Mitochondrial tRNALeu(UUR) Mutation at Position 3243 and Symptomatic Polyneuropathy in Type 2 Diabetes

In 1994, we documented a high frequency of complicated posttreatment neuropathy in patients with mitochondrial diabetes associated with tRNALeu(UUR) mutation at position 3243′ (MDM3243) (1). Thereafter, experimental studies accumulated evidence that mitochondria are a major culprit in the initiation and development of complications of diabetes through oxidative stress or altered redox changes (2–4). We recently confirmed our previous observation on the association of mitochondrial DNA (mtDNA) mutation with clinical symptoms of diabetic distal polyneuropathy by conducting a large-scale study. A total of 271 Japanese patients with type 2 diabetes at Saiseikai Central Hospital were subjected and divided into two groups. Patients who had leg symptoms not only at the time of this study, but also in their history were regarded as positive and were classified into group 1. Symptomatic neuropathy was assessed by the presence of one, two, or all of the following symptoms over a previous 5-year period: numbness in the feet, pricking sensation in the feet, …