What can fluorescent in situ hybridization detect?

What can fluorescent in situ hybridization detect?

Today, most in situ hybridization procedures use fluorescent probes to detect DNA sequences, and the process is commonly referred to as FISH (fluorescence in situ hybridization). A variety of FISH procedures are available to cytogeneticists, who use them to diagnose many types of chromosomal abnormalities in patients.

How do you read FISH results?

How your doctor interprets this test is as follows:

1. A result of 0 is negative.
2. A result of 1+ is also negative.
3. A result of 2+ is considered equivocal (uncertain).
4. A result of 3+ is positive.

How does FISH analysis work?

Fluorescence in situ hybridization (FISH) is a laboratory technique for detecting and locating a specific DNA sequence on a chromosome. The technique relies on exposing chromosomes to a small DNA sequence called a probe that has a fluorescent molecule attached to it.

What is the resolution of FISH?

The analytical resolution of FISH is in the range of 100–200 Kb as determined by the probe size, which is 50-fold higher than the 5–10 megabase (Mb) Giesma banding of a high resolution karyotyping.

How accurate is FISH test?

Accuracy and limitations. Prenatal interphase FISH testing is highly accurate, with reported false-positive and -negative rates usually less than 1%. The main problem, however, is that not all specimens are informative. Uninformative rates will vary among laboratories, but rates of 3% to 10% are considered typical.

Can FISH results be wrong?

In general FISH for five chromosomes does not rule out numerical aberrations of all other chromosomes, structural aberrations, and sSMCs. False-positive respectively false negative results are also possible due to dicentric chromosomes, centromeric polymorphism, and maternal contamination [13].

What is a positive FISH test?

FISH testing usually returns one of two results: positive or negative. Positive means your breast cancer cells make too much HER2 and your doctor should treat you with drugs that target that protein. Negative means the protein isn’t involved in the growth of your tumor.

What is in situ hybridization?

is a technique that allows for precise localization of a specific segment of nucleic acid within a histologic section.

When is in situ hybridization used?

In situ hybridization is a technique that is used for localization and detection of specific DNA and RNA sequences in cells, preserved tissue sections, or entire tissue (whole mount in situ hybridization, Fig. 1) by hybridizing the complementary strand of a nucleotide probe to a particular sequence.

How do you detect situ hybridization?

In situ hybridization indicates the localization of gene expression in their cellular environment. A labeled RNA or DNA probe can be used to hybridize to a known target mRNA or DNA sequence within a sample. This labeled RNA or DNA probe can then be detected by using an antibody to detect the label on the probe.