C29T (Pro10Leu) Polymorphism of Transforming Growth Factor β1 (TGF-β1) Gene and Unexplained Infertility in Iran

The increasing incidence of infertility is alarming. About 10-30% of infertility are classified as Unexplained Infertility (UI) which is not an absolute clinical condition. TGF-b1 is multifunctional cytokine and produced mainly by T regulatory (Treg) lymphocytes. This cytokine plays important roles in physiology of normal pregnancy. The association of Single Nucleotide Polymorphisms (SNPs) of TGF-b1 gene with many immunologic diseases has been reported. In this study, the association of TGF-&beta1 C29T (Pro10Leu) gene polymorphism with unexplained infertility was investigated in Iranian UI patients. In this case-control study blood samples were collected from177 UI patients (142 male and 35 female) and 336 controls (232 male and 104 female) with no history of infertility. DNA was extracted by the salting out method. Analysis of the TGF-&beta1 gene polymorphism C29T (Pro10Leu) was performed by PCR and automated sequencing method. The genotype distributions and allele frequencies of TGF-b1 gene C29T (Pro10Leu) polymorphism were not statistically significant between different categories of UI patients and control group (p > 0.05). The results of this study showed, C29T (Pro10Leu) polymorphism of TGF-b1 gene may not associated with unexplained infertility and further studies are necessary to clarify the association of TGF-b1 polymorphisms and susceptibility to unexplained infertility.