title: Ph-negative chronic myeloid leukemia: molecular analysis of ABL insertion into M-BCR on chromosome 22.
abstract: Leukemic cells from a patient with Ph-negative chronic myeloid leukemia (CML) had a normal karyotype. M-BCR was rearranged and chromosome in situ hybridization showed an ABL insertion between 5' and 3' M-BCR on an apparently normal chromosome 22. The association of 5' BCR and 3' ABL at the 5' junction of the chromosome 9 insert was typical of that found for the BCR-ABL fusion gene in other patients with the standard t(9;22) and CML. With an M-bcr-3' probe, we cloned and characterized a 3' junction fragment. Field inversion gel electrophoresis and chromosome in situ hybridization studies using a probe isolated from genomic DNA 5' of the junction showed that 3' M-BCR was joined to a region of chromosome 9q34 rich in repetitive sequences and lying some distance 3' of ABL. The chromosome 9 insert was at least 329 kilobases long and included 3' ABL and a larger portion of chromosome 9q34. Our results allowed us to exclude transposon- or retroviral-mediated insertion of ABL into chromosome 22. Instead, we favored a two-translocation model in which a second translocation reconstituted a standard t(9;22)(q34;q11) but left the chromosome 9 insert, including 3' ABL, in chromosome 22.
authors.affiliation: Department of Pathology, Children's Hospital of Los Angeles, CA.
authors.forename: C M
authors.initials: CM
authors.lastname: Morris
authors.forename: N
authors.initials: N
authors.lastname: Heisterkamp
authors.forename: M A
authors.initials: MA
authors.lastname: Kennedy
authors.forename: P H
authors.initials: PH
authors.lastname: Fitzgerald
authors.forename: J
authors.initials: J
authors.lastname: Groffen
mesh_terms: D002678:Chimera / Q000235:genetics; D002874:Chromosome Mapping; D002892:Chromosomes, Human, Pair 22; D002899:Chromosomes, Human, Pair 9; D004247:DNA / Q000235:genetics; D004251:DNA Transposable Elements; D004591:Electrophoresis, Polyacrylamide Gel; D016044:Fusion Proteins, bcr-abl / Q000235:genetics; D016313:Genes, abl / Q000235:genetics; D006801:Humans; D054438:Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D011505:Protein-Tyrosine Kinases; D011518:Proto-Oncogene Proteins / Q000235:genetics; D051562:Proto-Oncogene Proteins c-bcr; D014178:Translocation, Genetic
chemical_list: D004251:DNA Transposable Elements; D011518:Proto-Oncogene Proteins; D004247:DNA; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl; C496613:BCR protein, human; D051562:Proto-Oncogene Proteins c-bcr