Associations of INPPL1 (+1893CC/AA and + 2945AA/GG) exonic polymorphisms with the risk of type 2 diabetes mellitus in North Indian population: A case control study

Abstract

Background and aim

INPPL1 gene encodes a lipid phosphatase Src homology 2-containing 5′-inositol phosphatase 2 (SHIP2) which is involved in the negative regulation of insulin signaling. In the light of several association studies of INPPL1 gene polymorphisms with T2DM, and the absence of association studies from India, present study was conducted to assess the association of two SNPs of INPPL1 gene with T2DM risk in North Indian population.

Material and method

Two single nucleotide polymorphism (SNPs) (+1893CC/AA and + 2945AA/GG) in INPPL1 gene were genotyped in total of 270 subjects with PCR-RFLP genotyping method.

Results

It was observed that, out of the two SNPs, only +1893CC/AA was found to be significantly associated with T2DM and frequency of A allele (C vs A, p = 0.002) has been found to be significantly higher in T2DM cases. Strong linkage disequilibrium was observed between two SNPs as assessed through D′ and r² (D′ = 0.984, r² = 0.009) and AG haplotype (OR = 3.59, 95% CI (1.59–9.80), p = 0.0015) was associated with increased risk of T2DM while CG haplotype (OR = 0.54, 95% CI (0.33–0.88) p = 0.012) significantly decreases the risk of developing T2DM. Regression analysis showed that SNP +1893CC/AA is associated with T2DM risk when adjusted for clinical/demographic variables.

Conclusion

Results showed that INPPL1 gene polymorphism +1893CC/AA may increase susceptibility to T2DM and ‘A' allele might be serving as a risk factor in development of T2DM in Indian population.