SNPs confer 70% and 40% increased risk of disease.
Investigators at deCODE genetics, in collaboration with academic colleagues in Iceland, the U.S., Sweden, and China, discovered that two common SNPs in the genome confer a risk of atrial fibrillation (AF).
The variants, located on chromosome 4q25, create an approximately 70% and 40% increase above average risk of AF, per copy carried. Results also show that those who carry two copies of the more powerful variant are at a more than 250% greater likelihood of AF than those who carry neither variant. About one third of people with European ancestry carry at least one copy of one of the risk variants. The gene nearest to these SNPs, PITX2, is known to play an important role in the development of the heart.
deCODE discovered the variants, the T alleles of SNPs rs2200733 and rs10033464, through analysis of more than 300,000 SNPs in a total of more than 5,000 Icelanders with AF and/or atrial flutter as well as healthy control subjects. These findings were subsequently replicated in case-control cohorts from Iceland, the Massachusetts General Hospital in Boston, and the Karolinska Institute in Stockholm, including a total of 18,000 subjects. The stronger variant was also confirmed in a Han Chinese population from Hong Kong.
The article is published in the online edition of Nature.