Infertility of unknown etiology is considered a significant medical and health problem. This study focused on the role of the estrogen receptor alpha (ESRα) gene polymorphism, PvuII (rs2234693), and its effect on the amount of ESRα in the blood of women who cannot get pregnant for unknown reasons. A total of 184 females were evaluated, including 102 with unexplained infertility (UI) and 82 age-matched control females (with at least one living child and no history of infertility). Blood samples were collected, genomic DNA was isolated from blood samples, and the genotyping of the ESRα gene was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). ESRα expression levels were assessed by the ELISA. The study revealed that the mean serum level of ESRα was significantly higher in the case group than in the control group (P<0.05). Furthermore, the genotypes (TT, TC, and CC) and alleles (T and C) significantly influenced the plasma level of ESRα in the study population. Moreover, the presence of the C allele was considered a risk factor, and the polymorphism had a significant effect on ESRα expression level in women with UI.
Keywords: Estrogen receptor alpha; Female infertility; Gene polymorphism; Genotyping; RFLP.