[Effect of mitochondrial DNA 5178 C/A polymorphism on risks for type 2 diabetes mellitus and its complications].

OBJECTIVE: To explore the role of mitochondrial DNA 5178 C/A (Mt5178) polymorphism of NADH-dehydrogenase subunit 2 (ND2) gene in type-2 diabetes mellitus (T2DM) among ethnic Han Chinese through a case-control study.

METHODS: The Mt5178C/A polymorphism was determined by sequencing 1103 T2DM patients and 791 healthy controls. Logistic regression analysis was conducted to estimate odds ratios (OR) and 95% confidence intervals (CI). To confirm the results, a meta-analysis was conducted based on published literature on the association of Mt5178 variant with T2DM.

RESULTS: No significant association was found between the Mt5178C/A variant and T2DM either by our study or the meta-analysis which included eight published studies. Nevertheless, it was found that the T2DM patients with 5178C genotype were at a higher risk for nephropathy complication (OR=1.49, 95%CI: 1.005-2.197, P<0.05) and at significantly lower risk for hypertension complication (OR=0.744, 95%CI: 0.556-0.996, P<0.05) compared with those carrying a 5178A genotype.

CONCLUSION: No association was found between the Mt5178C/A polymorphism of mitochondrial ND2 gene with the increased risk of T2DM. However, the polymorphism may affect the development of nephropathy and hypertension complications among T2DM patients.