Association of vitamin D receptor gene polymorphism with young onset diabetes millitus in a Bangladeshi population

Abstract

Vitamin D has an important immunomodulatory property and also has been suggested to play an important role in cellular metabolism. Vitamin D receptor (VDR) gene polymorphism has also been found to be associated with insulin secretory capacity and glucose intolerance. The present study was undertaken to determine genotype of VDR gene common variants in young onset diabetic subjects of Bangladesh to explore its association with diabetes and B cell secretory capacity. A total number of 94 young diabetic subjects and 92 healthy controls were recruited. Detailed clinical and anthropometric measurements were recorded. Blood glucose was measured by glucoseoxidase, lipids by standard methods. C-peptide was estimated by enzyme linked immunosorbent assay (ELISA), and insulin secretory capacity (HOMA%B), sensitivity (HOMA%S), resistance (HOMA-IR) were calculated using VIOMA Sigma software. DNA was extracted using QIAGEN Blood DNA Kit. VDR gene variants [G>T and T>C] were determined by PCR-RFLP using restriction endonuclease Apal and Taq) respectively. Data were managed using Statistical Program for Social Science (SPSS). Unpaired Student's -`t' test and Chi-squared tests, as appropriate, were performed. Cpeptide level was found to be significantly lower 3.297 (p<0.001) and I-IOMA%B found lower 3.102 (p=0.003). The G>T and T>C genome frequencies (wild, heterozygous and homozygous variants) were in the control (0.183, 0.5 16, 0.3 16 and 0.370, 0.522, 0.109 respectively) and (0.198, 0.484, 0.319 and 0.484, 0.418, 0.090 respectively) in YDM which did not show significant association with YDM (p=0.906 and 0.288 respectively). Genotype frequency of the marker allele did not show significant association with glucose, C-peptide, 1IOMA%S and IR either in Controls or YDM subjects except the HOMA%B shown to have relatively lower.