Lack of association between the insulin receptor substrates-1 Gly972Arg polymorphism and type-2 diabetes mellitus among Saudis from Eastern Saudi Arabia

Objectives: To investigate the association between the insulin receptor substrate-1 (IRS1) Gly972Arg polymorphism and type-2 diabetes mellitus (T2DM) among Saudis from Eastern Saudi Arabia. Methods: This study was conducted between May and December 2014 at King Fahad Hospital of the University, Al-Khobar, Kingdom of Saudi Arabia. In a case-control study design, a total of 143 subjects (age range: 35-73 years) comprising 74 healthy controls and 69 patients with T2DM were examined. Blood samples were collected from subjects and subjected to genomic DNA extraction and chemical analysis. The IRS1 Gly972Arg polymorphism was then genotyped using the standard polymerase chain reaction-restriction fragment length polymorphism technique. Results: Eight out of 74 (10.8%) of the control group carried at least one copy of the mutated allele. The frequency (8.7%) of the IRS1 variant was also found in the diabetic group. Logistic regression analysis showed an adjusted odds ratio of 1.04, 95% confidence interval 0.28 - 3.95, and a p-value of 0.94. Conclusion: We failed to find any association between the IRS1 Gly972Arg polymorphism and T2DM.