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The comet assay: a method to measure DNA damage in individual cells

Nature Protocols volume 1, pages 23–29 (2006)Cite this article

Abstract

We present a procedure for the comet assay, a gel electrophoresis–based method that can be used to measure DNA damage in individual eukaryotic cells. It is versatile, relatively simple to perform and sensitive. Although most investigations make use of its ability to measure DNA single-strand breaks, modifications to the method allow detection of DNA double-strand breaks, cross-links, base damage and apoptotic nuclei. The limit of sensitivity is approximately 50 strand breaks per diploid mammalian cell. DNA damage and its repair in single-cell suspensions prepared from yeast, protozoa, plants, invertebrates and mammals can also be studied using this assay. Originally developed to measure variation in DNA damage and repair capacity within a population of mammalian cells, applications of the comet assay now range from human and sentinel animal biomonitoring (e.g., DNA damage in earthworms crawling through toxic waste sites) to measurement of DNA damage in specific genomic sequences. This protocol can be completed in fewer than 24 h.

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Figure 1: Typical dose response relationships for human cells exposed to ionizing radiation using the two methods described in this protocol.

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Acknowledgements

We thank R. Durand for developing the first comet analysis software.

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Authors and Affiliations

  1. British Columbia Cancer Research Center, 675 W. 10th Avenue, Vancouver, V5Z 1L3, British Columbia, Canada

    Peggy L Olive & Judit P Banáth

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  1. Peggy L Olive
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Correspondence to Peggy L Olive.

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Olive, P., Banáth, J. The comet assay: a method to measure DNA damage in individual cells. Nat Protoc 1, 23–29 (2006). https://doi.org/10.1038/nprot.2006.5

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