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bioRxiv · 10.1101/2021.02.10.430587

Biased nicking of mitochondrial DNA during extraction can be avoided by choice of isolation method

Repoles, B. M.·Gorospe, C. M.·Tran, P.·Nilsson, A. K.·Wanrooij, P. H.
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Abstract

The integrity of mitochondrial DNA (mtDNA) isolated from solid tissues is critical for analyses such as long-range PCR, but is typically assessed under conditions that fail to provide information on the individual mtDNA strands. Using denaturing gel electrophoresis, we show that commonly-used isolation procedures generate mtDNA containing several single-strand breaks per strand. Through systematic comparison of DNA isolation methods, we identify a procedure yielding the highest integrity of mtDNA that we demonstrate displays improved performance in downstream assays. Our results highlight the importance of isolation method choice, and serve as a resource to researchers requiring high-quality mtDNA from solid tissues.

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Repoles, B. M., Gorospe, C. M., Tran, P., Nilsson, A. K., Wanrooij, P. H.. 2021-02-10. Biased nicking of mitochondrial DNA during extraction can be avoided by choice of isolation method. https://doi.org/10.1101/2021.02.10.430587

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