Sharma P, Watson N, Robson L, Gallo J, Smith A
Department of Cytogenetics, New Children's Hospital, Westmead, NSW, Australia.
Cancer Genet Cytogenet. 1999 Aug;113(1):25-8. doi: 10.1016/s0165-4608(99)00008-4.
Inversion of chromosome 16 is a common feature of acute myeloid leukemia (AML) M4, while t(16;21), although also associated with AML, appears to be a separate entity. We present a patient with myelodysplastic syndrome (MDS) who transformed to AML-M1. The karyotype was normal at diagnosis; at 15 months, hematological evidence of transformation was present, and repeat cytogenetics showed a novel rearrangement of one chromosome 16. Two breaks had occurred; one in the short arm at 16p11, with translocation of the segment distal to this onto chromosome 21q, and the other in the long arm at 16q22 with subsequent deletion of the segment from 16q22-->qter. Fluorescence in situ hybridization (FISH) confirmed the abnormalities detected by cytogenetics and excluded involvement of the AML1 gene on 21q22. While the 16q22 breakpoint was at the usual site for the inv(16), the 16p11 was not. The patient is more characteristic of t(16;21) than inv(16), and adds to the spectrum of chromosome 16 abnormalities in AML.
16号染色体倒位是急性髓系白血病（AML）M4的常见特征，而t(16;21)虽然也与AML相关，但似乎是一个独立的实体。我们报告了一名骨髓增生异常综合征（MDS）患者，该患者转化为AML-M1。诊断时核型正常；15个月时，出现了转化的血液学证据，重复细胞遗传学检查显示一条16号染色体发生了新的重排。发生了两处断裂；一处在短臂16p11处，该段远端片段易位至21号染色体q臂，另一处在长臂16q22处，随后16q22至qter片段缺失。荧光原位杂交（FISH）证实了细胞遗传学检测到的异常，并排除了21q22上AML1基因的受累情况。虽然16q22断点位于inv(16)的常见位点，但16p11不是。该患者更符合t(16;21)而非inv(16)的特征，并增加了AML中16号染色体异常的范围。
