Genetics analysis of two childhood acute myeloid leukemia patients with variant t(8;21) / 白血病·淋巴瘤

ABSTRACT

Objective To report two childhood acute myeloid leukemia (AML) patients with t(8;20)(q22;q13) and t(1;8;21)(q32;q22;q22) respectively,as variant t(8；21).Methods Chromosome preparation of bone marrow cells were made using short-term culture and karyotypic analysis was carried out using R and G-banding techniques.Interphase-fluorescence in situ hybridization (I-FISH) and metaphase-FISH (M-FISH) were performed using dual color,dual fusion AML1-ETO probe to detect the AML1-ETO fusion gene.Multiplex RT-PCR was used to demonstrate the expression of AML1-ETO fusion transcript.Results The karyotype of bone marrow cells for these two childhood AML patients were 45,X,-Y,t(8;20)(q22;q13)[12]/46,XY[3](case 1) and 46,XX,t(1;8;21)(q32；q22;q22)[18]/46,XX[2](case 2),respectively.I-FISH and M-FISH confirmed that they all had the AML1-ETO fusion gene and variant t(8;21).The AML1-ETO fusion transcript in both patients was detected by RT-PCR.Conclusion t (8;20)(q22;q13) and t (1;8;21)(q32;q22;q22) are variant t (8;21) in nature.It is important to combine the conventional karyotypic analysis with D-FISH and multiplex RT-PCR to determine the nature and prognosis of AML patients with variant t(8;21).