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Mitochondrial myopathy associated with a novel 5522G>A mutation in the mitochondrial tRNA(Trp) gene.

ABSTRACT: We report a novel pathogenic mutation of the mitochondrial transfer RNA (tRNA) gene for tryptophan in a patient with isolated myopathy and persistently elevated creatine kinase. Muscle studies revealed ragged red fibres and decreased activity of respiratory chain complex I and cytochrome c oxidase (COX). Sequencing of the 22 mitochondrial tRNA genes revealed a mutation m.5522G>A, which alters a conserved base pairing in the D-stem of the tRNA for tryptophan. The mutation was heteroplasmic with a mutational load between 88 and 99% in COX-negative fibres. This case contributes to the genetic heterogeneity of mitochondrial diseases caused by mutations in mitochondrial tRNA genes.

SUBMITTER: Baric I

PROVIDER: S-EPMC3722682 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Mitochondrial myopathy associated with a novel 5522G>A mutation in the mitochondrial tRNA(Trp) gene.

Barić Ivo I Fumić Ksenija K Petković Ramadža Danijela D Sperl Wolfgang W Zimmermann Franz A FA Muačević-Katanec Diana D Mitrović Zoran Z Pažanin Leo L Cvitanović Šojat Ljerka L Kekez Tihomir T Reiner Zeljko Z Mayr Johannes A JA

European journal of human genetics : EJHG 20121212 8

We report a novel pathogenic mutation of the mitochondrial transfer RNA (tRNA) gene for tryptophan in a patient with isolated myopathy and persistently elevated creatine kinase. Muscle studies revealed ragged red fibres and decreased activity of respiratory chain complex I and cytochrome c oxidase (COX). Sequencing of the 22 mitochondrial tRNA genes revealed a mutation m.5522G>A, which alters a conserved base pairing in the D-stem of the tRNA for tryptophan. The mutation was heteroplasmic with a ...[more]

PMID: 23232693

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