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Trisomy 12 FISH

Test category:

Oncology - Leukaemia

Use of test


Trisomy of Chromosome 12 is the most common cytogenetic abnormality in patients with chronic lymphocytic leukaemia (CLL), and can be found in other mature B-cell neoplasms. This cytogenetic abnormality has prognostic implications.


The presence of trisomy 12 as a single abnormality is associated with a low risk of progression in CLL.

Ethical considerations:

This is an assay for non-heritable mutations. It does not raise issues of ethics or consent that are different from most other investigations ordered in the routine care of a patient.


Fluorescent in situ hybridisation (FISH) analysis, using probes specific to Chromosome 12.

Requesting the test


This test is usually requested by a haematologist or oncologist. In cases of CLL, it is usually requested as part of the CLL FISH panel.

Sample required:

0.5 mL bone marrow in transport media, or 5-10 mL blood in lithium heparin.

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.

Turnaround time:

2 business days.


Up to $255.

If more information is required, the requesting clinician can call our laboratory on (07) 3377 8573.


This test is not rebated by Medicare. The laboratory assumes that the patient or client has provided informed financial consent for the test.

Click here for our billing policy.