A Neutral Glyoxal Gel Electrophoresis Method for the Detection and Semi-quantitation of DNA Single-Strand Breaks

  • Brian Pachkowski
  • Jun Nakamura
Part of the Methods in Molecular Biology book series (MIMB, volume 1054)


Single-strand breaks are among the most prevalent lesions found in DNA. Traditional electrophoretic methods (e.g., the Comet assay) used for investigating these lesions rely on alkaline conditions to denature DNA prior to electrophoresis. However, the presence of alkali-labile sites in DNA can result in the introduction of additional single-strand breaks upon alkali treatment during DNA sample processing. Herein, we describe a neutral glyoxal gel electrophoresis assay which is based on alkali-free DNA denaturation and is suitable for qualitative and semi-quantitative analyses of single-strand breaks in DNA isolated from different organisms.

Key words

Agarose Alkaline DNA damage DNA repair Electrophoresis Genotoxicant Glyoxal Neutral Single-strand breaks 



This work was supported in part by National Institute of Environmental Health Science grants (P42-ES05948, P30-ES10126).


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Copyright information

© Springer Science+Business Media, New York 2013

Authors and Affiliations

  • Brian Pachkowski
    • 1
  • Jun Nakamura
    • 1
  1. 1.Department of Environmental Sciences and EngineeringUniversity of North CarolinaChapel HillUSA

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