Atrial Fibrillation’s Genetic Cause Uncovered

by: AFAnswers.com staff

In a recent study published in the Human Molecular Genetics journal, researchers at the Mayo Clinic in Rochester, Minn., announced the discovery of the genetic cause or predisposition for Atrial Fibrillation (AF).7

The source is a gene mutation, which causes chaotic electrical activation of the heart muscle. When comparing genes of pairs of siblings with no known risk factors for the disease, the researchers found the mutation existed only in the genes of those currently diagnosed with AF.

The Mayo researchers were the first to identify a genetic mutation in the gene KCNA5 that leads to a condition called channelopathy — a condition which may cause other diseases. A channelopathy is a dysfunction involving the ion channels in a cell membrane — the small transportation tubes responsible for transporting ions, such as potassium, sodium and calcium. The job of these tubes is to regulate the passage of ions, or charged particles, in and out of the cell and in turn, regulate the heartbeat. The mutation observed by researchers causes a loss of function of an atrial-specific potassium ion channel and disturbs the electrical currents within the heart.

This particular mutation was observed in the KCNA5 gene — a gene that produces a key heart protein known as Kv1.5. Without the production of this protein, the heart muscle or more specifically, the atria, become more susceptible to AF, as well as other stress-induced arrhythmias.

While the discovery of this information isn’t an immediate cure for AF or other arrhythmias, it is a critical step toward an individual diagnosis and treatment of arrhythmia patients.

Published: January 1, 2007