Specimen Collection
For specimen requirements please see:
Malignancy referrals
Postnatal referrals
Prenatal referrals
Note: FISH is performed on fixed cell preparations. Therefore, if a conventional G-band karyotype has been requested, no additional specimen is required.
Turnaround Time: 2 weeks, 4 days
Urgent cases: 5 days
Assay Method
FISH is a technique in which fluorescently labelled DNA probes are hybridised to target DNA on a slide. Interphase and/or metaphase cells are routinely analysed.
A wide variety of probes are available. Please see the probe list.
The number and quality of cells examined are based on the NPAAC guidelines, unless otherwise stated.
Limitations: FISH findings should never be used in isolation to establish a diagnosis. Any signal detected below the threshold is not reported. FISH studies target specific chromosome sequences, therefore the probes used in this study will only detect abnormalities at the loci specified.
Diagnostic Use and Interpretation
Fluorescence in situ hybridisation (FISH) is used for the rapid detection of specific chromosome abnormalities, some of which may be undetectable or difficult to characterise by conventional cytogenetic methods. FISH can be applied to a variety of specimen types, included cultured cell preparations as well as non-dividing interphase cells from uncultured preparations.
General uses for FISH include:
Postnatal referrals:
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Rapid aneuploidy testing e.g. ?trisomy 21
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Microdeletion syndromes
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Telomere probes to detect subtle translocations or deletions involving the ends of chromosomes.
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Marker chromosomes and other chromosome aberrations that are difficult to interpret by conventional cytogenetic techniques.
Note: All referrals received for aneuploidy screening and has a positive result, will have a subsequent G-banded karyotype with a report issued separately.
Prenatal referrals:
Malignancy referrals:
Used for the diagnosis and monitoring of haematological disorders and in the diagnosis of solid tumours. Its uses include:
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Detection of specific gene rearrangements that occur in different disorders
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Detection of copy number changes and gene amplifications
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Assessment of patients following sex-mismatched bone marrow transplantation
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Residual disease monitoring
Clinical details are essential so that the degree of urgency can be assessed and the most appropriate probe(s) can be applied.
Contact Information
To contact the Cytogenetics team:
Specimen Transport Instructions for Referring Laboratories
All samples must be collected using sterile technique
Same day delivery (>8 degrees Celsius to <24 degrees Celsius).