A novel mitochondrial ATP8 gene mutation in a patient with apical hypertrophic cardiomyopathy and neuropathy.
To identify the biochemical and molecular genetic defect in a 16-year-old patient presenting with apical hypertrophic cardiomyopathy and neuropathy suspected for a mitochondrial disorder.Measurement of the mitochondrial energy-generating system (MEGS) capacity in muscle and enzyme analysis in muscle and fibroblasts were performed. Relevant parts of the mitochondrial DNA were analysed by sequencing.A homoplasmic nonsense mutation m.8529G→A (p.Trp55X) was found in the mitochondrial ATP8 gene in the patient's fibroblasts and muscle tissue. Reduced complex V activity was measured in the patient's fibroblasts and muscle tissue, and was confirmed in cybrid clones containing patient-derived mitochondrial DNAWe describe the first pathogenic mutation in the mitochondrial ATP8 gene, resulting in an improper assembly and reduced activity of the complex V holoenzyme.
Jonckheere AI, Hogeveen M, Nijtmans L, van den Brand M, Janssen A, Diepstra H, van den Brandt F, van den Heuvel B, Hol F, Hofste T, Kapusta L, Dillmann U, Shamdeen M, Smeitink J, Smeitink J, Rodenburg R