The Study of Association Between Polymorphism of TNF-α Gene’s Promoter Region and Recurrent Pregnancy Loss

Background: According to the literature review, polymorphisms of tumor necrosis factor alpha's (TNF-α) promoter region are probably the genetic risk factors of recurrent pregnancy loss. This study has investigated five single nucleotide polymorphisms in the TNF-α gene's promoter region to evaluate their relationship with recurrent pregnancy loss disorder. Methods: Blood samples were taken from 65 women with recurrent pregnancy loss (Case group) and 65 healthy women with a history of successful pregnancy (Control group). Polymerase chain reaction with high resolution melting (PCR-HRM) analysis was done to determine the promoter region of -308G/A, -850T/C, -238G/A, -1031T/C and -863A/C TNF-α polymorphisms. The data were assessed using logistic regression models. P values less than 0.05 were considered statistically significant. Results: Significant associations were found between recurrent pregnancy loss and -863C/A (p=0.000), -308G/A (p=0.045), and -238G/A (p=0.034) polymorphisms. TNF-α polymorphisms of -863C and -238G may be susceptible factors of recurrent pregnancy loss cases. The -308G polymorphism has an important role in maintaining pregnancy. Conclusion: The -863C/A and -238G/A TNF-α polymorphisms are possible genetic risk factors of recurrent pregnancy loss and might be its predictive markers.