The AML1 probe mix consists of a 156kb probe, labelled in red, centromeric to the AML1 (RUNX1) gene that spans the CLIC6 gene and a 169kb probe, labelled in green, covering part of the AML1 (RUNX1) gene, including markers SHGC-87606 and D21S1921.
The RUNX1 (RUNX family transcription factor 1) gene at 21q22.1 is one of the most frequent targets of chromosomal rearrangements observed in human acute leukaemia.
The most common rearrangements are the ETV6::RUNX1 and RUNX1::RUNX1T1 fusions. The ETV6::RUNX1 fusion is brought about by the t(12;21)(p13.2;q22.1) translocation, observed in around 21% of childhood B-cell acute lymphoblastic leukaemia (ALL) cases1, whilst the RUNX1::RUNX1T1 fusion is the result of the t(8;21)(q21.3;q22.1) translocation observed in 10-22% of patients with acute myeloid leukaemia (AML) FAB (French-American-British classification) type M2 and 5-10% of AML cases overall2,3. Both these rearrangements are considered good prognostic indicators in these diseases4,5.
The RUNX1 gene is also rearranged in many other rarer translocations, with partners including chromosomes 1, 2, 3, 4, 5, 6, 7, 9, 10, 14, 15, 16, 17, 18, 19, 20 and X6. This breakapart probe has been designed to allow the detection of rearrangements regardless of the partner gene.
The CytoCell® AML1 (RUNX1) Breakapart Probe is a qualitative, non-automated, fluorescence in situ hybridisation (FISH) test used to detect chromosomal rearrangements in the 21q22.1 region on chromosome 21 in Carnoy’s solution (3:1 methanol/acetic acid) fixed haematologically-derived cell suspensions from patients with confirmed or suspected acute myeloid leukaemia (AML) or acute lymphoblastic leukaemia (ALL).
This device is designed as an adjunct to other clinical and histopathological tests in recognised diagnostic and clinical care pathways, where knowledge of AML1 (RUNX1) rearrangement status would be important for clinical management.
This device is designed to detect rearrangements with breakpoints in the region bounded by the red and green clones in this probe set, which includes the AML1 (RUNX1) region. Breakpoints outside this region or variant rearrangements wholly contained within this region may not be detected with this device. Due to the scattered breakpoint region, in some rearrangements in acute lymphoblastic leukaemia (ALL) users may observe variant signal patterns.
This device is not intended for: use as a stand-alone diagnostic, use as a companion diagnostic, prenatal testing, population-based screening, near-patient testing, or self-testing.
This device has not been validated for sample types, disease types, or purposes outside of those stated in the intended purpose.
It is intended as an adjunct to other diagnostic laboratory tests and therapeutic action should not be initiated on the basis of the FISH result alone.
Reporting and interpretation of FISH results should be performed by suitably qualified staff, consistent with professional standards of practice, and should take into consideration other relevant test results, clinical and diagnostic information.
This device is intended for laboratory professional use only.
Failure to adhere to the protocol may affect the performance and lead to false positive/negative results.
We have been working with CytoCell fish probes for 2 decades because of their excellent clarity and intensity regardless of the size of the probe. It is so clear and simple to detect. The available probes are created as a best solution for detection of most frequent rearrangements in routine diagnostic and has high hybridization rate. Also, we are very pleased with the choice of probes that perfectly meets the needs of our laboratory. Special impression left the fact that technical support is provided by the people who worked in the laboratory and who are close to the problems we face, so they have the appropriate solution.
Dr Marina Djurisic
Head of Laboratory of Medical Genetics, Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Belgrade, Serbia