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Measuring DNA modifications with the comet assay: a compendium of protocols.

Collins, Andrew; Møller, Peter; Gajski, Goran; Duthie, Susan J.


Andrew Collins

Peter Møller

Goran Gajski


The comet assay is a versatile method to detect nuclear DNA damage in individual eukaryotic cells, from yeast to human. The types of damage detected encompass DNA strand breaks and alkali-labile sites (e.g., apurinic/apyrimidinic sites), alkylated and oxidized nucleobases, DNA–DNA crosslinks, UV-induced cyclobutane pyrimidine dimers and some chemically induced DNA adducts. Depending on the specimen type, there are important modifications to the comet assay protocol to avoid the formation of additional DNA damage during the processing of samples and to ensure sufficient sensitivity to detect differences in damage levels between sample groups. Various applications of the comet assay have been validated by research groups in academia, industry and regulatory agencies, and its strengths are highlighted by the adoption of the comet assay as an in vivo test for genotoxicity in animal organs by the Organisation for Economic Co-operation and Development. The present document includes a series of consensus protocols that describe the application of the comet assay to a wide variety of cell types, species and types of DNA damage, thereby demonstrating its versatility.


COLLINS, A., MØLLER, P., GAJSKI, G., DUTHIE, S.J. et al. 2023. Measuring DNA modifications with the comet assay: a compendium of protocols. Nature protocols [online], 18, pages 929-989. Available from:

Journal Article Type Review
Acceptance Date Jul 5, 2022
Online Publication Date Jan 27, 2023
Publication Date Dec 31, 2023
Deposit Date Feb 6, 2023
Publicly Available Date Jul 28, 2023
Journal Nature protocols
Print ISSN 1754-2189
Electronic ISSN 1750-2799
Publisher Springer
Peer Reviewed Peer Reviewed
Volume 18
Pages 929-989
Keywords DNA damage and repair; Environmental sciences; Genomic instability; Predictive markers
Public URL
Additional Information This article has been published with separate supporting information. This supporting information has been incorporated into a single file on this repository and can be found at the end of the file associated with this output.