Low incidence of TEL/AML1 fusion and TEL deletion in Korean childhood acute leukemia by extra-signal fluorescence in situ hybridization.
TEL/AML1 fusion in acute leukemia results from cryptic translocation of chromosome 12 and 21, the presence of which suggests a favorable prognosis. The incidence of TEL/AML1 fusion in B-lineage ALL is approximately 25%, but the incidence in Korea has not yet been reported. To investigate the incidence of TEL/AML1 fusion and TEL deletion, bone marrow specimens from 77 Korean children with newly diagnosed acute leukemia were analyzed by FISH. We applied extra-signal FISH to discriminate a true TEL/AML1 fusion from a false-positive fusion signal. To determine the cut-off value of the TEL/AML1 fusion signal, 20 normal bone marrow specimens and 28 normal peripheral blood specimens were also analyzed. The frequency of patients with TEL/AML1 fusion was 13.3% (4 cases) among 30 B-lineage ALL and 9.5% among 42 ALL. One TEL/AML1 fusion-positive patient was also found among 4 acute biphenotypic leukemias. TEL/AML1 fusion was not found in any samples from patients with T-lineage ALL or AML. The incidence of TEL deletion was 6.7% (2 cases) among 30 B-lineage ALL and 4.8% among 42 ALL. The incidences of TEL/AML1 fusion and TEL deletion in Korean children with acute leukemia appear to be lower than those in other countries, suggesting a racial difference.
Park
K U
KU
The Department of Clinical Pathology, Seoul National University College of Medicine, 28 Yungon-dong, Chongno-gu, 110-744, Seoul, South Korea.
She
C J
CJ
Shin
H Y
HY
Ahn
H S
HS
Kim
C J
CJ
Cho
B K
BK
Cho
H I
HI
Lee
D S
DS
D050676:Core Binding Factor Alpha 2 Subunit; D015342:DNA Probes; D004268:DNA-Binding Proteins / Q000235:genetics*; D017353:Gene Deletion; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D007723:Korea; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000208:ethnology / Q000235:genetics* / Q000276:immunology; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins; D014157:Transcription Factors / Q000235:genetics*; D000097764:ETS Translocation Variant 6 Protein
D050676:Core Binding Factor Alpha 2 Subunit; D015342:DNA Probes; D004268:DNA-Binding Proteins; D015514:Oncogene Proteins, Fusion; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins; D014157:Transcription Factors; D000097764:ETS Translocation Variant 6 Protein; C102421:TEL-AML1 fusion protein