Fluoreszence-in-situ-Hybridisation (FISH)

Allgemeines

In fluorescence-in-situ-hybridisation (FISH) analysis fluorochrome labelled sequences of DNA are hybridised to metaphase chromosomes or interphase nuclei.

 

Microdeletion FISH analysis

Microdeletions are very small chromosomal deletions (< 3Mb) which are not detectable when a standard karyotyping is performed.

Probes specific for known microdeletions detect these small deletions in a fluorescence-in-situ-hybridisation (FISH) analysis.

 

Subtelomeric FISH analysis

The subtelomeric regions of the chromosomes are gene rich DNA sequences close to the ends (telomeres) of the chromosomes. Fluorescence-in-situ-Hybridisation (FISH-Analysis) revealed small cryptic chromosomal imbalances in patients with mental retardation, especially in alliance with delevopmental retardation and dysmorphic signs not detectable with standard karyotyping.

 

Aneuploidy screening

This prenatal FISH-analysis with specific DNA-probes for chromosomes which are amongst others responsible for the majority of trisomies delivers a result for the number of chromosomes 13, 18, 21, X and Y within 24 hours.

 

Chromosome painting

Whole chromosome paint (WCP, chromosome paint probes) or chromosome arm specific (PCP, partial chromosome paint) detect larger chromosomal aberrations and marker chromosomes not identifiable with standard staining techniques.

 

Multiplex-Fluoreszence-in-situ-Hybridisation (M-FISH)

M-FISH is a special FISH application with combinatorial labelled chromsome spezific libraries of all 24 human chromosomes. It allows the identification of chromosomal aberrations which can not be characterised using standard karyotyping or staining techniques.

 

Diagnostik