XL t(8;21) plus consists of a green-labeled probe hybridizing to the RUNX1T1 gene region at 8q21.3-22.1 and an orange-labeled probe hybridizing to the RUNX1 gene region at 21q22.1.

Probe maps are created in accordance with the intended purpose of the product. Solid colored bars do not necessarily indicate that the probe fully covers the indicated genomic region. Therefore, caution is advised when interpreting results generated through off-label use. Probe map details based on UCSC Genome Browser GRCh37/hg19. Map components not to scale. Further information is available on request.

Several recurrent balanced translocations and inversions, and their variants, are recognized in the WHO category acute myeloid leukemia (AML) with recurrent genetic abnormalities. Furthermore, several cytogenetic abnormalities are considered sufficient to establish the WHO diagnosis of AML with myelodysplasia-related features if 20% or more blood or marrow blasts are present.

t(8;21)(q21;q22) is the most common translocation in de novo AML occurring in up to 20% of adult and 40% of pediatric cases. The translocation fuses RUNX1 with RUNX1T1 to produce a RUNX1/RUNX1T1 fusion gene located on the derivative chromosome 8. For these patients, the prognosis after intensive chemotherapy is better than for the majority of AML patients. Small hidden interstitial insertions resulting in a RUNX1/RUNX1T1 rearrangement have been found, necessitating the use of a breakpoint spanning rather than a breakpoint flanking FISH probe.

Clinical Applications

• Acute Myelogenous Leukemia (AML)

XL t(8;21) plus hybridized to lymphocytes. One normal metaphase and one normal interphase are shown.

• Zhang et al (2002) PNAS 99:3070-3075
• Gamerdinger et al (2003) Gene Chromosome Canc 36:261-272
• Jang et al (2010) Ann Clin Lab Sci 40:80-84