Association Study of Non-Coding RNA miR-499 and miR196a2 Gene Polymorphisms with the Risk of Idiopathic Recurrent Pregnancy Loss

Background: MicroRNAs (miRNAs) play significant roles in several physiological procedures such as embryo implantation. Recently, findings have indicated that aberrant miRNAs gene expression and single nucleotide polymorphism in the gene encoded miRNAs may be contributed to the pathogenesis of recurrent pregnancy loss (RPL). This investigation aimed to examine potential associations between the two precursor miRNA SNPs miR-196a2 T > C and miR-499 A > G and susceptibility to RPL. Methods: We were analyzing a total of 200 subjects, which consisted of 100 women who experienced three or more recurrent miscarriages and 100 healthy women with one child and without historical aberrations. The genotypic frequencies of two SNPs were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique to assess the association between the presence miRNA gene variant with the risk of RPL. Results: The genotypes frequency of miR-499 gene polymorphism AA/AG + GG and GG/AG + AA showed a statistically significant association with the risk of RPL (P = 0.019; OR= 2.003; 95% CI, 1.116 - 3.594) and (P = 0.024; OR= 2.100; 95% CI, 1.095 - 4.025), respectively. The genotypes frequency of miR-196a2 gene polymorphisms did not reveal a statistically significant difference across the two groups (P > 0.05). Conclusions: Our findings proposed that nucleotide changes in miR-499 gene encoding region may be contributed as a genetic predisposition factor to RPL, whereas the miR-196a2 gene variation cannot be a negative effect on pregnancy outcome.