Two point mutations in mitochondrial DNA of cytochrome c oxidase coexist with normal mtDNA in a patient with Alzheimer's disease

The mitochondrial cytochrome c oxidase (CO) gene sequence was determined on a patient with Alzheimer's disease (AD). Compared to the standard Cambridge sequence to identify base changes,two missense mutations were found in the patient with AD. The mutations were a G to T transition at np 8206 and an A to T transition at np 8224. The np 8206 mutation changed a Met to an Ile and np 8224 mutation changed a Leu to a Phe. The normal bases and the mutations of mitochondrial DNA (mtDNA) coexist in the patient. Further studies will be required to demonstrate the role of the point mutations of mitochondrial DNA in the pathogenesis of Alzheimer's disease.