Background: MicroRNAs are small, single-stranded, non-protein-coding RNAs of about 22 nucleotides. MicroRNA molecules have been identified to play key roles in a broad range of physiologic and pathologic processes. Polymorphisms in the corresponding sequence space are likely to make a significant contribution to phenotypic variation. A T/C genetic variant (rs11614913) in the pre-miR-196a2 sequence could alter mature miR-196a expression and target mRNA binding. The aim of the present study is to evaluate the relationship between this polymorphism and atrial fibrillation (AF).
Methods: A total of 123 participants were enrolled, 65 AF patients were confirmed with electrocardiogram (ECG) or dynamic electrocardiography, 58 normal individuals were assigned to the control group. Genotypes of the premiR-196a2 were distinguished using the method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.
Results: The distribution of the pre-miR-196a2 genotypes (TT, TC, and CC) was 15.38%, 46.15%, and 38.46% in the AF group and 39.66%, 46.55%, and 13.79% in the controls, respectively (p = 0.0011). Compared with the TT genotype, the C allele carriers (TC+CC genotypes) had a 3.968-fold increased risk of AF (adjusted OR = 3.968, 95% CI = 1.633 - 9.644, p = 0.002). AF patients with the TC+CC genotype had greater left atrial dimension than did patients with the TT genotype (42.10 ± 8.74 vs. 35.13 ± 8.16, p = 0.0224).
Conclusions: Our data support that the pre-miR-196a2 polymorphism is associated with AF, and the C allele is a risk factor for AF.