Use of test
Chromosomal abnormalities resulting in deletion at 7q or monosomy 7 can occur in both acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS). Genes in the deleted region include EPO, PLANH1 and MET. Deletions at 7q are also common in therapy-related AML/MDS. These abnormalities have prognostic implications.
Monosomy 7q is an indicator of poor prognosis, often occurring in association with other cytogenetic abnormalities.
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 within the region of 7q commonly deleted in AML/MDS. This interphase FISH test has a cut off at 5%. A low level of positive cells may be due to overlap of the two signals. Studies of normal controls indicate that this level is less than 5%. Small abnormal populations may therefore not be detectable.
Requesting the test
0.5 mL bone marrow in transport media (or 10 mL blood in lithium heparin if blasts >10%).
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.
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.