W I D COMMUNICATION The t(1;19)(q23;p13) Results in Consistent Fusion of E2A and PBXl Coding Sequences in Acute Lymphoblastic Leukemias

The t(1;19)(q23;p13) chromosomal translocation is observed cytogenetically in 25 % of children with pre-B-cell acute lymphoblastic leukemia (ALL) and is associated with an adverse treatment outcome. The t(1; 19) juxtaposes the E2A gene from chromosome 19 with the PBXl gene on chromo-some 1, leading to the production of fusion transcripts and resultant chimeric proteins that contain the transcriptional-activating motif of E2A and the DNA-binding homeodomain of PBX1. To investigate the molecular nature of E2AIPBXl fusion in patients with t(1;19) ALL we used an RNA-based polymerase chain reaction (PCR) procedure to amplify a portion of the chimeric transcript. We detected EZAIPBXI fusion transcripts in cells from 97 % (37 of 38) of cases in which the t(1; 19) had been observed cytogenetically. Molec-CUTE LYMPHOBLASTIC LEUKEMIA (ALL) is A frequently associated with clonal chromosomal rear