The T9861C Mutation in the mtDNA-Encoded Cytochrome C Oxidase Subunit III Gene Occurs in High Frequency but with Unequal Distribution in the Alzheimer's Disease Brain.

Mitochondrial dysfunction is recognized as a critical component in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). Deficits in oxidative capacity and, specifically, cytochrome c oxidase (CO) activity have been reported in AD brains and platelets. We previously identified a point mutation at np 9861 in AD brain mitochondrial DNA (mtDNA) that alters amino acid 219 of subunit III of CO from phenylalanine to leucine.