Effect of Organic Cation Transporter 1 (OCT1) Polymorphism on Metabolic Response of Metformin in Iraqi Women with Polycystic Ovary Syndrome

Abstract

Background: Insulin-sensitizer treatment with metformin is widely used in polycystic ovary syndrome(PCOS). However, the treatment effectiveness shows individual differences in PCOS patients. Organiccation transporter (OCT1) have been reported to mediate metformin transport in the liver. Polymorphismsof OCT1 genes may affect the activity of metformin transport and further influence the treatment responseof metformin in PCOS patients.Materials and Method: In this study, we investigated the association between the polymorphism of OCT1and the treatment effectiveness of metformin in PCOS patients. The single nucleotide polymorphism (SNPs)of OCT1 – R61C analyzed in 222 PCOS and 106 control women. Fasting serum glucose (FSG), fastingserum insulin and HbA1c which represented metformin treatment response, were conducted at the start oftreatment and after three-month treatment.Results: The results demonstrated that the polymorphisms of OCT1 was associated with the variabilityof metformin response, most patients with reference allele (wild type) and heterozygous alleles of OCT1(R61C) showed statistically significant metabolic response to metformin, while patients with mutant allelesshowed less or statistically not significant response.Conclusion: Genetic polymorphisms of OCT1 contributed to different metformin treatment responses, andfurther study is needed to establish personalized treatment programs using a pharmacogenomic algorithmapproach in PCOS patients.