【摘要】 目的　分析染色体 - 7/ 7q-在骨髓增生异常综合征 (myelodysplastic syndrome,MDS)和急性髓细胞白血病 (acute myeloblastic leukemia,AML )中的发生频率 ;探讨荧光原位杂交技术 (fluorescencein situ hybridization,FISH)在检测和鉴定 - 7/ 7q-异常中的价值。　方法　回顾性分析所有接受细胞遗传学分析 (conventional cytogenetic analysis,CCA)的 MDS/ AML患者的核型特征 ,其中 70份进行 FISH分析。应用双色荧光直接标记的 7号着丝粒探针 (CEP7,光谱绿 )和 7q31基因序列探针 (D7S4 86 ,光谱桔红 ) ,15份正常样本作为对照。　结果　 - 7/ 7q-在 AML 和 MDS中出现频率分别为 4 .5 1% (31/ 6 87例 )和 5 .71% (2 8/ 4 90例 ) ,分别占异常核型病例的 5 .6 8%和 10 .2 9%。 7q-常见的缺失区域为 7q2 1- 2 2 (10例 )和 7q31- 35 (10例 )。FISH证实伴有克隆性 - 7/ 7q-异常 ,但在随机性 - 7/ 7q-异常或正常核型中未检出 - 7/ 7q-异常。在核型分析出现 7q-异常的病例中 ,FISH检出 7/ 11例可同时伴有 - 7克隆的出现 ,而且 7q-异常的细胞数显著高于 - 7异常细胞数 (4 2 .5 % vs 8.4 % ,P=0 .0 2 5 )。 1例核型为 del(7) (q2 2 )患者 FISH证实为染色体易位 ;1例 7q+患者 FISH显示 dup(7q) ;1例复杂异常核型 ,FISH更多还原

【Abstract】 Objective To accurately evaluate the incidence of -7/7q- abnormality in acute myeloblastic leukemia (AML) and myelodysplastic syndrome (MDS) patients and investigate the value of fluorescence in situ hybridization (FISH) technique in the detection and identification of -7 and 7q abnormality. Methods A FISH assay was performed to analyze 70 AML/MDS patients who had received conventional cytogenetic analysis (CCA). The dual color probes CEP 7 labeled by SpectrumGreen and D7S486 (locus at 7q31) labeled by SpectrumOrange were used. Results The incidence of -7/7q- in AML and MDS patients was 4.51% (31 out of 687 cases) and 5.71%(28 out of 490 cases), respectively, and was 5.68% and 10.29% in these patients with abnormal karyotype, respectively. The common deletion region of 7q- was 7q21-22 (ten cases) and 7q31-35(ten cases). FISH assay confirmed the -7/7q- aberration in those with clonal -7/7q- abnormalities, but failed in those with random -7/7q- and normal karyotype. In 7q- group, FISH revealed seven of eleven cases with monosomy 7 clone detected in the same specimen, but the numbers of 7q- interphases cells were much greater than those of monosomy 7 cells (average 42.5% vs 8.4%, P=0.025). FISH also provided precise refinement for three chromosomal structural abnormalities associated with 7q seen in CAA, one case with del(7)(q22) being refined as chromosomal translocation, one case with 7q+ being confirmed as dup(7q), and one case with complex translocation involving 7q being also proved to be true. Conclusion FISH is a powerful tool to identify or refine chromosomal structural aberrations involving 7q, and it provides accurate evaluation of -7/7q- in all the patients. -7 and 7q- clone frequently coexist in the same specimen, and the significantly increasing percentage of 7q- cells implies that -7 clone secondary to 7q- clone is a result from loss of 7q-.更多还原