Genetic Regulation Linked to Heart Arrhythmia

Gene found to cause irregular heart beat

(RxWiki News) An irregular heart beat could be caused by a wide range of factors -- from scarring after a heart attack to diabetes and high blood pressure. New research also suggests a genetic link.

Gladstone Institutes scientists have discovered the identity of a genetic regulator that is capable of causing the heart to beat out of sync. Discovery of the regulator that uses electrical impulses to synchronize the heart beat can lead to better understanding of heart arrhythmias and could prompt new treatments -- possibly even a cure one day.

"Talk to your cardiologist about the best arrhythmia treatments."

Dr. Deepak Srivastava, director of cardiovascular research at the California-based Gladstone Institutes, said the finding marks important progress for better understanding arrhythmias, which can be fatal when combined with heart failure. He said this study is the first about a genetic regulator that coordinates the timing of the electrical impulses that make the heart beat correctly.

In order for the heart to efficiently pump blood to the rest of the body, electrical impulses must spread rapidly and in a coordinated manner along a network of heart cells. Scientists found that genetic regulator Irx3 is responsible for coordinating these impulses.

Researchers switched off the Irx3 gene in mice and found that the heart's pumping fell out of sync. The electrical impulses slowed and struggled to reach their intended destinations. As a result the mice developed arrhythmias because the heart's chambers lost the ability to beat in the correct time.

Dr. Benoit G. Bruneau, a Gladstone investigator and professor of pediatrics at the University of California San Francisco, which is affiliated with Gladstone, said the findings could help prevent and treat human heart disease once the role of the newly discovered gene is better understood. He said investigators plan to examine whether humans with arrhythmias have mutations in the Irx3 gene.

Dr. Bruneau also plans to attempt drug therapy to target electrical impulse pathways that the gene regulates. Though treatments could be off in the distance, the finding could eventually lead to ways to stop heart arrhythmias in patients.

The research has been published in the early edition of the Proceedings of the National Academy of Sciences.

Review Date: 
August 8, 2011