition have a fivefold increase in the risk for stroke.
