Fluorescent in situ hybridization (FISH) Fluorescent in situ hybridization (FISH) is a molecular cytogenetic technique that uses fluorescent probes that bind to only those parts of the chromosome with a high degree of sequence complementarity (analysis of chromosome structural aberrations) Used to identify the presence and location of a region of DNA or RNA within morphologically preserved chromosome preparations

Fluorescent in situ hybridization (FISH) This means you can view a segment or entire chromosome with your own eyes Was often used during M phase but is now used on I phase chromosomes as well

Fluorescent in situ hybridization (FISH) Advantage : 1) FISH is able to detect many small deletion , application and rearengment that are not visible with standard microscope analysis. 2) Diagnosis from FISH may avoid your child having to undergo many other test

Fluorescent in situ hybridization (FISH) Disadvantage : FISH testing doesn’t usually screen all chromosomes change

Fluorescent in situ hybridization (FISH) Probe: - Complementary sequences of target nucleic acid - Designed against the sequenced of interest - Probes are tagged with fluorescent dyes like Acridine orange, thiazol orange, propidium iodide (PI)

Fluorescent in situ hybridization (FISH) Application: - Use to detect and localize the present and absent of the specific DNA sequences on chromosome - FISH often used for finding specific features in DNA for use in genetic counseling medicine and species identification - FISH can also be used to detect and localize specific RNA target - Also used to detect circulating tumer cells.

Fluorescent in situ hybridization (FISH) Protocole : - Preparation of the fluorescent priobes - Denaturation of the probe and target - Hybridization of the probe and the target - Detection