Use of test
Chromosome analysis can detect balanced rearrangements and numerical changes of sex chromosomes that can be the cause of reproductive disorders. Chromosome studies of the patient's partner may be necessary to clarify the genetic diagnosis and the risks to relatives.
In an affected person, 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 as submicroscopic changes would not be detected.
This assay may identify a heritable mutation and hence raise issues of ethics or consent that are different from most other investigations ordered in the routine care of a patient.
Analysis of metaphase chromosomes by light microscopy. Chromosomes are counted, and examined for structural and numerical abnormalities.
Requesting the test
This test can be requested by any medical practitioner.
2-5 mL blood in EDTA. Specimens may be collected by the requesting practitioner or at any Sonic Healthcare collection centre (see link below).
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 recommend that the patient or another adult check the labelling of request forms and sample tubes.
6-12 weeks. Please enquire with the laboratory for any clinically urgent results.
This test has a Medicare rebate which, subject to the requirements of the Medicare descriptor being met, may cover all or part of the cost. If the patient is not eligible for rebated testing, please contact your local Sonic pathology practice for pricing.
The Medicare details, including descriptor and schedule fee, are listed under MBS item 73289.