Jumping translocation of 17q11 approximately qter and 3q25 approximately q28 duplication in a variant Philadelphia t(9;14;22)(q34;q32;q11) in a childhood chronic myelogenous leukemia.
The virtually obligatory presence of the Philadelphia chromosome may suggest a causal homogeneity, but chronic myelogenous leukemia (CML) is a clinically heterogeneous disease. This may be a consequence of the variable BCR breakpoints on chromosome 22 and of nonrandom secondary chromosomal abnormalities. We present the case of a boy, age 12, investigated in blastic phase of CML. Karyotyping with conventional and multiplex fluorescence in situ hybridization (FISH and M-FISH) karyotyping, complemented with reverse transcriptase-polymerase chain reaction, identified a variant Philadelphia translocation t(9;14;22)(q34;q32;q11) involving a cryptic BCR/ABL fusion with formation of the p190(Bcr-Abl) oncoprotein. M-FISH revealed also an unbalanced jumping translocation of 17q11 approximately qter alternatively present on chromosomes 14 or 20, apparently hithertofore unreported in hematological malignancies. Another secondary aberration, dup(3)(q25q28), was revealed by multipoint interphase FISH (mpI-FISH). Gain of this region is known in adult hematological malignancies and solid tumors, suggesting its general involvement in tumor initiation or progression (or both), regardless of tissue origin.
Haltrich
Irén
I
Semmelweis University, Faculty of Medicine, II. Department of Pediatrics, Budapest, Hungary.
Kost-Alimova
Maria
M
Kovács
Gábor
G
Kriván
Gergely
G
Tamáska
Júlia
J
Klein
George
G
Fekete
György
G
Imreh
Stefan
S
D002648:Child; D002869:Chromosome Aberrations; D002886:Chromosomes, Human, Pair 17; D002893:Chromosomes, Human, Pair 3; D016044:Fusion Proteins, bcr-abl / Q000235:genetics; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics*; D008297:Male; D010677:Philadelphia Chromosome; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014178:Translocation, Genetic
D016044:Fusion Proteins, bcr-abl