Somatic mitochondrial DNA mutations in early Parkinson and incidental Lewy body disease.

Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, NY, USA.
Annals of Neurology (Impact Factor: 11.91). 06/2012; 71(6):850-4. DOI: 10.1002/ana.23568
Source: PubMed

ABSTRACT Somatic mutations in mitochondrial DNA (mtDNA) are hypothesized to play a role in Parkinson disease (PD), but large increases in mtDNA mutations have not previously been found in PD, potentially because neurons with high mutation levels degenerate and thus are absent in late stage tissue. To address this issue, we studied early stage PD cases and cases of incidental Lewy body disease (ILBD), which is thought to represent presymptomatic PD. We show for the first time that mtDNA mutation levels in substantia nigra neurons are significantly elevated in this group of early PD and ILBD cases.

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