TNF-α (g.−308 G > A) and ADIPOQ (g. + 45 T > G) Gene Polymorphisms in Type 2 Diabetes and Microvascular Complications in the Region of Punjab (North–West India)

Abstract

Aims: The present study aims to examine the association of tumor necrosis factor-α (TNF-α) g.−308 G > A and adiponectin (ADIPOQ) g. + 45 T > G gene polymorphisms in type 2 diabetes (T2D) and its microvascular complications diabetic retinopathy (DR) and diabetic nephropathy (DN).

Materials and Methods: A total of 672 individuals were analysed from the North–West population of Punjab. Genotyping was accomplished by a combination of allele specific amplification refractory mutation system and restriction digestion for TNF-α g. − 308 G > A and ADIPOQ g. + 45 T > G polymorphisms, respectively. Further, in silico modeling was done to predict secondary structure of mRNA for g. + 45 T > G polymorphism in the ADIPOQ gene by RNA fold.

Results: The minor allele frequency observed in the controls for the TNF-α G > A and ADIPOQ T > G polymorphisms were 0.07 and 0.10, respectively. The results show no significant association with TNF-α g. − 308 G > A polymorphism in T2D as well as in any of the microvascular complication. However, the ADIPOQ g. + 45 T > G polymorphism shows significant association in T2D (p = 0.048) and DR (p = 0.001) but in DN patients, no association was observed. Interactive analysis revealed that the two polymorphisms jointly conferred a 1.45-fold risk towards the occurrence of T2D [p = 0.031; OR = 1.45 (1.03–2.05)]. In the secondary structure of mRNA, slight free energy change was observed between the wild ( − 1370.28 kcal/mol) and variant allele (−1369.08 kcal/mol).

Conclusions: Our results indicated a higher risk of T2D and DR in the background of ADIPOQ TT genotype. Further, the ADIPOQ g. + 45 T > G and TNF-α g. − 308 G > A polymorphisms jointly give 1.45-fold risk towards T2D.

• Diabetic nephropathy
• diabetic retinopathy
• North–West Indian population
• SNP
• type 2 diabetes

Acknowledgements

The financial assistance to R. Sikka under UGC-SAP and P. Raina under DST-INSPIRE programme is acknowledged.