Cytokine gene variants of TNF-α and IL-10 in the propensity of type 2 diabetes in south Indian population.

Chronic inflammation plays an important role in type 2 diabetes mellitus (T2DM), a common endocrinological pro-inflammatory disorder associated with insulin resistance. The objective of the present study is to see individual and combined effect of TNF-α (rs361525, rs1800629) and IL-10 (rs1800872, rs1800896) genes on T2DM susceptibility The genotyping was carried out in 200 T2DM patients and 200 healthy controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using suitable primers. The results shown that TNF-α (GA of rs361525 & rs1800629) and IL-10 (AA of rs1800872 & GA of rs1800896) genes are significantly linked with T2DM development. The presence of AA-GA genotype combination for both TNF-α and IL-10 genes were elevating the risk of T2DM. Moreover, individuals bearing haplotypes AAAA, AACA and AAAG experience the increased risk of T2DM. Furthermore, gene-gene interaction analysis shown that TNF-α (GA of rs361525 & rs1800896) gene redundantly confer 3.4-fold elevated risk for T2DM. In gene-environment interaction, GA of TNF-α -1800896, W/H ratio and TG/HDL ratio were redundantly interacted each other and increase the risk of T2DM by 67-times. In conclusion, our results reveal that there is a significant association between foresaid TNF-α, IL-10 gene promoter polymorphisms and T2DM development. To the best of our knowledge this study is the first of its kind in the literature reporting the epistatic association of TNF-α (rs1800629G/A) gene with TG/HDL ratio and W/H ratio over IL-10 gene polymorphisms for T2DM susceptibility among south Indians.