The ‘common deletion’ is not increased in parkinsonian substantia nigra as shown by competitive polymerase chain reaction
✍ Scribed by Siegfried Kösel; Rupert Egensperger; Nina M. Schnopp; Dr. Manuel B. Graeber
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 710 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0885-3185
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Previous studies have estimated levels of mitochondrial DNA (mtDNA) carrying the 4,977‐base‐pair 'common deletion' in tissues from patients with Parkinson's disease (PD) by using semiquantitative techniques. The role of this deleted mtDNA species in the pathogenesis of PD has remained controversial. We have applied competitive polymerase chain reaction to achieve exact quantitation of deleted mtDNA in the substantia nigra and additional brain regions of cases with neuropathologically confirmed Lewy‐body parkinsonism, In addition, genotyping was carried out for CYP2D6^G1,934A^ and CYP2D6^C2,938T^alleles and the mitochondrial ND2 (nucleotide 5,460) and transfer RNA for glutamine (nucleotide 4,336) sequence variants. Parkinsonian brains showed 1–3% deleted mtDNA in the substantia nigra, that is, deletion levels were not higher than in age‐matched controls. Our findings suggest that the defect in complex I of the respiratory chain observed in PD is not primarily due to the ‘common deletion’.