Molecular cloning of a 5' segment of the genomic phl gene defines a new breakpoint cluster region (bcr2) in Philadelphia-positive acute leukemias.
Molecular cloning of a 5' segment of the genomic phl gene defines a new breakpoint cluster region (bcr2) in Philadelphia-positive acute leukemias.
复制标题
基因组 phl 基因 5 片段的分子克隆在费城阳性急性白血病中定义了一个新的断点簇区域 (bcr2)。
作者：
Saijuan Chen;Zhu Chen;J. D. Grausz;J. Hillion;Luc d'Auriol;G. Flandrin;Christian;Roland Berger
Ph 1染色体的分子重排是CML的标志，聚集在一个5.8 kb的DNA片段中，即位于染色体22 q11的phl基因的所谓断点簇区（bcr）。在Ph 1阳性（Ph 1+）ALL中，重排涉及5.8-kb bcr（称为bcr+）或phl基因5'端bcr上游区域（bcr-）。为了深入了解Ph 1+急性白血病中发生的重排，分析了来自ph 1 5'端的64-kb DNA片段，以产生覆盖ph 1基因第一内含子的40 kb的分子探针。一组7例bcr-Ph 1+急性白血病（3例非淋巴细胞和4例淋巴细胞）进行了研究，这些内含子1衍生的探针。引人注目的是，在7例白血病中的6例中，断点位于10.8 kb的DNA片段中，定义了一种新的bcr，似乎对Ph 1+急性白血病具有特异性。与位于phl基因3'端的CML bcr区类似，我们建议将这一10.8 kb片段命名为bcr 2。
Molecular rearrangements of Ph1 chromosome, the hallmark of CML, are clustered in a 5.8-kb DNA segment, the so-called breakpoint cluster region (bcr) of the phl gene that is localized to chromosome 22q11. In Ph1-positive (Ph1+) ALLs, the rearrangements have been shown to involve either the 5.8-kb bcr (called bcr+) or a region upstream of bcr in the 5' end of the phl gene (bcr-). To gain insight into the rearrangements occurring in Ph1+ acute leukemias, a 64-kb DNA fragment from the 5' end of phl was analyzed in order to generate molecular probes covering 40 kb of the phl gene first intron. A panel of seven cases of bcr-Ph1+ acute leukemia (three nonlymphocytic and four lymphocytic) was investigated with these intron 1-derived probes. Strikingly, in six of the seven leukemias, the breakpoints were located in a 10.8-kb DNA segment, defining a new bcr which appears to be specific for Ph1+ acute leukemias. By analogy with the CML bcr region located in the 3' part of the phl gene, we propose to designate this 10.8-kb fragment bcr2.