Fluorescence In Situ Hybridization (FISH) is a specialized laboratory test used to detect specific changes in chromosomes and genes. It uses fluorescently labelled DNA probes that attach to selected genetic regions, allowing specialists to identify missing, extra, rearranged, or amplified genetic material under a fluorescence microscope.
What Is the FISH Test Used For?
A FISH test can help investigate specific chromosomal abnormalities and genetic changes associated with certain cancers, blood disorders, developmental conditions, and other medical concerns. Depending on the clinical requirement, FISH may be performed on blood, bone marrow, tissue, or other appropriate samples.
In cancer diagnosis, FISH testing may be used to look for gene amplifications, deletions, translocations, or other chromosome changes that can support diagnosis and treatment planning. The exact FISH probes selected depend on the suspected condition and the clinical question.
Before the Test
Preparation depends on the sample required and the reason for testing. Your doctor or laboratory will explain the appropriate sample collection procedure and any specific instructions. Test interpretation should always be considered alongside clinical history and other laboratory findings.