RESUMO
<p><b>OBJECTIVE</b>To explore the relationship between type 2 diabetes mellitus (T2DM) and the mutations in the fragment of mitochondrial DNA (mtDNA) from nucleotides 3153 to 3551, which have shown high frequency of point mutation.</p><p><b>METHODS</b>One hundred and ninety-one normal controls and 222 patients with T2DM were screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), T-A cloning sequencing and denatured high performance liquid chromatography (DHPLC) techniques.</p><p><b>RESULTS</b>The prevalence of mtDNA mutations in the patient group (24.32%) was significantly higher than that in the control group (7.33%) (P < 0.05). Three novel mutations of A3209T, T3253G and A3467C were found, and C3497T was first reported in DM. Onset age, body mass index, fasting blood glucose, HbA1C, high density lipoprotein-cholesterol and diabetic nephropathy could be related to occurrence of mtDNA mutations (P < 0.05).</p><p><b>CONCLUSION</b>Mitochondrial DNA mutations might implicate T2DM in Wenzhou population, which should play an important role in the pathogenesis of T2DM.</p>