Department of Neurology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905, USA.
J Neurol Sci. 2012 Aug 15;319(1-2):158-63. doi: 10.1016/j.jns.2012.05.003. Epub 2012 May 24.
We report a novel heteroplasmic mutation p.Y440C in the mitochondrial DNA-encoded subunit I of the cytochrome c oxidase (COX) gene in a patient with late onset progressive painless weakness. Her muscle biopsy showed scattered COX-negative fibers and several small collections of inflammatory cells. The mutation was detected in the patient's muscle but not in her blood. The low mutant load in muscle could explain the patient's late onset of the myopathy and milder phenotype when compared to the previously published cases with MTCO1 mutations.
我们报告了一例新的线粒体 DNA 编码细胞色素 c 氧化酶（COX）亚基 I 中的异质突变 p.Y440C，该患者患有晚期起病的进行性无痛性无力。她的肌肉活检显示散在的 COX 阴性纤维和几处小的炎症细胞簇。该突变仅在患者的肌肉中被检测到，而不在血液中。与先前报道的 MTCO1 突变病例相比，肌肉中的突变负荷较低可能解释了该患者肌病的晚期起病和较轻的表型。
