Prevalence Pattern of Key Polymorphisms in the Vitamin D Receptor gene among Patients of Type 2 Diabetes Mellitus in Northeast India

AIMS: To investigate the association between Vitamin D receptor gene polymorphisms (BsmI, TaqI and FokI) and type 2 diabetes mellitus in patients in north eastern India. SETTINGS AND DESIGN: This was a case control study with 40 cases of type 2 diabetes and 20 controls. MATERIALS AND METHODS: Genomic DNA was extracted from blood and genotyped for the single nucleotide polymorphism (SNPs) of BsmI [rs1544410], TaqI [rs731236] and FokI [rs2228570] by polymerase chain reaction and gene sequencing. Genotype distribution and allelic frequencies were compared between patients and controls. Data was expressed as mean ±standard deviation. Chi square test and t test were used to compare groups. Statistical analysis was done using SAS version 9.3 software. P value of <0.05 was considered significant. RESULTS: Body weight and BMI were significantly associated with VDR polymorphisms BsmI and TaqI while BsmI was significantly associated with HbA1C. Vitamin D deficiency was significantly greater in cases than controls. The frequency of the heterozygous genotype of the BsmI polymorphism was significantly greater in type 2 diabetics than in controls. CONCLUSIONS: Vitamin D receptor polymorphisms are associated with type 2 diabetes in our population and require larger scale studies to be considered as possible risk factors or type 2 diabetes mellitus.