Absence of 4,977‐bp deletion of blood cell mitochondrial DNA in patients with young‐onset Parkinson's disease

Decreased mitochondrial Complex I activities and a 4,977‐bp deletion in mitochondrial DNA (mtDNA) have been reported in patients with Parkinson's disease. Based on the assumption of possible links between this 4,977‐bp deletion and the etiology of Parkinson's disease, we analyzed mtDNA of blood cells from 15 patients with young‐onset Parkinson's disease after the DNA was amplified by polymerase chain reaction. We could not detect the 4,977‐bp mtDNA deletion in any of these patients. This result suggests that Parkinson's disease is not a mitochondrial disease due to the 4,977‐bp mtDNA deletion. The 4,977‐bp deletion in mtDNA appears to be an age‐related phenomenon.