BCL2/IGH dual-color double fusion probe is designed to detect the translocation of t(14;18)(q32.3;q21.3), that is, the IGH gene at chromosome 14q32.33 and the BCL2 gene at 18q21.33 region. The translocation of the IGH (immune sphere gene) and BCL2 (B cell lymphoma) gene involved is a cytogenetic marker of FL (follicular lymphoma). FL is one of the most common NHL (non-Hodgkin’s lymphoma). The t(14;18)(q32.3;q21.3) translocation is present in approximately 80% of patients with follicular lymphoma, but it is also found in 20% to 30% of diffuse large B-cell lymphoma (DLBCL) patients. If histology is uncertain, fluorescence in situ hybridization (FISH) can be used to detect t(14;18).
BCL2 orange probe labeled with an orange-red fluorescent dye and IGH green probe labeled with a green fluorescent dye bound to the target detection site by in situ hybridization. Under normal conditions (BCL2/IGH gene is not fused), it shows two orange-red signals and two green signals under a fluorescence microscope. When there is gene fusion, the green and orange-red signals form a yellow fusion signal due to recombination.
The t(14;18) translocation occurs in 85% of follicular lymphoma (FL) and 1/3 of diffuse lymphoma (DL) with a poor prognosis. Studies have shown that BCL2/IGH translocation rearrangement plays a role in stimulating B lymphocyte hyper proliferation. The incidence of most translocations in patients with non-Hodgkin’s lymphoma is significantly higher than that in healthy controls.
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