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 JH 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.