This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Gu, Y. Articles by Canaani, E. Search for Related Content PubMed Articles by Gu, Y. Articles by Canaani, E.

Sequence Analysis of the Breakpoint Cluster Region in the ALL-1 Gene Involved in Acute Leukemia¹

Jefferson Cancer Institute, Jefferson Cancer Center, and Department of Microbiology and Immunology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania 19107

DNA rearrangements caused by chromosome translocations between band 11q23 and various chromosomes can be detected by a single probe, B859, an 859-base pair complementary DNA fragment derived from the human ALL-1 gene. To try to understand why band 11q23 becomes a frequent target of the translocations, we have sequenced the entire breakpoint cluster region, a 8342-base pair BamHI genomic fragment delineated by B859. We found eight Alu repeats located within this region in the same orientation as the ALL-1 gene. We have also analyzed the sequences of the breakpoints in 10 patients with 6 different types of 11q23 aberration. In five patients the breaks coincided with Alu sequences on chromosome 11, but not on the partner chromosomes. Also, seven of the breaks occurred in the region delineated by exons 6 and 7, which is composed mainly of Alu sequences. In three patients topoisomerase II recognition site-like sequences, at different stringency levels, were identified at the breakpoints on chromosome 11. We conclude that while there is no specific sequence element present at all the breakpoints, the high density of Alu sequences in the breakpoint cluster region possibly makes the latter more prone to recombination events.

¹ Supported by grants from the National Cancer Institute and the American Cancer Society.

² To whom requests for reprints should be addressed, at Jefferson Cancer Institute, Jefferson Medical College, BLSB, Room 1050, 233 South 10th Street, Philadelphia, PA 19107-5799.

³ Present address: Weizman Institute of Science, Rehovot, Israel 76100.

Received 3/ 3/94. Accepted 3/21/94.