A case-control study in IL6 and TGFB1 gene polymorphisms and recurrent spontaneous abortion in southern Brazilian patients

PROBLEM: A high proportion of recurrent spontaneous abortions (RSA) remains unexplained. Cytokine genotyping has been investigated. We studied the relationship between unexplained RSA, IL6 (-174 G-->C) and TGFB1 (+869, T-->C; +915, G-->C) gene polymorphisms. METHOD OF STUDY: The case-control study composed of 57 south Brazilian women, with unexplained RSA and 74 controls carefully matched was performed. Cytokine genotyping was performed by the polymerase chain reaction-sequence specific primer method, using the 'Cytokine Genotyping Tray'. RESULTS: The results showed that the genotypic frequencies did not differ from samples for TGFB1 gene. In relation to IL6 gene polymorphism there was a statistical difference in genotypic distribution between samples (P less than or equal to 0.025). The frequency of the C/C genotype was increased in women with RSA in comparison with the frequency observed in controls: 18% versus 4% (P = 0.01). CONCLUSIONS: This result strengthened the importance of IL6 genotypes in the pathogenesis of RSA of unknown cause in the south Brazilian population.