Jang Ja-Hyun, Yoo Eun-Hyung, Kim Hee-Jin, Kim Dong-Hwan, Jung Chul-Won, Kim Sun-Hee
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Ann Clin Lab Sci. 2010 Winter;40(1):80-4.
A 57-yr-old woman was diagnosed with acute myeloid leukemia (AML) with maturation, based on morphological and cytochemical/immunophenotypic findings on bone marrow studies. Conventional cytogenetic analysis using bone marrow cells revealed terminal deletion of the short arm of an X chromosome as 46,X,del(X)(p21)[8]/46,XX[12]. On the other hand, fluorescence in situ hybridization (FISH) for the RUNX1/RUNX1T1 (formerly AML1/ETO) rearrangement revealed 86% interphase nuclei with one fusion signal, which was found to be on the long arm of chromosome 8 on metaphase FISH, indicating the RUNX1/RUNX1T1 rearrangement by cryptic insertion of the RUNX1 gene. Molecular genetic study by reverse transcriptase polymerase chain reaction (RT-PCR) confirmed the presence of the chimeric transcript. The final karyotype was 46,X,del(X)(p21).ish ins(8;21)(q22;q22q22)(RUNX1T1+,RUNX1+;RU NX1+,RUNX1T1-)[8]/46,XX[12]. In addition to the cryptic RUNX1/RUNX1T1 rearrangement, this is the first report of partial deletion of an X chromosome as an additional cytogenetic aberration in AML with RUNX1/RUNX1T1.
一名57岁女性，根据骨髓检查的形态学和细胞化学/免疫表型结果，被诊断为急性髓系白血病伴成熟。使用骨髓细胞进行的传统细胞遗传学分析显示，一条X染色体短臂末端缺失，核型为46,X,del(X)(p21)[8]/46,XX[12]。另一方面，针对RUNX1/RUNX1T1（以前称为AML1/ETO）重排的荧光原位杂交（FISH）显示，86%的间期核有一个融合信号，在中期FISH中发现该信号位于8号染色体长臂上，表明RUNX1基因通过隐匿性插入导致RUNX1/RUNX1T1重排。通过逆转录聚合酶链反应（RT-PCR）进行的分子遗传学研究证实了嵌合转录本的存在。最终核型为46,X,del(X)(p21).ish ins(8;21)(q22;q22q22)(RUNX1T1+,RUNX1+;RUNX1+,RUNX1T1-)[8]/46,XX[12]。除了隐匿性RUNX1/RUNX1T1重排外，这是首次报道在伴有RUNX1/RUNX1T1的急性髓系白血病中，X染色体部分缺失作为一种额外的细胞遗传学异常。
