von Lindern M, Breems D, van Baal S, Adriaansen H, Grosveld G
Department of Cell Biology, Erasmus University, Rotterdam, The Netherlands.
Genes Chromosomes Cancer. 1992 Oct;5(3):227-34. doi: 10.1002/gcc.2870050309.
The t(6;9) associated with a subtype of acute myeloid leukemia (AML) was shown to generate a fusion between the 3' part of the CAN gene on chromosome 9 and the 5' part of the DEK gene on chromosome 6. The same part of the CAN gene appeared to be involved in a case of acute undifferentiated leukemia (AUL) as well, where it was fused to the SET gene. Genomic sequences around the translocation breakpoint were determined in two t(6;9) samples and in the case of the SET-CAN fusion. Although coexpression of myeloid markers and terminal deoxynucleotidyl transferase was shown to be one of the characteristics of t(6;9) AML, no addition of random nucleotides at the translocation breakpoint could be found. In addition, the breakpoint regions did not reveal heptamer-nonamer sequences, purine-pyrimidine tracts, a chi-octamer motif, or Alu repeats. The sequence in which the translocation breakpoints occurred was enriched in A/T. Notably, the specific introns in which clustering of breakpoints occurs in DEK and CAN both contain a LINE-I element. As LINE-I elements occur with a moderate frequency in the human genome, the presence of such an element in both breakpoint regions may be more than coincidental and may play a role in the translocation process.
与急性髓系白血病（AML）的一个亚型相关的t(6;9)被证明会导致9号染色体上CAN基因的3'部分与6号染色体上DEK基因的5'部分发生融合。CAN基因的同一部分似乎也参与了一例急性未分化白血病（AUL），在该病例中它与SET基因融合。在两个t(6;9)样本以及SET-CAN融合病例中确定了易位断点周围的基因组序列。虽然髓系标志物和末端脱氧核苷酸转移酶的共表达被证明是t(6;9) AML的特征之一，但在易位断点处未发现随机核苷酸的添加。此外，断点区域未显示七聚体-九聚体序列、嘌呤-嘧啶序列、chi-八聚体基序或Alu重复序列。易位断点发生的序列富含A/T。值得注意的是，DEK和CAN中发生断点聚集的特定内含子都包含一个LINE-1元件。由于LINE-1元件在人类基因组中出现的频率适中，两个断点区域都存在这样一个元件可能并非巧合，可能在易位过程中起作用。
