Polymorphisms of Cytokine Genes and Polycystic Ovary Syndrome: A Review

Background: Polycystic ovary syndrome (PCOS) is the endocrinopathy that affects women in their reproductive age. The physiopathology involves multifactorial mechanisms, including cytokine gene regulation. Methods: The review was conducted in the database PubMed, with articles published between 2005 and 2015. The selected studies evaluated the single-nucleotide polymorphisms (SNPs) of cytokines genes in association with PCOS. Twenty-four studies met the inclusion criteria and showed the SNPs of cytokines that were associated or not with PCOS. Results: The disease susceptibility was associated with interleukin (IL) 1A, IL1B, IL1RN, and IL6 alleles and genotypes. The tumor necrosis factor (TNF) -1032 C/T genotype and C allele were risk factors and T/T genotype was a protector marker to disease. The IL18 SNPs were not associated with PCOS per se, but IL18-137 C and G alleles were related to the protection of insulin resistance and glucose tolerance, respectively. One research found association between TGFB1 and PCOS. However, the TNF -308, IL10, and interferon (IFN) SNPs did not appear to influence PCOS genetic susceptibility. Conclusions: This study sought to contribute and clarify the SNPs in cytokine genes that influence the development of PCOS. Most studies occurred in Asia; most SNPs studied were in IL1B -511, TNF -1031, and IL6-174; and most of them were associated with the susceptibility to PCOS development. Nevertheless, further investigations based on genome-wide association studies and cytokine gene SNPs are needed to better characterize the risk factors to PCOS.