Fluorescence in-situ hybridisation (FISH) is a molecular cytogenetic technique used for the investigation of genes in specific chromosome regions. The technique binds a colour labelled DNA probe to a specific region on the patient chromosomes. As this is a targeted test it is important when requesting a FISH test to indicate the clinical condition that is being tested for.
At Genomic Diagnostics, FISH is used for the rapid diagnosis of suspected genetic syndromes such as Trisomy 21 (Down syndrome) and Turner Syndrome, or others listed below.
The technique can also be used for the gender determination in the presence of ambiguous genitalia. This test can determine mosaicism, and is usually performed in conjunction with conventional cytogenetic karyotype.
|1p36 microdeletion||1p telomere/1p36||FISH||Genes at 1p36|
|WOLF-HIRSCHHORN||4p16.3||FISH||Genes at 4p|
|Cri du Chat||5p15.2||FISH||EGR1|
|Prader Willi||15q11-q13||FISH||Genes at 15q11.2-q13|
|Angelman||15q11-q13||FISH||Genes at 15q11.2-q14|
|Di George/VCFS||22q11.2||FISH||Genes at 22q11.2|
|22q microdeletion syndrome||22q13.3||FISH||Genes at 22q13|
|Test||FISH for genetic syndromes|
|Genes||Targeted specific genes or chromosomes|
|Disease||Down syndrome features, ambiguous genitalia|
|Method||Dark field light microscope|
|Notes||Clinical notes indicating the condition that is being investigated is required. This test is performed in conjunction with a conventional or molecular karyotype.|
|Specimen||1-2mL Lithium heparin|
|Turn Around Time||1-2 working days|
|Required Documents||Physician Test Request Form|