A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Mutation m.15923A>G in the MT-TT gene causes mild myopathy - case report of an adult-onset phenotype
Tekijät: Mikko Kärppä, Laura Kytövuori, Markku Saari, Kari Majamaa
Kustantaja: BMC
Julkaisuvuosi: 2018
Lehti: BMC Neurology
Tietokannassa oleva lehden nimi: BMC NEUROLOGY
Lehden akronyymi: BMC NEUROL
Artikkelin numero: 149
Vuosikerta: 18
Sivujen määrä: 5
ISSN: 1471-2377
eISSN: 1471-2377
DOI: https://doi.org/10.1186/s12883-018-1159-4
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/35980067
Background: Only five patients have previously been reported to harbor mutations in the MT-TT gene encoding mitochondrial tRNA threonine. The m.15923A > G mutation has been found in three severely affected children. One of these patients died within days after birth and two had a phenotype of myoclonic epilepsy with ragged red fibers (MERRF) in early childhood. We have now found the mutation in an adult patient with mild myopathy.Case presentation: The patient is a 64-year-old Finnish man, who developed bilateral ptosis, diplopia and exercise intolerance in his fifties. Family history was unremarkable. Muscle histology showed cytochrome c-oxidase (COX) negative and ragged red fibres. The m.15923A > G mutation heteroplasmy was 33% in the skeletal muscle and 2% in buccal epithelial cells. The mutation was undetectable in the blood. Single-fibre analysis was performed and COX-negative fibres had a substantially higher heteroplasmy of 92%, than the normal fibres in which it was 43%.Conclusions: We report the fourth patient with m. 15923A > G and with a remarkably milder phenotype than the previous three patients. Our findings and recent biochemical studies suggest that the mutation m.15923A > G is a definite disease-causing mutation. Our results also suggest that heteroplasmy of the m.15923A > G mutation correlates with the severity of the phenotype. This study expands the catalog of the phenotypes caused by mutations in mtDNA.
Ladattava julkaisu This is an electronic reprint of the original article. |  |
