PMID- 10629589
OWN - NLM
STAT- MEDLINE
DCOM- 20000414
LR  - 20131121
IS  - 0390-6078 (Print)
IS  - 0390-6078 (Linking)
VI  - 85
IP  - 1
DP  - 2000 Jan
TI  - Complex chromosome rearrangements may locate the bcr/abl fusion gene sites other 
      than 22q11.
PG  - 35-9
AB  - BACKGROUND AND OBJECTIVE: From 5-8% of Philadelphia (Ph) positive patients with 
      chronic myeloid leukemia (CML) show variant translocations in which at least a 
      third chromosome in addition to 9q34 and 22q11 is involved. The formation 
      mechanisms and clinical significance of variant Ph translocations are still 
      unclear. The BCR/ABL chimeric gene encoding for chimeric proteins is always 
      present and maps on the 22q- regardless of the type of translocation. We studied 
      two apparently Ph negative CML patients with unusual karyotypes both showing a 
      typical b3a2 rearrangement. DESIGN AND METHODS: Dual-color fluorescence in situ 
      hybridization (FISH) can visualize BCR and ABL genes and localize the BCR/ABL 
      fusion gene. We used FISH to study the formation mechanisms of variant Ph 
      translocations in two patients. RESULTS: The chimeric BCR/ABL gene was located on 
      a locus other than the expected 22q11 in both patients. In the first case the 
      fusion signal was present on the 9q34 band whereas in the second patient it was 
      detected on chromosome 8, involved in masked Ph formation. INTERPRETATION AND 
      CONCLUSIONS: The location of the hybrid BCR/ABL gene on chromosomes other than 
      22q- is a rare event which can only be observed using the FISH technique. When 
      these unusual translocations occur the hypothesis most often put forward is that 
      several consecutive cytogenetic events have taken place. The factors which 
      regulate the formation of these breakpoints have yet to be clarified. The FISH 
      technique allows the identification of chromosome rearrangements that could not 
      otherwise be detected by conventional banding procedures. The location of the 
      hybrid BCR/ABL gene on sites other than 22q11 represents a rare type of variant 
      Ph translocation. The real frequency and clinical significance of such 
      rearrangements need to be investigated.
FAU - Sessarego, M
AU  - Sessarego M
AD  - Department of Internal Medicine, University of Genoa, viale Benedetto XV 6, 16132 
      Genoa, Italy. masessar@unige.it.
FAU - Fugazza, G
AU  - Fugazza G
FAU - Bruzzone, R
AU  - Bruzzone R
FAU - Ballestrero, A
AU  - Ballestrero A
FAU - Miglino, M
AU  - Miglino M
FAU - Bacigalupo, A
AU  - Bacigalupo A
LA  - eng
PT  - Case Reports
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Italy
TA  - Haematologica
JT  - Haematologica
JID - 0417435
RN  - 0 (Neoplasm Proteins)
RN  - EC 2.7.10.2 (Fusion Proteins, bcr-abl)
SB  - IM
MH  - Aged
MH  - Chromosomes, Human, Pair 10/genetics
MH  - Chromosomes, Human, Pair 22/genetics
MH  - Chromosomes, Human, Pair 9/genetics
MH  - Female
MH  - Fusion Proteins, bcr-abl/*genetics
MH  - Humans
MH  - In Situ Hybridization, Fluorescence
MH  - Karyotyping
MH  - Leukemia, Myelogenous, Chronic, BCR-ABL Positive/*genetics
MH  - Middle Aged
MH  - Neoplasm Proteins/genetics
MH  - *Philadelphia Chromosome
MH  - Translocation, Genetic/*genetics
EDAT- 2000/01/12 09:00
MHDA- 2000/04/25 09:00
CRDT- 2000/01/12 09:00
PHST- 2000/01/12 09:00 [pubmed]
PHST- 2000/04/25 09:00 [medline]
PHST- 2000/01/12 09:00 [entrez]
PST - ppublish
SO  - Haematologica. 2000 Jan;85(1):35-9.