Novel bcl-2 breakpoints in patients with follicular lymphoma.
Using genomic DNA from patients with follicular lymphoma, we performed polymerase chain reaction (PCR) amplifications to detect t(14;18) translocations. Unexpectedly large products of approximately 1 kilobase (kb) were detected by gel electrophoresis in 2 of 50 positive cases. In these 2 cases, sequence analyses showed novel breakpoints in the 3' untranslated region of bcl-2, approximately 800 bp downstream of the major breakpoint region (mbr). The breakpoints in IgH occurred in JH4 in one patient and JH5 in the other. Sequences just upstream of the new bcl-2 breakpoints suggest a mechanism of translocation that may include minisatellite core-mediated recombination. In one of our two patients with novel bcl-2 breakpoints, the approximately 1 kb product obtained using conventional mbr primers was detectable only when a nested PCR was performed. These findings have important implications for diagnosis and minimal residual disease detection in t(14;18)-positive lymphomas.
Department of Pathology and Laboratory Medicine, University of Pennsylvania Medical Center, Philadelphia 19104, USA.
Y L
YL
Wang
K
K
Addya
R H
RH
Edwards
H
H
Rennert
L
L
Dodson
D G
DG
Leonard
R B
RB
Wilson
D000328:Adult; D001483:Base Sequence; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics / Q000648:ultrastructure; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics* / Q000648:ultrastructure; D004273:DNA, Neoplasm / Q000235:genetics*; D005260:Female; D005803:Genes, Immunoglobulin / Q000235:genetics; D019254:Genes, bcl-2; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D008224:Lymphoma, Follicular / Q000235:genetics* / Q000473:pathology; D008969:Molecular Sequence Data; D018365:Neoplasm, Residual; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014178:Translocation, Genetic
D004273:DNA, Neoplasm; D007143:Immunoglobulin Heavy Chains