Overview

Fluorescence in situ hybridization (FISH) is a type of hybridization in which a DNA "probe" is labeled with fluorescent molecules so that it can be seen with a microscope. The word "in situ" means that the hybridization occurs "in place", in this case, within the nucleus of specimen cells that have been fixed to a microscope slide.

To conduct a FISH analysis, one warms fixed cells mounted on a microscope slide to unwind their chromosomal DNA and allow access of the DNA probe. After adding the probe, the specimen cells are then cooled to allow the DNA probe to hybridize with its complementary target DNA. Once hybridized, the fluorescent molecules on the probe will show precisely where their target DNA lies along a chromosome. Depending upon the design of the probe DNA, one can detect many types of genetic changes.

The UroVysion Bladder Cancer Kit (UroVysion Kit) is designed to detect aneuploidy for chromosomes 3, 7, 17, and loss of the 9p21 locus via fluorescence in situ hybridization (FISH) in urine specimens from persons with hematuria suspected of having bladder cancer. Results from the UroVysion Kit are intended for use, in conjunction with and not in lieu of current standard diagnostic procedures, as an aid for initial diagnosis of bladder carcinoma in patients with hematuria and subsequent monitoring for tumor recurrence in patients previously diagnosed with bladder cancer.