Novel mitochondrial 16S rRNA mutation, 3200T-->C, associated with adult-onset type 2 diabetes

• Published in: Chinese medical journal Vol. 115; no. 5; p. 753
• Main Authors: Yang, Tao, Lam, Ching-Wan, Tsang, Man-Wo, Tong, Sui-Fan, Kam, Grace Y W, Chan, Lisa Y S, Poon, Priscilla M K, Wu, Xiangqian, Pang, Chi-Pu
• Format: Journal Article
• Language: English
• Published: China 01.05.2002
• Subjects: Age of Onset; Aged; Alleles; Base Sequence; Diabetes Mellitus, Type 2 - genetics; DNA Mutational Analysis; DNA, Mitochondrial - chemistry; DNA, Mitochondrial - genetics; Humans; Middle Aged; Models, Molecular; Nucleic Acid Conformation; Point Mutation; Polymerase Chain Reaction - methods; Polymorphism, Restriction Fragment Length; RNA, Ribosomal, 16S - chemistry; RNA, Ribosomal, 16S - genetics
• ISSN: 0366-6999

To investigate the role of a potential diabetes-related mitochondrial region, which includes two previously reported mutations, 3243A-->G and 3316G-->A, in Chinese patients with adult-onset type 2 diabetes. A total of 277 patients and 241 normal subjects were recruited for the study. Mitochondrial nt 3116 - 3353, which spans the 16S rRNA, tRNA(leu(UUR)) and the NADH dehydrogenase 1 gene, were detected using polymerase chain reaction (PCR), direct DNA sequencing, PCR-restriction fragment length polymorphism and allele-specific PCR. Variants were analyzed by two-tailed Fisher exact test. The function of the variants in 16S rRNA were predicted for minimal free energy secondary structures by RNA folding software mfold version 3. Four homoplasmic nucleotide substitutions were observed, 3200T-->C, 3206C-->T, 3290T-->C and 3316G-->A. Only the 3200T-->C mutation is present in the diabetic population and absent in the control population. No statistically significant associations were found between the other three variants and type 2 diabetes. The 3200T-->C and 3206C-->T nucleotide substitutions located in 16S rRNA are novel variants. The 3200T-->C caused a great alteration in the minimal free energy secondary structure model while the 3206C-->T altered normal 16S rRNA structure little. The results suggest that the 3200T-->C mutation is linked to the development of type 2 diabetes, but that the other observed mutations are neutral. In contrast to the Japanese studies, the 3316G-->A does not appear to be related to type 2 diabetes.