Allele Frequency of a Common Variants and Two Common Loss-of-Function Variants in Organic Cation Transporter 1 (OCT1) among Balinese Diabetic Patients
Sri Agung Aryastuti1*
, Erly Sintya2, Asri Lestarini2 and Ni Putu Diah Witari31Department of Pharmacology, Faculty of Medicine and Health Sciences, Universitas Warmadewa, Indonesia, 80235
2Department of Biochemistry, Faculty of Medicine and Health Sciences, Universitas Warmadewa, Indonesia, 80235
3Department of Histology, Faculty of Medicine and Health Sciences, Universitas Warmadewa, Indonesia, 80235
Corresponding Author E-mail: sriagungary@gmail.com
Abstract: Metformin is the most common drug prescribed for patient with type 2 diabetes mellitus (T2DM). Although it is widely used as first line therapy for T2DM, there were huge variations in its clinical efficacy among population. It was postulated that genetic polymorphisms of metformin transporter, especially organic cation transporter 1 (OCT1) encoded by SLC22A1 gene, have a considerable effect on respon of metformin therapy. However, data for this polymorphism in Balinese population was not well established. The aim of this study was to identify genetic variation in OCT1, especially rs628031, rs122083571, and rs623442, in Balinese diabetic patients. It was a descriptive study to explore genetic variation in OCT1 encoded by SLC22A1 gene. A total of 133 diabetic patients were recruited from Departement of Internal Medicine at Sanjiwani Hospital Gianyar and Tabanan Hospital, Bali. DNA was extracted and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to assess the polymorphism rs628031. While, polymorphism rs122083571 and rs623442 were assessed by direct sequencing. The minor allele frequency (MAF) for polymorphism rs628031 in this population was 0.59 with genotype frequency of AA, AG, and GG accounted for 16.5%; 48.9%, and 34.6% respectively. Minor allele frequency for polymorphism rs623442 was 0.20 with genotype frequency of CC, CA, and AA 5.4%; 29.0%; and 65.6% respectively. Polymorphism rs122083571 was not found in this population (100% genotype CC). Genetic polymorphism of OCT1 rs628031 in this population was occurred in relatively high frequency, while polymorphism OCT1 rs623442 was occurred only in one fifth of studied population. Further studies are needed to address the effect of this polymorphism to therapeutic respons of metformin in Balinese population.
Keywords: OCT1 polymorphism; rs628031; rs623442; rs122083571; type 2 diabetes mellitus Back to TOC