No correlation between muscle A3243G mutation load and mitochondrial function in vivo.

P F Chinnery; D J Taylor; D Manners; P Styles; R Lodi

doi:10.1212/wnl.56.8.1101

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No correlation between muscle A3243G mutation load and mitochondrial function in vivo.

P F Chinnery·D J Taylor·D Manners·P Styles·R Lodi

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Abstract

The authors studied the relationship between the percentage level of A3243G mitochondrial DNA mutation and the degree of mitochondrial dysfunction in vivo in nine individuals from four pedigrees using phosphorus MRS in muscle. There was no significant correlation between mutation load and maximum rate of adenosine triphosphate production (V(max)). V(max) was normal in a subject with 32% A3243G in muscle, which is in contrast with a previous observation of markedly reduced V(max) in a patient with only 6% A3243G in muscle. Factors besides mutation load, such as nuclear genes, influence expression of the A3243G mutation in vivo.

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Adenosine Triphosphate Adult DNA, Mitochondrial Female Humans Magnetic Resonance Spectroscopy Male Middle Aged Mitochondrial Myopathies Muscle, Skeletal Pedigree Phosphorus Radioisotopes Point Mutation Statistics, Nonparametric Journal Article Research Support, Non-U.S. Gov't

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P F Chinnery, D J Taylor, D Manners, P Styles, R Lodi. 2001-04-24. No correlation between muscle A3243G mutation load and mitochondrial function in vivo.. https://doi.org/10.1212/wnl.56.8.1101

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