Impaired complex I assembly in a Leigh syndrome patient with a novel missense mutation in the ND6 gene.

Nijmegen Center for Mitochondrial Disorders, Department of Pediatrics, University Medical Center Nijmegen, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
Annals of Neurology (Impact Factor: 11.91). 12/2003; 54(5):665-9. DOI: 10.1002/ana.10734
Source: PubMed

ABSTRACT We describe a novel mutation in the ND6 gene (T14487C) in a patient with Leigh syndrome. Biochemical analyses indicated a low complex I activity in the patient's fibroblasts but normal values in muscle and liver. Cybrid clones showed a specific complex I defect that correlates with the mutant heteroplasmy levels. Additionally, we demonstrate an altered mobility and a decrease in the levels of fully assembled complex I in the patient's fibroblasts and cybrids, suggesting that the mutation has a profound effect on complex I assembly and/or stability.

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