Our Tests

Rapid Interphase FISH

Also known as: Urgent Neonate Karyotype with Rapid FISH

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Chromosome analysis can detect balanced and unbalanced rearrangements, and numerical changes of autosomes and sex chromosomes. The identification of such abnormalities provides diagnostic and prognostic information.

This test involves rapid assessment of the number of selected chromosomes followed by rapid assessment of the structure and number of all chromosomes.

Clinical Utility

In an affected baby, an abnormal result usually provides a genetic diagnosis and the basis for genetic counselling. A normal result does not exclude a genetic or heritable basis for the disorder.

This is an assay for heritable mutations. It may raise issues of ethics or consent that are different from most other investigations ordered in the routine care of a patient. The interpretation of the result may also be dependent on the family history and the interpretation of other studies.


Not specified

Test Method

Analysis of the number of selected chromosomes by fluorescent in situ hybridisation (FISH) followed by analysis of all metaphase chromosomes by light microscopy.

Test Ordering

This test is usually requested by a paediatrician or clinical geneticist.

1-5 mL blood in lithium heparin. Specimens may be collected by the requesting practitioner.

To help ensure the quality of the test, a genetic test should be done with a dedicated sample whenever possible i.e. a sample collected specifically for that test rather than a sample that is used for multiple tests.

We also recommend that the patient or another adult check the labelling of request forms and sample tubes.

Special Instructions

Please include details of any clinical abnormalities in the patient being tested, and the results of chromosome studies in relatives.


$205 - $394.55

The price varies according to the specific clinical conditions for a particular patient. Please contact Sonic Genetics on 1800 010 447 for more information.

Medicare Rebate

This test has a Medicare rebate of $305.15, subject to the requirements of the Medicare descriptor being met. The MBS item number is 73291.

Turnaround Time

24 hours for a FISH result; 3 days for the chromosome analysis