Mitochondrial myopathy in a child with a muscle-restricted mutation in the mitochondrial transfer RNA(Asn) gene

作者：Bruno Claudio^*; Cassandrini Denise; Fattori Fabiana; Pedemonte Marina; Fiorillo Chiara; Brigati Giorgia; Brisca Giacomo; Minetti Carlo; Santorelli Filippo M

来源：Biochemical and Biophysical Research Communications, 2011, 412(4): 518-521.

DOI：10.1016/j.bbrc.2011.06.155

• Mitochondrial myopathy
• mt-tRNA gene
• Exercise intolerance

We report an 11-year-old boy with exercise-related myopathy, and a novel mutation m.5669G>A in the mitochondrial tRNA Asparagine gene (mt-tRNA(Asn), MTTN). Muscle biopsy studies showed COX-negative, SDH-positive fibers at histochemistry and biochemical defects of oxidative metabolism. The m.5669G>A mutation was present only in patient's muscle resulting in the first muscle-specific MTTN mutation. Mt-tRNA(Asn) steady-state levels and in silico predictions supported the pathogenicity of this mutation. A mitochondrial myopathy should be considered in the differential diagnosis of exercise intolerance in children.

• 出版日期2011-9-9