Translocations involving the E2A (TCF3: Transcription Factor 3) gene are some of the most common rearrangements in childhood B-ALL, specifically B-cell precursor ALL1.
The two main partner genes are PBX1 and HLF (on chromosomes 1 and 17 respectively) which become fused to E2A as a result of the t(1;19) and t(17;19) translocations, forming the E2A/PBX1 and E2A/HLF fusion proteins. Other translocation partners have also been detected.
The t(1;19) is the most common E2A rearrangement, being present in around 5% of B-ALL and 20% of pre B-ALL2, whilst the t(17;19) is present in around 1% of all ALL cases3. Both are historically associated with a poor outcome, though treatment therapies have overcome this in the case of the t(1;19)4. Detection of the t(1;19) is best carried out using molecular methods, such as FISH, as the fusion has been shown to be missed in 20 to 25% of patients by standard cytogenetics5. Similarly, other E2A translocations have been shown to be cytogenetically cryptic6.
The quality of the products we have received from Cytocell have been excellent. The FISH probes they provide to us give intense, strong signals and are a pleasure to count. What has really stood out however has been the level of support and assistance provided by Cytocell’s application specialists. The team worked very closely alongside our own during the adoption of this product and spent many hours with us perfecting the technique, going above and beyond what I would expect during the transition period. Source BioScience absolutely demand high quality products and service to be able to deliver our results with confidence, and that is what we have received from Cytocell. Neil Ryan, Laboratory Operations Manager at Source BioScience
1. Barber et al., Genes Chromosomes Cancer. 2007 May;46(5):478-86
2. Alonso CN. t(1;19)(q23;p13) TCF3/PBX1. Atlas Genet Cytogenet Oncol Haematol. July 2012
3. Viguié F . t(17;19)(q22;p13). Atlas Genet Cytogenet Oncol Haematol. May 1999
4. Felice et al., Leuk Lymphoma. 2011 Jul;52(7):1215-21
5. Izraeli et al., Leukemia 1993;7(5):671-8
6. Huret JL. TCF3 (transcription factor 3 (E2A immunoglobulin enhancer binding factors E12/E47)). Atlas GenetCytogenet Oncol Haematol. January 2012