Identification of a transcriptional unit adjacent to the breakpoint in the 14;19 translocation of chronic lymphocytic leukemia

✍ Scribed by Timothy W. McKeithan; Hitoshi Ohno; Manuel O. Diaz

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 829 KB
• Volume: 1
• Category: Article
• ISSN: 1045-2257
• DOI: 10.1002/gcc.2870010310

✦ Synopsis

The t( 14; 19)(q32.3;q I 3. I ) is a recurring translocation found in the neoplastic cells of some patients with chronic lymphocytic leukemia (CLL). W e have previously cloned the translocation breakpoint junction present in the leukemic cells from one such patient. In the present study, we have cloned and sequenced the breakpoint junction from a second patient. The breakpoint on chromosome 14 occurs within a switch region upstream of the immunoglobulin heavy chain Cal sequence. W e detected a 2.1-2.3 kb transcript on Northern blots using a probe from chromosome I 9 adjacent to this breakpoint. S, nuclease protection experiments showed that transcription of the gene proceeds in a direction away from the breakpoint junction. This gene (for which we propose the name BCL3) may contribute to the malignant development of B-lymphocytes following the chromosome translocation. If so, it is the first protooncogene identified whose activation is principally associated with CLL.