What is the cost of FISH Test in India

FISH:

FISH Test (Fluorescence in situ hybridization) is a test that "maps" the genetic material in human cells, including specific genes or portions of genes. Because a FISH test can detect genetic abnormalities associated with cancer, it's useful for diagnosing some types of the disease.

FISH testing is done on breast cancer tissue removed during biopsy to see if the cells have extra copies of the HER2 gene. The FISH test results will tell you that the cancer is either “positive” or “negative” (a result sometimes reported as “zero”) for HER2. 

FISH can find most chromosome changes (such as deletions or translocations) that can be seen under a microscope in standard cytogenetic tests, as well as some changes too small to be seen with usual cytogenetic testing. 

It can detect genetic abnormalities--specifically for cancer. It is used to diagnose certain types of cancer, and can somewhat predict a patient's outcome and susceptibility to chemotherapy treatment.

What is FISH used for?  

Scientists use three different types of FISH probes, each of which has a different application: 

• Locus specific probes bind to a particular region of a chromosome. This type of probe is useful when scientists have isolated a small portion of a gene and want to determine on which chromosome the gene is located, or how many copies of a gene exist within a particular genome. 
• Alphoid or centromeric repeat probes are generated from repetitive sequences found in the middle of each chromosome. Researchers use these probes to determine whether an individual has the correct number of chromosomes. These probes can also be used in combination with "locus-specific probes" to determine whether an individual is missing genetic material from a particular chromosome. 
• Whole chromosome probes are actually collections of smaller probes, each of which binds to a different sequence along the length of a given chromosome. Using multiple probes labelled with a mixture of different fluorescent dyes, scientists are able to label each chromosome in its own unique colour. 

What is the cost of the FISH Test?

The cost of the FISH Test ranges from Rs.6000 to Rs.22000

How does FISH work?

FISH is useful, for example, to help a researcher or clinician identify where a particular gene falls within an individual's chromosomes. 

1. The first step is to prepare short sequences of single-stranded DNA that match a portion of the gene the researcher is looking for. These are called probes. 
2. The next step is to label these probes by attaching one of a number of colours of fluorescent dye.DNA is composed of two strands of complementary molecules that bind to each other like chemical magnets. 
3. Since the researchers' probes are single-stranded, they are able to bind to the complementary strand of DNA, wherever it may reside on a person's chromosomes. When a probe binds to a chromosome, its fluorescent tag provides a way for researchers to see its location. 

FISH Testing in Cancer:

 FISH is a technique that uses fluorescent probes to detect specific genes or parts of genes (DNA sequences). Medical centre lab personnel and oncologists use FISH to help assess patients who may have cancer, and sometimes to monitor a patient who has already been diagnosed with cancer and treated. 

FISH can be done using various types of samples according to the location and the type of cancer suspected. Tumour cells are obtained from peripheral blood, from a bone marrow biopsy or from a lymph node biopsy, and formalin-fixed paraffin-embedded tissue.

What conditions does this test look for?

Unlike prenatal screening tests which only look for genetic changes involving a small number of our chromosomes, prenatal diagnostic investigations using chromosome microarray assess all 23 chromosome pairs. 

This means diagnostic testing provides a more detailed investigation for chromosomal causes of growth and developmental concerns detected during pregnancy.

What do the test results mean?

This test can show the presence of abnormal or immature cells, which may indicate an underlying condition, provide information about its severity and suggest the need for further testing. Abnormal patterns of white cells may point to infections, leukaemia, immune disorders, inflammation and other problems.