Definition of Fluorescence In Situ Hybridization

Fluorescence in situ hybridization (FISH) is a form of in situ hybridization in which the probe (DNA) is labelled with a fluorescent material. In situ hybridization (ISH) is defined as a technique that is used in order to map the location of the genes and other sequences of DNA that are present in the chromosomes of the large eukaryotic organisms. A probe i.e. DNA or RNA is also used in this method which is complementary to the DNA sequence.

The purpose of this probe is to detect the location of the gene in the chromosome. The location of the gene can help us in the understanding of the organization, regulation and functions of the genes. DNA ISH is used in the determination of the chromosomal structure. Fluorescent DNA ISH is used to assess the integrity of chromosomes in medical diagnostics.