Exercise intolerance associated with a novel 8300t>C mutation in mitochondrial transfer RNAlys

✍ Scribed by Michael J. Gambello; Ren-Kui Bai; Tian-Jian Chen; Mazen Dimachkie; Lee-Jun C. Wong

• Book ID: 102532774
• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 311 KB
• Volume: 34
• Category: Article
• ISSN: 0148-639X
• DOI: 10.1002/mus.20605

✦ Synopsis

Abstract

Mutations in the mitochondrial genome contribute to the pathophysiology of many neuromuscular diseases. Recently there has been an increased appreciation of the role of mitochondrial DNA (mtDNA) mutations in the etiology of exercise intolerance. Using TTGE (temporal temperature‐gradient gel electrophoresis) and sequence analyses of the entire mitochondrial genome, we identified a novel heteroplasmic mutation (8300T>C) in the tRNA^lys^ gene (MTTK) from a patient with unexplained exercise intolerance. The mutation was present in blood, hair, and muscle, with the highest percentage of heteroplasmy found in muscle. The results of muscle respiratory chain enzyme analysis are consistent with tRNA mutation. These data suggest that this novel mutation is yet another mtDNA mutation associated with muscle disease and should be considered in patients with similar symptoms. Muscle Nerve, 2006