PMC8555453_01
Representative karyotype showing 46,XY,inv(16)(p13.1q22)[10].
1414-431X-bjmbr-54-12-e11605-gf001.jpg
PMC8555453_01_1414-431X-bjmbr-54-12-e11605-gf001.jpg
f01
Immunophenotyping of bone marrow cells showed 5.65% blasts, expressing CD34, CD117, CD13, HLA-DR, lack of CD7, CD10, CD38, CD33, CD11C, CD11b, CD64, CD15, CD19, CD123, CD56, CD36, CDCR4, CD14, CD300e, CD4, and CD2 (Supplementary Figure S1). Karyotype analysis demonstrated 46,XY,inv(16)(p13.1q22)[10] (Figure 1).
FISH result using the double color separation CBFbeta probe (VYSIS), green fluorescent-labeled 3'CBFbeta (16q22) probe, and red fluorescent-labeled 5'CBFbeta probe. Split CBFbeta abnormal signals on chromosome 16 (2R and 2G) are observed in interphase tetraploid cell nuclei.
1414-431X-bjmbr-54-12-e11605-gf002.jpg
PMC8555453_01_1414-431X-bjmbr-54-12-e11605-gf002.jpg
f02
The rearrangement of the CBFbeta gene fusion was detected on chr16 (Figure 2).
Gel electrophoresis and sequence analysis of the CBFbeta/MYH11 transcript. A, Gel electrophoresis 111/121 and 112/122 primer pairs used for amplification of the CBFbeta/MYH11 transcript. E2A is the internal reference primer. M1 is the DNA molecular weight marker 1 (100-600 bp, Tiangen, China). 111/121 amplified product showed a specific band between 200-300bp. B, Sequence analysis of the CBFbeta/MYH11 transcript showed a breakpoint between exon 4 of the CBFbeta gene and exon 34 of the MYH11 gene.
1414-431X-bjmbr-54-12-e11605-gf003.jpg
PMC8555453_01_1414-431X-bjmbr-54-12-e11605-gf003.jpg
f03
A rare fusion transcript of CBFbeta/MYH11 was detected, and electrophoresis of the PCR amplified product showed a positive band between 200-300bp (Figure 3A). CBFbeta exon4 and MYH11 exon34 were fused to form the fusion transcript. Comparing the CCDS sequence of the NCBI database, the CBFbeta/MYH11 fusion transcript belonged to a rare type I fusion transcript (Figure 3B).