Background: Unexplained infertility refers to cases in which the standard diagnostic procedures available do not lead to a specific cause for the infertility. Gln223Arg polymorphism was associated with high serum leptin and consequently obesity, polycystic ovarian syndrome and infertility. The aim of this study was to investigate genetic variation of leptin receptor gene in unexplained infertile women. Materials and Methods: This case-control study was performed in 2015-2016. The subjects were 102 women with unexplained infertility and 112 fertile women with normal hormone profile. All participants gave their signature in consent document. After an overnight fasting, 5 CC blood sample was drawn from all subjects in the day 3 of menstruation. Genotyping of Gln223Arg polymorphism was performed using RFLP-PCR technique. Results: No significant association was observed between Gln223Arg polymorphism and unexplained infertility. The studied population was in Hardy-Weinberg equilibrium for Gln223Arg polymorphism. Therefore, there were not disturbing factors of Hardy-Weinberg equilibrium in the population. Conclusion: In present study, LEPR Gln223Arg polymorphism is not a risk factor for women with unexplained infertility. However, more studies on larger populations and the other leptin receptor polymorphism are suggested to understand the role of this polymorphism in women with unexplained infertility
