Association of genetic polymorphisms in vitamin D receptor (, and ) with vitamin D and glycemic status in type 2 diabetes patients from Southern India.

OBJECTIVES

To evaluate the association of polymorphisms (, and ) with vitamin D levels and glycemic status in type 2 diabetes patients from Southern India.

METHODS

In this observational study, genotype frequencies and vitamin D levels of 200 cases (type 2 diabetes patients) were compared with 300 controls (unrelated anonymised stored samples of healthy volunteers) from south India. Serum 25 (OH) D levels were measured by immunoassay technique, glycated hemoglobin (HbA) was measured using HPLC and genotyping of VDR polymorphisms were carried out using Real time Polymerase Chain Reaction (RT PCR).

RESULTS

About 69.2% of type 2 diabetes patients were found to have vitamin D deficiency. polymorphism showed variations in serum 25 (OH) D levels, with AA and AG genotypes having significantly lower serum 25 (OH) D levels as compared to GG [13.24 (8.4) ng/ml, 15.02 (7.07) ng/ml and 20.67 (13.64) ng/ml respectively]. There was no difference in HbA levels with respect to the vitamin D levels and VDR polymorphisms.

CONCLUSIONS

AA and AG genotypes of polymorphisms are associated with low serum 25 (OH) D levels. However there was no association between VDR polymorphisms and glycemic status in south Indian type 2 diabetes patients.