Detection of a novel CBFB/MYH11 variant fusion transcript (K-type) showing partial insertion of exon 6 of CBFB gene using two commercially available multiplex RT-PCR kits.
We report on a 20-year-old man with acute myeloid leukemia (AML) showing a distinct novel CBFB/MYH11 variant fusion transcript. Initial results of bone marrow, chromosome, and flow cytometric analyses were not in accordance with the diagnosis of acute myelomonocytic leukemia with eosinophilia (AML-M4Eo) or AML with a CBFB/MYH11 rearrangement. However, results from 2 commercially available multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) tests repeatedly showed an unusual PCR product from his bone marrow specimen. Not only does this case show a partial insertion of exon 6 of the CBFB (ENSG00000067955) gene, but it also involves novel breakpoints within both exon 6 of the CBFB gene and exon 28 (previously exon 7) of the MYH11 (ENSG00000133392) gene, which is regarded as a previously non-reported, new type (K-type) of CBFB/MYH11 fusion transcript. In addition, our study result was in agreement with the recent report of Schnittger et al. that rare fusion transcripts of CBFB/MYH11 are correlated with an atypical cytomorphology and other aberrant characteristics. Therefore, multiplex RT-PCR and sequence analysis of these atypical products should be performed to diagnose atypical AML with CBFB/MYH11 rearrangement, to predict prognosis of these patients as well as to elucidate the molecular mechanism.
Park
Tae Sung
TS
Department of Laboratory Medicine, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752, Korea.
Lee
Seung Tae
ST
Song
Jaewoo
J
Lee
Kyung-A
KA
Lee
Jong-Han
JH
Kim
Juwon
J
Lee
Hyeon-Ji
HJ
Han
Jeong-Hyun
JH
Kim
Jong-Kee
JK
Cho
Sung Ran
SR
Choi
Jong Rak
JR
D001483:Base Sequence; D050658:Core Binding Factor beta Subunit / Q000235:genetics*; D020732:Cytogenetic Analysis; D004252:DNA Mutational Analysis / Q000295:instrumentation / Q000379:methods; D005091:Exons; D052138:Genes, Neoplasm; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D018995:Myosin Heavy Chains / Q000235:genetics*; D011933:Reagent Kits, Diagnostic; D011993:Recombinant Fusion Proteins / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D055815:Young Adult
C493692:CBFB protein, human; D050658:Core Binding Factor beta Subunit; C509903:MYH11 protein, human; D011933:Reagent Kits, Diagnostic; D011993:Recombinant Fusion Proteins; D018995:Myosin Heavy Chains