Rieder H, Schnittger S, Bodenstein H, Schwonzen M, Wörmann B, Berkovic D, Ludwig W D, Hoelzer D, Fonatsch C
Institut für Humangenetik, Medizinische Universität, Lübeck, Federal Republic of Germany.
Genes Chromosomes Cancer. 1995 May;13(1):54-61. doi: 10.1002/gcc.2870130109.
Loss of chromosome 20 and rearrangement of the short arm of chromosome 9 were identified by banding analysis of three adult patients with acute lymphoblastic leukemia (ALL). The G-banding pattern suggested an identical deletion of 9p, but, also, an unbalanced translocation with chromosome 20 was taken into consideration. Dual-color chromosome painting with probes for chromosomes 9 and 20 revealed the presence of material from chromosome 20 at the short arm of the abnormal chromosome 9 in all three cases. Centromeric alpha-satellite DNA of both chromosome 9 and chromosome 20 was demonstrated by fluorescence in situ hybridization and indicated the presence of a dicentric chromosome. The hybridization of a YAC clone of the short arm of chromosome 20 proved that the dicentric chromosome contained the short arm of chromosome 20, which had been suspected from the G-banding pattern. Thus, the rearrangement was interpreted as dic(9;20)(p11;q11.?1). Because this was the sole chromosome abnormality in two patients, dic(9;20) may be a primary chromosome aberration in ALL. In one case, a 9q+ chromosome derived from a Philadelphia (Ph) translocation was involved in the formation of the dicentric chromosome. Immunophenotyping revealed CD10+ B-cell precursor ALL in all three cases. Whereas the two patients in whom dic(9;20) was the sole cytogenetically detectable change are in continuous complete remission for 10 and 45 months, respectively, the Ph+ patient relapsed with leukemia and died 8 months after diagnosis.
通过对三名成年急性淋巴细胞白血病（ALL）患者进行显带分析，发现了20号染色体缺失以及9号染色体短臂重排。G显带模式提示9p存在相同的缺失，但同时也考虑到与20号染色体的不平衡易位。用9号和20号染色体探针进行双色染色体描绘显示，在所有三例中，异常9号染色体短臂上均存在来自20号染色体的物质。荧光原位杂交显示了9号和20号染色体的着丝粒α卫星DNA，表明存在双着丝粒染色体。20号染色体短臂的YAC克隆杂交证明，双着丝粒染色体包含20号染色体短臂，这从G显带模式中就已怀疑。因此，这种重排被解释为dic(9;20)(p11;q11.?1)。由于这是两名患者唯一的染色体异常，dic(9;20)可能是ALL中的原发性染色体畸变。在一例中，源自费城（Ph）易位的9q+染色体参与了双着丝粒染色体的形成。免疫表型分析显示，所有三例均为CD10+ B细胞前体ALL。dic(9;20)是唯一可通过细胞遗传学检测到的变化的两名患者，分别持续完全缓解了10个月和45个月，而Ph+患者白血病复发，诊断后8个月死亡。
