Molecular Detection of t(14;18)(q32;q21) in Follicular Lymphoma

The t(14;18)(q32;q21) can be detected in approximately 80% of cases of follicular lymphoma (FL). This translocation juxtaposes the BCL2 oncogene at 18q21 with the IGH@ at 14q32, and leads to overexpression of BCL2 protein which protects the cells from apoptosis. The high degree of sequence homology among the 3′ portion of the J_H segments and the clustering of breakpoints on chromosome 18 make the IGH@/BCL2 very amenable to polymerase chain reaction (PCR) detection. We describe two multiplex TaqMan-based real-time PCR assays which can be used to detect and quantify the major and minor breatpoint cluster regions of IGH@/BCL2 fusion products in newly diagnosed FL, and to monitor minimal residual disease during treatment or early relapse.