deCODE isolates biomarker for AF risk

A paper published in the July 1 edition of Nature describes the discovery by scientists at Iceland's deCODE genetics, in collaboration with academic colleagues, of two common single-letter variations in the genome conferring risk of atrial fibrillation, the most common cardiac arrhythmia and the leading cause of cardiogenic stroke.

The variants, both located on chromosome 4q25, confer an approximately 70% and 40% increase above average risk of AF, respectively, per copy carried, deCODE noted. Approximately one third of people of European ancestry carry at least one copy of the risk variants, and deCODE's results show that those who carry two copies of the more powerful variant are at a more than 250% greater likelihood of AF than those with neither variant. The gene nearest to these SNPs, PITX2, is known to play an important role in the development of the heart.

deCODE has launched deCODE AF, a reference laboratory test for the variants. Because AF is the biggest risk factor for cardiogenic stroke, the company believes that testing for these variants will provide doctors with a targeted and cost-effective means of identifying those who should be intensively monitored for the condition. Current best clinical practice recommends that stroke patients with AF can significantly reduce their risk of a second event by taking the anticoagulant drug warfarin.