Relationship between Prolactin rs1341239 Gene Polymorphism and Prolactin Serum Level in Iranian Patients with Systemic Lupus Erythematosus

Abstract

Background: Systemic lupus erythematosus (SLE) as an inflammatory autoimmune disease, originates from the production of autoantibodies against several cellular components, especially nuclear components such as DNA. Prolactin consists of 199 amino acids and due to the structural similarity with cytokines, this polypeptide has the ability to modulate the immune system, which is characterized by the observation of hyperprolactinemia in autoimmune disorders. The rs1341239 polymorphism of the prolactin gene is associated with several autoimmune diseases. The purpose of this study is to investigate the relationship between this polymorphism and prolactin serum level in SLE patients in a population from Iran. Methods: Genotype analysis of prolactin rs1341239 gene polymorphism was performed using blood samples of 90 SLE patients as patients’ group and 90 control samples as the control group through RFLP-PCR method. Also, serum prolactin concentration was measured using ELISA method. Results: Our results showed a significantly higher serum level of prolactin in patients group than in the control group. There was no significant difference in alleles and genotypes frequencies of rs1341239 polymorphism in patients group compared to the control group. However, a significant correlation was found between the frequency of GG genotype and the reduction of platelets in the blood of patients group. Conclusion: Our results did not show a significant difference in the frequency of prolactin rs1341239 gene polymorphism in patients and control groups, while we observed the relationship between this polymorphism and platelet count in patients group.