Association of MicroRNA-146a expression level and it’s Gene Polymorphism rs2910164 C/G in patients with Rheumatoid Arthritis

¹ Faculty of Medicine, Jabir Ibn Hayyan University for Medical and Pharmaceutical sciences, 54001 Najaf, Iraq
² Faculty of Science, University of Kufa, 29CG+62H Kufa, Iraq
³ Faculty of Medicine, Babylon University, Iraq

^* Corresponding author: athraa.jaleel@jmu.edu.iq

Abstract

MicroRNAs are small non-coding RNAs that can regulate a variety of immune functions. MicroRNA146a (miRNA-146a) is regarded as a crucial regulator of posttranscriptional gene expression, suggesting a role in autoimmune disorders. This study was performed to investigate association miRNAs-146a expression and its polymorphisms in patient with Rheumatoid arthritis. The current study includes 120 subjects classified into two main groups: 60 RA patients and 60 healthy controls. Quantitative expression of serum miRNA-146a, as well as its genotyping rs2910164 (C/G) were done to all subjects using real-time PCR and Tetra primer ARMS-PCR respectively. Serum miRNA-146a significantly over expressed in RA patients (fold change 2.59±1.18), compared to the controls (fold change 1.07±0.41), (P=< 0.0001).The receiver operating characteristics (ROC) curve was plotted to compare the expression efficiency of miR-146a showing high sensitivity 91.7 % and high specificity 91.1 %, AUC 0.95, (95% CI 0.91-0.99), the cut off value was (1.57). On the other hand MiRNA-146a (rs2910164) genotyping revealed that no significant variation between the RA patients in the comparison with the control group under all co-dominant model heterozygous genotype (C/G), co-dominant model homozygous genotype (G/G), dominant pattern (C/G+G/G) genotypes, recessive model (G/G) genotype. Analysis of the allele frequencies no statistically significant differences between patients and controls. Conclusion miRNAs-146a expression can be used as diagnostic markers for RA patients and miRNA-146a rs2910164 C/G not associated with RA susceptibility. The C allele of miRNA-146a (rs2910164) can be considered to be protective.