We describe a second patient carrying the 5698G→A transition in the mitochondrial DNA gene encoding tRNA Asn, who has an apparently isolated mitochondrial myopathy with chronic progressive external ophthalmoplegia. A muscle biopsy showed the presence of ragged-red and COX-negative fibres. Analysis of the mutation load on single muscle fibres showed significant segregation of the 5698G→A with COX-depleted fibres. These results indicate that the 5698G→A is pathogenic.
- Chronic progressive external ophthalmoplegia
- Mitochondrial myopathy
- Point mutation
ASJC Scopus subject areas
- Clinical Neurology
- Pediatrics, Perinatology, and Child Health
- Developmental Neuroscience