XL IRF4 BA consists of a green-labeled probe hybridizing proximal to the IRF4 gene region at 6p25 and an orange-labeled probe hybridizing distal to the IRF4 gene region at 6p25.

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.

The updated (2016) revision of the World Health Organization (WHO) classification of tumors of lymphoid neoplasms considers the large B-cell lymphoma with IRF4 rearrangement as a new provisional entity. Head and neck regions including the Waldeyer ring are particularly affected. Chromosomal translocations involving the IRF4 gene and the immunoglobulin loci IGH, IGL and IGK (IG) result in dysregulation of IRF4 expression; other translocation partners may occur. Since t(6;14)(p25;q32) is cytogenetically cryptic, FISH is a valuable tool in detecting this recurrent aberration. IG/IRF4 positive lymphomas normally lack t(14;18), which is observed in about 85% of adult patients with follicular lymphoma, and are commonly associated with young age and a good course. IRF4 rearrangements have also been identified in peripheral T-cell lymphomas (PTCL). PTCL are defined as a diverse group of aggressive lymphomas of mature-stage T-cells accounting for about 10% of non-Hodgkin lymphomas. Recent data suggests that IRF4 translocations detected by FISH have a predictive value for primary cutaneous CD30(+) anaplastic large cell lymphoma.

Clinical Applications

• Non-Hodgkin Lymphomas (NHL)

XL IRF4 BA hybridized to lymphozytes. One aberrant cell with split signal is shown, indicating a break in the IRF4 locus. Additionally, one normal interphase is shown.

• Feldman et al (2009) Leukemia 23:574-580
• Salaverria et al (2011) Blood 7:139-147
• Kiran et al (2013) Leukemia Research 37:396-400

• Utility and performance of bacterial artificial chromosomes-on-beads assays in chromosome analysis of clinical prenatal samples, products of conception and blood samples.
• A child with multiple congenital anomalies due to partial trisomy 7q22.1 → qter resulting from a maternally inherited balanced translocation: a case report and review of literature.
• Distinct roles of ATM and ATR in the regulation of ARP8 phosphorylation to prevent chromosome translocations.
• Heterogeneous MYCN amplification in neuroblastoma: a SIOP Europe Neuroblastoma Study.
• Immense random colocalization, revealed by automated high content image cytometry, seriously questions FISH as gold standard for detecting EML4-ALK fusion.
• Fluorescence in situ hybridisation assays designed for del(7q) detection uncover more complex rearrangements in myeloid leukaemia cell lines
• Detection of t(7;12)(q36;p13) in paediatric leukaemia using dual colour fluorescence in situ hybridisation.
• A rare case of t(11;22) in a mantle cell lymphoma like B-cell neoplasiaresulting in a fusion of IGL and CCND1: case report.
• Genomic DNA-chip hybridization in t(11;14)-positive mantle cell lymphomas shows a high frequency of aberrations and allows a refined characterization of consensus regions.