Association of microRNA-146a rs57095329 Polymorphism with Susceptibility to Primary Gout in a Chinese Han Population

MicroRNA-146a (miR-146a) plays a critical role in the regulation of autoinflammatory diseases, including gout. There is growing evidence that miR-146a gene single nucleotide polymorphisms (SNPs) are associated with different diseases, but no genetic relevance studies of miR-146a gene polymorphisms to gout have been reported by now.The purpose of this study was to examine the relationship between the miR-146a rs57095329 genetic polymorphism and the susceptibility to primary gout in the Chinese Han population.A case-control study was performed in this report to examine the potential association between gout and the functional rs57095329 SNP of miR-146a in a Chinese population consisting of 448 primary gout patients (containing 76 tophi patients) and 418 healthy controls. MiR-146a expression in peripheral blood mononuclear cells (PBMCs) was measured in 81 gout patients (including 32 tophi patients and 49 non-tophi patients) and 47 healthy subjects.There was no significant difference found in the distribution of miR-146a rs57095329 between 448 gout patients and 418 healthy subjects (P > 0.05). However, significant differences in genotypes and allele distributions were found between 76 gout with tophi patients and 418 healthy subjects, as well as between gout with tophi (76) and with no tophi patients (372) (P < 0.01, respectively). Gout patients with AG/GG genotypes had a 0.323-fold reduced risk for tophi than those with the AA genotype, and the G allele had a 0.362-fold reduced risk of tophi. Furthermore, in 32 tophi patients, the GG genotype was significantly associated with increased expression of miR- 146a.Our findings suggest that rs57095329 may play a protective role in tophi gout susceptibility, and rs57095329 A > G variant may modulate the expression of miR-146a in tophi patients.