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bioRxiv · 10.1101/197731

Mitochondrial Methylation Two-Peak Profile Absent in Parkinson's Disease Patient

Valente, A. X. C. N.·Liao, Q.·Rohkin, G.·Bouca-Machado, R.·Guedes, L. C.·Ferreira, J. J.·Lee, S. M.-Y.
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Abstract

Whole-mitochondrial genome methylation profiles were obtained for mitochondrial DNA (mtDNA) from blood samples of one sporadic Parkinsons Disease (PD) patient and one healthy control donor, via Whole-Genome Next-Generation Bisulfite Sequencing. Methylation frequency was determined at 836 CpG sites out of the 1146 CpG sites in mtDNA (73% of the total). The control mtDNA methylation profile exhibited a two-peak frequency distribution, with most CpG sites showing either no methylation, or a methylation above 7%. Instead, the sporadic PD mtDNA methylation profile exhibited a generic bell-shaped frequency distribution. The data is suggestive of the bell-shaped methylation profile arising via a degradation towards randomness of the healthy sample two-peak methylation pattern. Overall, this finding provides a possible explanation for the repeated observation of PD-phenotypic characteristics in cybrid cell lines where solely the mtDNA originates from a PD patient. We discuss the finding in terms of the sporadic PD Hematopoietic Origin Theory (HOT).

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Valente, A. X. C. N., Liao, Q., Rohkin, G., Bouca-Machado, R., Guedes, L. C., Ferreira, J. J., Lee, S. M.-Y.. 2017-10-03. Mitochondrial Methylation Two-Peak Profile Absent in Parkinson's Disease Patient. https://doi.org/10.1101/197731

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