XL CUX1/EZH2/7cen consists of an orange-labeled probe hybridizing to the CUX1 gene region at 7q22, a green-labeled probe hybridizing to the EZH2 gene region at 7q36 and an aqua-labeled probe hybridizing to the centromere of chromosome 7.

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.

Partial deletions of the long arm of chromosome 7 [del(7q),7q-] or monosomy 7 (-7) are highly recurrent chromosomal aberrations frequently observed in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In MDS and AML, del(7q) as sole cytogenetic aberration has a prevalence of less than 5%. However, many of the examined patients with del(7q) have additional cytogenetic aberrations. Furthermore, whole-exome sequencing studies analyzed the coincidence of mutated genes (e.g. CUX1, LUCL2, CUL1, and EZH2) and -7 or del(7q).
7q deletions are assigned to the intermediate genetic prognostic risk group (ELN risk stratification) or the high risk prognostic group (revised MRC classification), in AML. However, 7q- are classified by the revised IPSS (International prognostic scoring system) as 'intermediate cytogenetic prognostic risk' or 'poor risk' - if coincide with another abnormality, in MDS.
Several deleted regions have been identified along the long arm of chromosome 7, but two critical genomic regions are known to be commonly deleted regions (CDRs): 7q22 and 7q31-q36. Studies focusing on CDRs on 7q have highlighted the significance of the gene loci of EZH2, SAMD9L, CUX1, MLL3, and DOCK4, whose assumed roles as tumor suppressor genes could explain the criticality of their haploinsufficiency.
The CUX1 gene locus has been described as frequently deleted locus in case of 7q deletions, increasing the accuracy of the diagnosis of 7q22 deletions.

Clinical Applications

• Acute Myelogenous Leukemia (AML)
• Myelodysplastic Syndrome (MDS)

XL CUX1/EZH2/7cen hybridized to lymphocytes. One normal interphase and one normal metaphase are shown.

• Le Beau et al (1996) Blood 88:1930-1935
• Struski and Luquet (2019) Ann Biol Clin (Paris) 77:229-230
• Hartmann et al (2019) Genes Chromosomes Cancer 58:698-704