A novel pathogenic m.4412G>A MT-TM mitochondrial DNA variant associated with childhood-onset seizures, myopathy and bilateral basal ganglia changes.
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ABSTRACT:
SUBMITTER: Lim AZ
PROVIDER: S-EPMC6617384 | biostudies-literature | 2019 Jul
REPOSITORIES: biostudies-literature
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A novel pathogenic m.4412G>A MT-TM mitochondrial DNA variant associated with childhood-onset seizures, myopathy and bilateral basal ganglia changes.
Lim Albert Z AZ Blakely Emma L EL Baty Karen K He Langping L Hopton Sila S Falkous Gavin G McWilliam Kenneth K Cozens Alison A McFarland Robert R Taylor Robert W RW
Mitochondrion 20190422
Mitochondrial DNA variants in the MT-TM (mt-tRNA<sup>Met</sup>) gene are rare, typically associated with myopathic phenotypes. We identified a novel MT-TM variant resulting in prolonged seizures with childhood-onset myopathy, retinopathy, short stature and elevated CSF lactate associated with bilateral basal ganglia changes on neuroimaging. Muscle biopsy confirmed multiple respiratory chain deficiencies and focal cytochrome c oxidase (COX) histochemical abnormalities. Next-generation sequencing ...[more]
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