Parkinson syndrome, neuropathy, and myopathy caused by the mutation A8344G (MERRF) in tRNA(Lys)

Ruhr-Universität Bochum, Bochum, North Rhine-Westphalia, Germany
Neurology (Impact Factor: 8.29). 02/2007; 68(1):56-8. DOI: 10.1212/01.wnl.0000250334.48038.7a
Source: PubMed


We describe a patient who presented with parkinsonism associated with the A8344G myoclonus epilepsy, ataxia, and myopathy with ragged red fibers mutation in the tRNA(Lys) gene. In addition, neurogenic changes and mitochondrial myopathy with ragged red fibers were observed. Neither myoclonus epilepsy nor other clinical signs described in association with A8344G were noted. Similar to previously reported patients with parkinsonism and mtDNA deletions, the symptoms of our patient responded favorably to levodopa therapy.

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Available from: Rita Horvath, Sep 07, 2015
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    • "Although the role of mitochondrial dysfunction and mtDNA mutations in the pathogenesis of PD remains controversial, parkinsonism has been associated with several mtDNA mutations, including large-scale rearrangements (Casali et al. 2001; Chalmers et al. 1996; Siciliano et al. 2001) and point mutations or microdeletions (De Coo et al. 1999, Thyagarajan et al. 2000). A patient with parkinsonism associated with mitochondrial myopathy with ragged red fibers and harbouring the A8344G MERRF mutation in the tRNA Lys gene was recently reported (Horvath et al. 2007); no other clinical signs typical of MERRF were noted. Mutations in the nuclear-encoded mtDNA polymerase-c (POLG) gene impair mtDNA replication and result in multiple mtDNA deletions, typically causing chronic progressive external ophthalmoplegia and myopathy. "
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