Gene variant that causes fatal heart rhythm disorder identified
Washington, Oct 8 : Researchers at the University of Iowa and colleagues in France
have identified a gene variant that causes a potentially fatal human heart rhythm disorder
called sinus node disease or 'sick sinus syndrome.'
While the newly discovered gene variant is rare, the study sheds light on cellular
mechanisms that regulate sinus node function and identifies an unanticipated new pathway
for developing future therapies to regulate more common forms of sinus node disease.
For the study, the researchers analyzed data from two families in France: a family of
74 individuals, 26 of whom had sinus node dysfunction, and a family of 44 individuals, 13
of whom had the disease.
Many of the affected individuals carried the same gene variant, and many experienced
variable heart rate and bradycardia (dangerously low heart rate).
The researchers found that variants in a gene called ankyrin 2, or ANK2, resulted in
dysfunction in the protein ankyrin-B in the members of these two different families.
"While a small number of the patients displayed heart disease symptoms, including
ventricular arrhythmias, the prevalence of sinus node dysfunction in these patients was
extremely high. In fact, most required the implantation of cardiac pacemakers," said the
study's senior author Peter Mohler, Ph.D., associate professor of internal medicine in the
University of Iowa Carver College of Medicine.
"We predict that there are likely additional unidentified ankyrin variants in the
larger general population that predispose humans to a combination of heart disease
symptoms, including sinus node dysfunction, atrial fibrillation and ventricular
arrhythmias," he added.
The findings were published online Oct. 1 by the Proceedings of the National Academy of
Sciences.
--ANI
