Question
Asked 10 February 2015
Dhanasekar Krishnamoorthy
Dhanasekar Krishnamoorthy

What is the difference between Acridine orange assay and comet assay? how correlate the result?

i did acridine orange assay that result showed 99% of sperm no DNA damage but in comet assay more than 10% of Tail DNA observed, Why this much of variation and how to correlate? please explain me.
Acridine Orange
Comet Assay
DNA Damage
Sperm
Apoptosis Assays
Apoptosis

Most recent answer

Tapan A. Patel
University of Nebraska Medical Center
Actually both the assays are used to detect the DNA damage, but in acridine orange assay we do not have to electrophorese the so we can get the patches of staining in cell itself as well as cells remain intact. Whereas, in case of COMET assay we have to lyse the cells so the DNA content come out and then it is applied to electrophorese. As a result of applying electrohporesis technique in COMET the broken part of DNA showed long tailing, whereas in acridine orange assay it is not possible. 
You can correlate both assays, based on DNA damage you observed.
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All Answers (4)

Khushbu Jain
Government of India
Acridine orange assay is used to detect autophagy and this dye crosses into lysosomes. Comet assay is use to detect cellular DNA damage and any dye like DAPI, ethidium bromide can be use for comet assay. If you want to correlate cellular autophagic response with DNA damage you can use these two.
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Pradyumna Kumar Mishra
ICMR - National Institute for Research in Environmental Health, Bhopal, India
Please check the following link:
http://www.cometassayindia.org/protocols.htm
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Prem Rajak
Kazi Nazrul University
Acridine orange is used to detect apoptotic cells as it can easily penetrate into apoptotic cells causing a bright fluorescence. But, comet assay is specifically used for DNA damage. Generally level of DNA damage increases with the progression of apoptosis. 
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Tapan A. Patel
University of Nebraska Medical Center
Actually both the assays are used to detect the DNA damage, but in acridine orange assay we do not have to electrophorese the so we can get the patches of staining in cell itself as well as cells remain intact. Whereas, in case of COMET assay we have to lyse the cells so the DNA content come out and then it is applied to electrophorese. As a result of applying electrohporesis technique in COMET the broken part of DNA showed long tailing, whereas in acridine orange assay it is not possible. 
You can correlate both assays, based on DNA damage you observed.
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1 Recommendation

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