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 for selected products have been updated. These updates ensure a consistent presentation of all gaps larger than 10 kb including adjustments to markers, genes, and related elements. This update does not affect the device characteristics or product composition. Please refer to the list to find out which products now include updated probe maps.

Probe map details are based on UCSC Genome Browser GRCh37/hg19, with map components not to scale.

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