Darin N, Kollberg G, Moslemi A-R, Tulinius M, Holme E, Grönlund M Andersson, Andersson S, Oldfors A
Department of Pediatrics, Sahlgrenska University Hospital, Göteborg, Sweden.
Neuromuscul Disord. 2006 Aug;16(8):504-6. doi: 10.1016/j.nmd.2006.05.010. Epub 2006 Jun 27.
We describe a second patient with the 583G>A mutation in the tRNA(phe) gene of mitochondrial DNA (mtDNA). This 17-year-old girl had a mitochondrial myopathy with exercise intolerance and an asymptomatic retinopathy. Muscle investigations showed occasional ragged red fibers, 30% cytochrome c oxidase (COX)-negative fibers, and reduced activities of complex I+IV in the respiratory chain. The mutation was heteroplasmic (79%) in muscle but undetectable in other tissues. Analysis of single muscle fibers revealed a significantly higher level of mutated mtDNA in COX-negative fibers. Our study indicates that the 583G>A mutation is pathogenic and expands the clinical spectrum of this mutation.
我们描述了第二例线粒体DNA（mtDNA）的tRNA（phe）基因发生583G>A突变的患者。这名17岁女孩患有线粒体肌病，伴有运动不耐受和无症状视网膜病变。肌肉检查显示偶尔出现破碎红纤维、30%的细胞色素c氧化酶（COX）阴性纤维，以及呼吸链中复合物I+IV的活性降低。该突变在肌肉中为异质性（79%），但在其他组织中未检测到。对单根肌纤维的分析显示，COX阴性纤维中的突变mtDNA水平显著更高。我们的研究表明，583G>A突变具有致病性，并扩大了该突变的临床谱。
