The effects of tumor necrosis factor-α (TNF-α) and IL-1 receptor antagonist (IL-1Ra) polymorphisms on recurrent abortion in Azari women

Objectives: Recurrent pregnancy loss (RPL) is a heterogeneous condition consisting of three or more consecutive abortions before the 20 weeks of gestation. The tumor necrosis factor alpha (TNF-α) gene plays a crucial role in immunology and inflammation responses. Interleukin 1 receptor antagonist (IL-1RN) is an important anti-inflammatory molecule which plays important roles in pregnancy. The aim of this study was to investigate effects of TNF-α and IL-1Ra polymorphisms on RPL in Azari women. Material and methods: The study participants consisted of 100 women with RPL from Iranian Azeri Turkish origin. The control group comprised 100 age and ethnically matched healthy women in the reproductive age. Genomic DNA was extracted from the whole blood and genotype determinations were performed using PCR amplification followed by restriction fragment length polymorphism (RFLP) analysis. Results: No significant association was indicated between IL-1Ra and RPL among Iranian Azeri Turkish women. Unlike the homozygous state, significantly higher frequency of -857 C/T variant was seen in RPL patients than control subjects. Significantly lower frequency of wild type genotype was observed in RPL patients than of controls. Any association was found between the other TNF-α polymorphisms and RPL. Conclusions: TNF-α -857 C/C variant might represent protective effect against RPL and the -857 C/T variant might be a genetic risk factor for the occurrence of RPL. Invariant differences in the prevalence of -511 C/T and -31 C/T polymorphisms and IL-1RN VNTR between RPL patients.