in situ hybridization

Last reviewed 01/2018

The principle of in situ hybridization is to use labelled DNA or RNA from the gene of interest to identify a matching segment within the genome. This may be shown as a separate position on a chromosome or, as a marked area within an individual cell or region within a tissue.

The gene's DNA may be synthesised by complimentary DNA cloning from messenger RNA or by isolation of the DNA from a chromosome specific library. The DNA is rendered into a single strand before being radiolabelled and then added to a standard chromosome preparation.

The complimentary DNA sequence is revealed by autoradiography or fluorescent imaging.