Association study of mitochondrial DNA polymorphisms with type 2 diabetes in Tunisian population

Abstract

Mitochondrial DNA (mtDNA) variation may play an important role in the pathogenesis of type 2 diabetes (T2Ds). In this study, we aimed to explore whether mtDNA variants contribute to the susceptibility to T2Ds in a Tunisian population. The hypervariable region 1 (HVS1) of the mtDNA of 64 T2Ds patients and 77 healthy controls was amplified and sequenced. Statistical analysis was performed using the STATA program. Analysis of the total screened variants (N = 88) from the HVS1 region showed no significant difference in the distribution of all polymorphisms between T2Ds and controls, except for the variant G16390A which was more frequent in T2Ds (15.9%) than in controls (5.4%) (p = 0.04). The association of G16390A was not detected after multivariate regression analysis. Similarly, analysis of the distribution of mitochondrial haplogroups within our dataset showed 18 distinct major haplogroups with no significant difference between T2Ds and controls. Except, the weakly association found for the G16390A variant, our results showed that none of the tested polymorphisms from the HVS1 region have a major role in T2Ds pathogenesis in the studied Tunisian population even when taking into account the population stratification.

Keywords: Hypervariable region 1; North Africa; Tunisia; mitochondrial DNA; type 2 diabetes.