ZytoLight ® SPEC BCL2/IGH Dual Color Dual Fusion Probe

The ZytoLight ® SPEC BCL2/IGH Dual Color Dual Fusion Probe is designed to detect the translocation t(14;18)(q32.3;q21.3) affecting the BCL2 gene in the chromosomal region 18q21.33 and the IGH locus in 14q32.33. Translocations involving the BCL2 (B-cell lymphoma 2) gene and the IGH (immunoglobulin heavy locus, a.k.a. IGH@) gene are considered to be cytogenetic hallmarks for follicular lymphoma (FL). FL represents one of the most common non- Hodgkin lymphoma (NHL). About 75% of breakpoints on chromosome 18 are clustered in the major breakpoint region (MBR) and the minor cluster region (mcr), whereas the remaining breakpoints are scattered between these clusters, or at the 5’ side (variant cluster region or vcr) of the BCL2 gene. The translocation t(14;18)(q32.3;q21.3) has been identified in about 80% of FLs but is also observed in 20% to 30% of patients with diffuse large B-cell lymphoma (DLBCL). The rearrangement results in juxtaposition of the BCL2 gene at 18q21.33 next to the IgH (immunoglobulin heavy chain) locus at 14q32.33 and leads to overexpression of the anti-apoptotic protein BCL2. This represents most likely the initial step of malignant transformation, leading to suppression of apoptosis and progression to lymphoma. Detection of t(14;18) by Fluorescence in situ Hybridization (FISH) can be used to confirm the diagnosis of FL if histology is inconclusive. Additionally, this method can be used to monitor the response to therapy and detect recurrent disease.