Comet Assay is a technique which can detect single-strand breaks as initial DNA damage.(1,2) Cells submitted to electrophoresis under alkaline conditions in low melting point agarose gel show DNA damage in a comet-like form when viewed at fluorescence microscopy. The lesion from each cell is quantified according to the comet tail length as class 0, 1, 2 or 3.(3) In sickle cell disease, due to constant oxidative stress and membrane lesions, this assay can be useful to detect DNA lesion intensity and medication response. Figure 1A illustrates cell nuclei from a 31-year-old sickle cell disease patient taking hydroxyurea classified as comet class 3. Figure 1B shows the result of a 33-year-old subject without any hemoglobinopathy where no lesions are observed.
Figure 1A/Figure 1B.
Electrophoresis under alkaline conditions in low melting point agarose gel of the cells of a sickle cell disease patient with damage classified as Comet class 3
Electrophoresis under alkaline conditions in low melting point agarose gel of the cells of a subject without any hemoglobinopathy and thus without DNA damage
Footnotes
Conflict-of-interest disclosure: The authors declare no competing financial interest
References
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