Quantitative DSB sequencing (qDSB-Seq): a method for genome-wide accurate estimation of absolute DNA double-strand break frequencies per cell

Zhu, Y.; Dojer, N.; Biernacka, A.; Pardo, B.; Forey, R.; Skrzypczak, M.; Fongang, B.; Nde Kengne, J. B.; Yousefi, R.; Pasero, P.; Ginalski, K.; Rowicka, M.

doi:10.1101/171405

bioRxiv · 10.1101/171405

Quantitative DSB sequencing (qDSB-Seq): a method for genome-wide accurate estimation of absolute DNA double-strand break frequencies per cell

Zhu, Y.·Dojer, N.·Biernacka, A.·Pardo, B.·Forey, R.·Skrzypczak, M.·Fongang, B.·Nde Kengne, J. B.·Yousefi, R.·Pasero, P.·Ginalski, K.·Rowicka, M.

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Abstract

Sequencing-based methods for mapping DNA double-strand breaks (DSBs) allow measurement only of relative frequencies of DSBs between loci, which limits our understanding of the physiological relevance of detected DSBs. We propose quantitative DSB sequencing (qDSB-Seq), a method providing both DSB frequencies per cell and their precise genomic coordinates. We induced spike-in DSBs by a site-specific endonuclease and used them to quantify labeled DSBs (e.g. using i-BLESS). Utilizing qDSB-Seq, we determined numbers of DSBs induced by a radiomimetic drug and various forms of replication stress, and revealed several orders of magnitude differences in DSB frequencies. We also measured for the first time Top1-dependent absolute DSB frequencies at replication fork barriers. qDSB-Seq is compatible with various DSB labeling methods in different organisms and allows accurate comparisons of absolute DSB frequencies across samples.

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Zhu, Y., Dojer, N., Biernacka, A., Pardo, B., Forey, R., Skrzypczak, M., Fongang, B., Nde Kengne, J. B., Yousefi, R., Pasero, P., Ginalski, K., Rowicka, M.. 2017-08-11. Quantitative DSB sequencing (qDSB-Seq): a method for genome-wide accurate estimation of absolute DNA double-strand break frequencies per cell. https://doi.org/10.1101/171405

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