title: Subacute necrotizing encephalopathy: oxidative phosphorylation defects and the ATPase 6 point mutation.
abstract: Subacute necrotizing encephalopathy (SNE) or Leigh's disease is associated with various defects in oxidative phosphorylation (OXPHOS). However, the relationships between these OXPHOS defects and nuclear DNA or mitochondrial DNA (mtDNA) mutations is still unclear. We evaluated three SNE pedigrees (two singleton cases and a pedigree) biochemically for OXPHOS abnormalities and genetically for four mtDNA point mutations. There was a complex I defect in all three pedigrees that was associated with a complex III defect in two individuals. An mtDNA mutation in the ATPase, subunit 6 gene (np 8993) was present in one SNE pedigree. This mutation was maternally inherited, heteroplasmic, produced marked clinical and biochemical heterogeneity between pedigree members, and varied along the maternal lineage at levels ranging from 0% to > 95% of the total mtDNAs. These mtDNA mutations were not present in the other two pedigrees. These observations emphasize the importance of screening for OXPHOS defects and mtDNA mutations in SNE cases.
authors.affiliation: Department of Genetics and Molecular Medicine, Emory University School of Medicine, Atlanta, GA 30329.
authors.forename: J M
authors.initials: JM
authors.lastname: Shoffner
authors.forename: P M
authors.initials: PM
authors.lastname: Fernhoff
authors.forename: N S
authors.initials: NS
authors.lastname: Krawiecki
authors.forename: D B
authors.initials: DB
authors.lastname: Caplan
authors.forename: P J
authors.initials: PJ
authors.lastname: Holt
authors.forename: D A
authors.initials: DA
authors.lastname: Koontz
authors.forename: Y
authors.initials: Y
authors.lastname: Takei
authors.forename: N J
authors.initials: NJ
authors.lastname: Newman
authors.forename: R G
authors.initials: RG
authors.lastname: Ortiz
authors.forename: M
authors.initials: M
authors.lastname: Polak
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics*; D015139:Blotting, Southern; D004272:DNA, Mitochondrial / Q000032:analysis; D005260:Female; D006801:Humans; D007223:Infant; D007888:Leigh Disease / Q000201:enzymology / Q000235:genetics*; D009132:Muscles / Q000201:enzymology; D009154:Mutation; D010085:Oxidative Phosphorylation; D010375:Pedigree; D016133:Polymerase Chain Reaction
chemical_list: D004272:DNA, Mitochondrial; D000251:Adenosine Triphosphatases