Mutation analysis of CHCHD2 and CHCHD10 in Italian patients with mitochondrial myopathy

Mutations in CHCHD2 and CHCHD10 were recently reported in a broad spectrum of neurodegenerative diseases, for example, Parkinson's disease, amyotrophic lateral sclerosis, frontotemporal dementia, or mitochondrial myopathy (MM). The aim of the study was to evaluate the prevalence of CHCHD2 and CHCHD10 mutations in Italian MM patients without mitochondrial DNA mutations. The coding regions of CHCHD2 and CHCHD10 were sequenced in 62 MM patients. None of the patients showed CHCHD2 mutations, whereas 1 sporadic MM patient carried a homozygous Pro96Thr substitution in CHCHD10. Muscle biopsy of this patient showed intracellular glycogen accumulation with cytochrome c oxidase negative and ragged red fibers. Our study suggests that the homozygous Pro96Thr mutation in CHCHD10 might be pathogenic but does not support a major role for CHCHD2 in MM pathogenesis.