FISH procedures are the most commonly used for in situ hybridization. Using fluorescent markers to make DNA sequences more obvious make it much easier to assess the DNA strand and finding patterns for research.
For hybridization to occur, there must be hydrogen bonds that are created in order to hold the newly formed sequence. The probe will hybridize to its complementary sequence on the chromosome.
FISH is used in order to find the positions of genes on DNA, which is then used to figure out which genes show which characteristics. This was a very useful tool in the Human Genome Project, but now that it is complete FISH has been used to identify the location of genes on chromosomes. All of this has mostly been directed to clinical diagnoses.
Finding out why certain sections of DNA are replicated or even deleted has been crucial in unlocking the secrets of diseases and other issues. Many parents who are looking to have another child, after already having a child with developmental disabilities, can have a better informed decision, because they would then know if it was a random occurrence, or if their future children would have problems as well, or not.
Cancer is another leading area where FISH can be useful. Knowing the genetic makeup of those who have cancer or are at risk of cancer will be able to better receive a prognosis or diagnosis. Knowing whether a person is fully in remission will also become easier with the help of FISH.