CTLA-4 and IL-6 gene polymorphisms: Risk factors for recurrent pregnancy loss

The purpose of the present study was to evaluate the possible association between CTLA-4 +49A/G and IL-6 -634C/G polymorphisms, and the risk of recurrent pregnancy loss (RPL). 240 women (120 healthy controls and 120 with RPL) were enrolled in this case-control study. Genotyping was performed using a PCR-RFLP technique. In the case of polymorphic CTLA-4 +49A/G, the wild type allele G was associated with a decreased risk of RPL (OR: 0.42, 95%CI: 0.25-0.69, p=0.001). As to IL-6 -634C/G polymorphism, a highly significant difference was observed, and those women who carry at least one mutant G allele presented a probability of developing RPL about 5 times greater than controls (OR: 5.1, 95%CI: 1.04-25.3, p=0.04). The results indicate that polymorphisms of CTLA-4 and IL-6 genes may influence the risk of developing RPL among Iranian women, suggesting that more research on the immunogenetics of pregnancy should be conducted to confirm our results, and to declare the exact roles of studied molecules in RPL pathogenesis.