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In Situ Hybridization

Controlling The Specificity Of The Cytochemical Assays

Good cytochemists know that experimental results must be checked and verified. For this reason, in addition to testing for reactions with their target DNA or RNA, they also test for reactions with unrelated nucleotide sequences. Likewise, they test for reactions with other components of the detection systems.

There are a series of controls that are run that detect if the labeling pattern is due to the proper sequence of reactants. For example, if the cyto-chemist leaves out the probe in the hybridization solution, there should be no reaction. Similarly, if the cytochemist changes the sequence of the probe, or uses a noncomplementary probe, there should be no reaction (unless that new sequences reacts with another sequence in the cell). Tests of the detection system must also be run by leaving out one or more components to learn if the reaction is dependent totally on the complete sequence of reactants.


Gwen V. Childs


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Additional topics

Medicine EncyclopediaGenetics in Medicine - Part 2In Situ Hybridization - Application Of The Probe For Dna Or Rna To Tissues Or Cells, Conditions That Promote Optimal In Situ Hybridization