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Multiple mitochondrial DNA deletions in monozygotic twins with OPMD
M M K Muqit1, A J Larner, M G Sweeney
1Division of Clinical Neurosciences and Psychological Medicine, Imperial College London, UK.
Journal of Neurology, Neurosurgery, and Psychiatry
|June 7, 2007
Summary
Mitochondrial DNA deletions are present in Oculopharyngeal muscular dystrophy (OPMD) patients, correlating with disease severity. These genetic changes in mitochondrial DNA (mtDNA) may explain varying OPMD phenotypes.
Area of Science:
- Genetics
- Neurology
- Mitochondrial Biology
Background:
- Oculopharyngeal muscular dystrophy (OPMD) is a genetic disorder linked to PABP2 gene expansions.
- Mitochondrial abnormalities are observed in OPMD patients, but their role is unclear.
Observation:
- Studied monozygotic twins with identical PABP2 gene expansions but differing OPMD severity.
- Both twins exhibited histological signs of mitochondrial myopathy.
Findings:
- First demonstration of mitochondrial DNA (mtDNA) deletions in OPMD patients using Southern blotting.
- Identified distinct mtDNA deletions in each twin, potentially explaining phenotypic variations.
Implications:
- Mitochondrial dysfunction may result from PABP2 gene mutations in OPMD.
- Mitochondrial dysfunction could influence the diverse clinical presentations of OPMD.
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