A Sequence Variant On Chromosome 4q25 Is Associated With Atrial Fibrillation

Approximately 10 million Chinese people are affected by atrial fibrillation (AF). AF is an independent risk factor for stroke, but its genetic basis is largely unknown. A recent genome-wide association study in Iceland identified association between a single nucleotide polymorphism (SNP) rs2200733 on chromosome 4q25 and AF, mainly in Caucasian populations. However, the association between rs2200733 and AF in the Chinese population needs to be further studied. We enrolled 383 AF patients and 851 controls (a GeneID cohort) in this study to assess the association between rs2200733 with AF in a mainland Chinese Han population. A case-control association study was carried out. The SNP was genotyped in our GeneID cohort, and the genotyping data were analyzed using Pearson's 2×2 and 2×3 contingency tableχ² test. Odds ratios (ORs) were estimated using theχ² test. Highly significant allelic association was detected between rs2200733 and AF in the Chinese Han population with a p-value of 3.7×10^-11 (OR=1.81). Analysis for genotypic association suggested that rs2200733 probably confers susceptibility to AF in a dominant model. The association remained significant after adjusting for risk factors for AF. In conclusion, SNP rs2200733 confers a significant risk of AF in the mainland Chinese Han population, which expands the association between rs2200733 and AF to a representative mainland Chinese Han population. These results indicate that there exists an important AF gene on chromosome 4q25, and future studies should focus on identification of the specific disease-causing gene at the locus.