Distribution of breakpoint within the breakpoint cluster region (bcr) in chronic myelogenous leukemia with a complex Philadelphia chromosome translocation.
We analyzed, by Southern blot hybridization, the site of breakpoint within the breakpoint cluster region (bcr) in six patients with a complex Philadelphia chromosome (Ph) translocation and in 23 unselected patients with a standard Ph. The breakpoint was found within the 5.8 kb bcr in all 29 patients. When the bcr was subdivided into four parts, fragments I-IV, based on the restriction enzyme sites, among the six patients with a complex Ph, two had a breakpoint at fragment I, three at fragment II, and one at fragment III. This distribution of breakpoints in patients with a complex Ph did not differ significantly from that in patients with a standard Ph. A deletion of an allele within the bcr was found in three patients (50%) with a complex Ph and in three (13%) with a standard Ph. The internal bcr deletion may be more common in patients with a complex Ph.
Nishigaki
H
H
Third Department of Internal Medicine, Kyoto Prefectural University of Medicine, Japan.
Inazawa
J
J
Misawa
S
S
Nishida
K
K
Okuda
T
T
Horiike
S
S
Tsuda
S
S
Taniwaki
M
M
Abe
T
T
D000483:Alleles; D002872:Chromosome Deletion; D002908:Chronic Disease; D015321:Gene Rearrangement; D006801:Humans; D007621:Karyotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics*; D010677:Philadelphia Chromosome; D014178:Translocation, Genetic