中国图书资料分类法分类号R733.72
Application of fluorescence in situ hybridization in detecting the formation of variant Philadelphia translocation in chronic myeloid leukemia
HONG Bo, QIU Jing-Ying, DANG Hui, SHI Yan, HE Qi, LU Dao-Pei
(Institute of Hematology, People's Hospital, Beijing Medical University, Beijing100034)
MeSHLeukemia, myelomonocytic, chronic/genetIn situ hybridization, fluorescenceChromosome aberrationsVariation(Genetics)Philadelphia chromosome
ABSTRACTObjective: To detect the formation of variant Philadelphia translocation in chronic myeloid leukemia (CML).Methods: Whole chromosome specific DNA probe for chromosome 9,15,22 and M-bcr/abl translocation probe were used to detect variant Ph chromosome in metaphase and interphase nuclei of 7 CML patients by FISH.Results: All variant Ph translocation involved at least three chromosomes and derived from a standard Ph translocation t ( 9 ; 22 )(q34 ; q11).Conclusion: FISH is more sensitive than the conventional cytogenetic method and can be applied to the accurate analysis of variant Ph translocation and the process of its formation.
(J Beijing Med Univ, 1999,31:400-403)
Ph染色体是慢性粒细胞性白血病(chronic myeloid leukemia, CML)特有的染色体异常,是9号与22号染色体易位所致,5%~10%Ph染色体阳性CML患者具有与 标准易位t ( 9 ; 22 ) ( q34; q11) 不同的变异易位[1]。由于变异Ph染色体易位的多样性,用传统细胞遗传学带型分析的方法进行准确检测存在一定困难,荧光原位杂交技术的开展,提高了对染色体畸变检出的敏感性,对变异易位的划分及形成过程能够更准确地认识,有利于进一步了解变异 Ph 染色体的性质及在CML病程中的作用, 为此本研究采用中期分裂相和间期细胞荧光原位杂交( fluorescence in situ hybridization,FISH ),并结合带型分析对7例CML病人的变异Ph染色体进行了分析。
1材料与方法
病例选择及染色体标本制备、带型分析: 7例患者形态学按FAB标准诊为CML,患者均处于慢性期,患者骨髓血经24 h短期培养,培养终止前2 h加入秋水仙素,常规收获、固定后进行G显带分析[2],剩余标本滴片后置-20℃保存,待原位杂交用。
荧光原位杂交:所用探针为地高辛(Digoxigenin)标记的9号与22号染色体全长探针(Oncor公司),生物素( Biotin)标记的15号染色体全长探针(质粒DNA为Dr. Speicher赠送,探针纯化、标记见文献[3]),以及双色(橙色与绿色)荧光素直接标记的M-bcr/abl DNA探针(美国陈忠博士赠送)。原位杂交方法参照Pinkel等方法加以改进。
9号与22号染色体全长探针杂交的标本以FITC偶联的抗地高辛抗体检测,15号染色体全长探针杂交的标本以FITC偶联的抗生物素抗体检测,最后加入含PI和DAPI的抗淬灭剂及盖玻片于荧光显微镜下观察,用470~500nm蓝光激发,染色体、间期细胞呈红色,杂交信号为黄色;用330~370nm紫外光激发时,染色体及细胞呈蓝白色,形态清晰。双色荧光素(橙色与绿色)直接标记的M-bcr/abl 探针杂交的标本,经杂交后洗片,并加入含DAPI Ⅱ的抗淬灭剂和盖玻片后,用可激发DAPI/TRITC/FITC的三色滤光块观测,细胞及染色体呈灰蓝色,9号染色体q34处可见绿色点状杂交信号,22号染色体q11处可见红色杂交信号,间期细胞中亦可见相应的杂交信号。若9号与22号染色体正常,则可见彼此分离的2个红色点状杂交信号及2个绿色点状信号。在具有t(9;22)易位的间期细胞中,可见1个红色点状信号、1个绿色点状信号和1个红绿点紧靠在一起或相互叠加产生的黄色点状信号,用ASA1600 Kodak彩色胶卷拍照记录。
2结果
7例患者G显带分析、FISH结果以及应用的探针见表1及图1~9。
表17例CML患者G显带和荧光原位杂交结果
Table 1G-banding and FISH results of 7 patients with CML
Case G-banding FISH Results No. ofmetaphase
analyzed Results No. of
metaphase
analyzed Probes used 1 46,XY,t(9;9;22) 23 46,XY,t(9;9;22) 65 WCP for chromosome 9,22 2 46,XX,t(5;9;15;22) 25 46,XX,t(5;9;15;22) 56 WCP for chromosome9,22,15 3 46,XY,t(10;12;22) 31 46,XY,t(9;12;22) 37 WCP for chromosome9,22 4 46,XY,t(11;22) 20 46,XY,t(9;11;22) 38 WCP for chromosome9,22; 30 M-bcr/abl DNA probe 500(I)* 5 46,XX,t(5;9;22) 30 46,XX,t(5;9;22) 100 WCP for chromosome9 6 45,X,-Y,t(14;22) 20 45,X,-Y,t(9;14;22) 67 WCP for chromosome9,22; 30 M-bcr/abl DNA probe 500(I)* 7 46,XY,t(19;21;22) 28 46,XY,t(9;19;21;22) 124 WCP for chromosome9,22; 30 M-bcr/abl DNA probe 500(I)*
WCP: whole chromosome probe; (I)*interphase nuclei.
图1例3用9号染色体全长探针杂交。a,b: 9号染色体;c: Ph染色体;e: 参与易位的12号染色体。
Figure 1Painting probe for chromosome 9 displays the presence of signals on two chromosome 9(a,b); Ph chromosome(c); one der(12)(e).
图2,3例4分别用9号(图2)、22号(图3)染色体全长探针杂交。a,b: 9号染色体; c: Ph染色体; d: 正常22号染色体;e: 参与易位的11号染色体短臂。
Figure 2,3Painting probes for chromosome 9(Fig.2) and chromosome 22(Fig.3) display the presence of signals on two chromosome 9(a,b);Ph chromosome(c);one normal chromosome 22(d) and p arm of der(11) (e).
图4,5例6分别用9号(图4)、22(图5)号染色体全长探针杂交。a,b: 9号染色体;c: Ph染色体;d: 正常22号染色体;e: 参与易位的14号染色体。
Figure 4,5Painting probes for chromosome 9(Fig.4) and chromosome 22(Fig.5)display the presence of signals on two chromosome 9(a,b);Ph chromosome(c);one normal chromosome22(d);one der(14) (e).
