七例产前诊断的标记染色体及复杂染色体畸变的光谱核型分析

目的 探讨光谱核型分析( spectral karyotyping,SKY)结合荧光原位杂交(fluorescence in situ hybridization,FISH)及传统核型分析技术在产前诊断标记染色体及复杂染色体畸变中的应用.方法 对产前诊断中常规G显带分析发现的5例标记染色体以及2例复杂染色体畸变的胎儿样本进行SKY分析,必要时应用FISH技术进一步鉴定或采用C显带、N显带技术进行辅助诊断,并分析胎儿产前超声检查、生后随访或病理解剖结果.结果 5例标记染色体的病例中2例为大的标记染色体,3例为中等大小标记染色体;1例胎儿为父源性遗传,4例为新发突变.用SKY分析发现2例为非近端着丝粒来源(分别为4号、9号染色体),2例为近端着丝粒来源(分别来自22号、21号染色体),1例为X染色体来源.3例经FISH检查证实了SKY分析结果.5例标记染色体的胎儿4例终止妊娠,1例父源性遗传者足月分娩,生后随访1年未见异常.2例产前诊断为复杂染色体畸变的胎儿,其中1例经常规G显带分析为不明来源的衍生染色体,SKY诊断为8号染色体自身部分重复;另1例经SKY诊断为2号与6号染色体易位的胎儿足月分娩,随访6个月时有生长发育迟缓.结论 应用SKY结合FISH及传统的核型分析可对产前诊断中难以确定来源的标记染色体及复杂染色体畸变作出诊断,结合超声波检查结果,可更好地为临床咨询提供指导.     

光谱核型分析联合微阵列比较基因组杂交诊断15号环状染色体综合征

目的 探讨联合应用光谱核型分析技术(spectral karyotyping,SKY)和微阵列比较基因组杂交技术(microarray-based comparative genomic hybridization,array-CGH)在诊断复杂疑难的环状染色体畸变中的价值.方法 对1例常规G显带染色体核型分析疑诊为46,XY,r(15)?的8岁男性生长发育迟缓患儿依次应用SKY及array-CGH技术常规进行制片杂交,并通过相应的显微摄像系统和计算机软件分析结果.结果 SKY技术明确了该患儿环状染色体来源于15号染色体,array-CGH技术明确患儿15q26.3末端存在约594 kb的缺失,染色体基因位点编码范围为99689349-100282878.结论 联合应用现代分子细胞遗传学技术可以从细胞到分子水平精确诊断复杂疑难的环状染色体病例,是常规染色体核型分析的有益补充,也有利于细胞遗传学向分子水平深入.     

综合应用分子细胞遗传学技术检测一例染色体微小易位

目的 综合应用分子细胞遗传学技术对1例染色体微小易位的病例进行检测.方法 按常规制备染色体,G显带进行核型分析,并先后进行光谱核型分析(spectral karyotyping,SKY),染色体涂染,双色荧光原位杂交技术(fluorescence in situ hybridisation,FISH)检测,亚端粒探针F...     

146例胎儿染色体易位核型分析

目的:探讨羊水染色体平衡易位的来源及新生突变。方法:收集8635例羊水标本,应用染色体核型分析技术诊断胎儿是否为染色体易位核型,并分析易位核型的来源。结果:本研究共有146例胎儿染色体易位,其中平衡易位110例,罗伯逊易位36例。110例胎儿染色体相互易位中,57例胎儿染色体易位来自父亲,34例胎儿染色体易位来自母亲,...     

多重荧光原位杂交技术体系的建立及其在检测白血病复杂核型异常中的应用

目的：建立多重荧光原位杂交技术（multiplex fluorescence in situ hybridization，M-FISH）体系，探讨其在检测白血病复杂核型异常中的应用。方法：联合应用常规核型分析、染色体涂抹（chromosome painting，CP）、染色体荧光原位杂交（fluorescence in situ hybridization，FISH）和M-FISH方法分析了两例白血病复杂核型。结果：对其中1例常规核型分析显示为46，XY，der(9)t(9；12)的急性淋巴细胞白血病-L2型病例，M-FISH检出其具有复杂的染色体易位；46；XY，der（2）t(2；9)，der(9)t(9；12；22)。对另1例常规核型难以分析的急性单核细胞白血病-M5型病例，M-FISH检出其复杂核型是46，XY，der(2)t(2；17)，der(10)t(10；11；17)，der(11)t(11；？)。进下不用染色体涂抹和双色FISH证实了M-FISH的结果，并发现MLL基因（mixed lineage leukemia gene）受累。结论：M-FISH是筛选白血病复杂染色体异常的理想方法，对阐明所有白血病、乃至其它肿瘤性疾病和遗传性疾病的染色体易位和基因改变有广阔的应用前景。     

182例有自然流产史夫妇的细胞遗传学研究

目的分析自然流产夫妇的异常核型发生率,探讨自然流产与染色体核型异常之间的关系。方法对182例反复流产夫妇行外周血染色体分析。结果检出异常染色体核型21例,占受检夫妇的11.5%。异常核型中,大Y染色体、平衡易位者例数相等,占异常核型的47.6%,平衡易位者中相互易位8例,罗伯逊易位1例,染色体多态性2例。结论对于不明原因的自然流产夫妇,染色体分析应作为常规的检测方法。     

荧光原位杂交技术在检测染色体异常来源成分中的应用价值

目的探讨荧光原位杂交技术在检测染色体异常来源成分中的应用价值。方法对2例经外周血淋巴细胞培养行染色体核型分析结果不明来源染色体片段异常者,采用亚端粒(subtelomere)探针荧光原位杂交技术进行检测。结果明确诊断了2例染色体片段异常均为染色体相互易位,并鉴定出了易位的片段来源。结论亚端粒探针荧光原位杂交技术可以协助常规G显带染色体核型分析检测出小片段、难以辨认的染色体易位,对协助临床遗传咨询有重要意义。     

染色体涂染技术在恶性血液病研究中的应用

为探讨染色体荧光原位杂交（ＦＩＳＨ）技术在恶性血液病研究中的价值，应用生物素或异硫氰酸荧光素标记的整条染色体涂染探针，对Ｒ带核型分析揭示有难以识别的染色体结构畸变或标记染色体的１０例恶性血液病进行了ＦＩＳＨ检测。通过染色体涂染和核型分析资料的比较，识别了６例标记染色体的来源，确定了４例染色体易位的类型。结果表明：ＦＩＳＨ是一种有效而可靠的检测手段，它大大提高了常规细胞遗传学方法识别标记染色体和其它染色体结构畸变的能力，因而在恶性血液病的染色体研究中值得更多地采用这一新技术。     

重庆地区1020对不良孕产史夫妇的细胞遗传学分析

作者为了研究不良孕产史与染色体异常的关系，采用外周血淋巴细胞常规培养法制备染色体标本，对1020对有不良孕产史的夫妇双方进行了染色体检查，共检出异常核型128例，异常检出率为6．28％，明显高于普通人群。异常核型所涉及的染色体有1、2、3、4、5、6、7、8、9、10、11、12、13、14、15、16、17、18、20、21、X、Y等65种核型。其中4种核型经专家鉴定属世界首报。在异常染色体核型中，平衡易位98例(相互易位68例，罗伯氏易位30例)，占76．56％，染色体臂间倒位16例，占12．50％，其它染色体异常核型12例，占9．38％，嵌合体2例。占1．56％，男性47例。占36．72％；女性81例；占63．28％。并就不良孕产史异常染色体的检出率；染色体平衡易住与不良孕产史；染色体臂间倒位与不良孕产史；大Y染色体与不良孕产史；异常染色体的男女比例等进行了分析和讨论。认为不良孕产史不但与染色体畸变有关，而且与染色体多态性也有一定关系。对于不良孕产史的夫妇进行染色体检查十分必要。这不仅有助于病因的诊断与分析，而且也有助于临床的处理扣指导。     

多重荧光原位杂交结合染色体涂抹技术检测骨髓增生异常综合征复杂核型异常

目的探讨多重荧光原位杂交(multiplex fluorescence in situ hybridization,M-FISH)及全染色体涂抹(whole chromosome painting,WCP)技术在骨髓增生异常综合征(myelodysplastic syndromes,MDS)复杂核型异常检测中的价值。方法对7例常规R显带具有复杂染色体异常的MDS患者应用M-FISH技术确定复杂染色体的重排及标记染色体的组成,识别微小易位。并进一步采用双色WCP技术验证M-FISH检测的结果。结果M-FISH不仅证实了R显带的结果,而且确定了R带核型分析没有确定的6种标记染色体、9种有不明来源的额外物质增加的染色体、5种衍生染色体的组成和来源及4种被忽略的微小易位。涉及17号染色体的异常及-5/5q-是MDS最为常见的两种染色体异常。WCP技术纠正了一些M-FISH漏检及误检的异常。结论M-FISH是明确复杂染色体异常的很有用的分子生物学工具,WCP是M-FISH技术的重要补充,R带核型分析结合分子细胞遗传学工具M-FISH和WCP可以更加准确地描述复杂染色体异常。     

SKY detection of chromosome rearrangements in two cases of tMDS with a complex karyotype

In this study, we used spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH) as complementary techniques for the analysis of two therapy-related secondary myelodysplastic syndrome (t-MDS) cases with complex karyotypes, previously analyzed by G-banding. Different types of SKY's cytogenetic contributions include confirmation of G-banding results, identification of partially characterized rearrangements, identification of marker chromosomes unidentified by G-banding, and detection of cryptic reciprocal translocations. In particular, the ability of SKY to clarify a number of markers led to the comprehension of clonal evolution. The common aberration found in these two t-MDS cases was the fragility of chromosome 5 and monosomy of chromosome 18. We clearly present that the use of SKY combined with conventional G-banding analysis and FISH has assisted in the identification of important chromosomal events that may play a key role in the development of t-MDS.     

Detection of unidentified chromosome abnormalities in human neuroblastoma by spectral karyotyping (SKY)

Spectral karyotyping (SKY) is a novel technique based on the simultaneous hybridization of 24 fluorescently labeled chromosome painting probes. It provides a valuable addition to the investigation of many tumors that can be difficult to define by conventional banding techniques. One such tumor is neuroblastoma, which is often characterized by poor chromosome morphology and complex karyotypes. Ten primary neuroblastoma tumor samples initially analyzed by G-banding were analyzed by SKY. In 8/10 tumors, we were able to obtain additional cytogenetic information. This included the identification of complex rearrangements and material of previously unknown origin. Structurally rearranged chromosomes can be identified even in highly condensed metaphase chromosomes. Following the SKY results, the G-banding findings were reevaluated, and the combination of the two techniques resulted in a more accurate karyotype. This combination allows identification not only of material gained and lost, but also of breakpoints and chromosomal associations. The use of SKY is therefore a powerful tool in the genetic characterization of neuroblastoma and can contribute to a better understanding of the molecular events associated with this tumor.     

分子细胞遗传学技术在确诊9p三体综合征中的应用

目的　用分子细胞遗传学技术鉴别常规细胞遗传学难以确定的染色体异常。方法　用染色体涂染、比较基因组杂交(com parative genom ic hybridization,CGH)和多色显带分析技术(colorbandingchrom osom e analysis,RxFISH),对一例G 显带提示为9 号染色体结构异常的病例进行研究。结果　患儿核型为46,XX,9p ,染色体涂染显示两条9 号染色体(包括短臂额外片段)被均匀涂染,CGH 和RxFISH证实为9 号短臂完全重复,核型准确描述为46,XX,dup 9p(p11→p24∷p24→qter)。结论　这些技术手段可以鉴别常规细胞遗传学难以进行诊断的、复杂的染色体结构异常,在基础及临床医学研究领域中,有着重要的应用前景     

Characterization of complex chromosomal abnormalities in uveal melanoma by fluorescence in situ hybridization, spectral karyotyping, and comparative genomic hybridization

Several nonrandom recurrent chromosomal changes are observed in uveal melanoma. Some of these abnormalities, e.g., loss of chromosome 3, gain of the q arm of chromosome 8, and chromosome 6 abnormalities, are of prognostic value. Cytogenetic analysis and/or fluorescence in situ hybridization (FISH) are used to detect these changes. In some cases, however, detailed cytogenetic analysis is not possible due to the presence of complex abnormalities. To define more accurately these cytogenetic changes, we have applied comparative genomic hybridization (CGH) and/or spectral karyotyping (SKY) to two uveal melanoma cell lines and five primary uveal melanomas, with partially defined and/or complex abnormalities. SKY provided additional information on 34/39 partially defined aberrant chromosomes and revealed a new abnormality, a der(17)t(7;17)(?;q?), that had not been recognized by conventional cytogenetics. Additionally, using SKY, abnormalities involving chromosome 6 or 8 were found to be twice as common as observed with cytogenetic analysis. CGH was especially useful in assigning the abnormalities identified by SKY to specific chromosomal regions and, in addition, resulted in the detection of a small deletion of chromosome region 3q13 approximately 21. We conclude that SKY and CGH, as methods complementary to cytogenetic and FISH analysis, provide more complete information on the chromosomal abnormalities occurring in uveal melanoma.     

Combined spectral karyotyping and DAPI banding analysis of chromosome abnormalities in myelodysplastic syndrome.

Spectral karyotyping (SKY) is a new molecular cytogenetic technique that allows simultaneous visualization of each chromosome in a different color. We have used SKY for comprehensive analysis of 20 myelodysplastic syndromes (MDSs) (13 primary MDSs, 3 therapy-related MDSs, and 4 acute leukemias developed from MDS, including 1 cell line established from a secondary leukemia), previously analyzed by G-banding. To locate the chromosomal breakpoints, DAPI-counterstained band images from all metaphases were transformed to G-band-like patterns. By using SKY, it was possible to identify the origin and organization of all clonal marker chromosomes (mar), as well as the origin of all abnormalities defined as additional material of unknown origin (add) or homogeneously staining regions (hsr) by G-banding. In total, SKY identified the chromosomal basis of 38 mar, add, and hsr, corrected 8 abnormalities misidentified by G-banding, and revealed 6 cryptic translocations in 5 cases. Total or partial chromosomal loss (mainly of -5/5q- and -7/7q-) is the most frequent cytogenetic abnormality in MDS. In 3 of 11 cases with -5/5q- and in 4 of 8 with -7/7q-, lost material was detected by SKY in unbalanced translocations. A total of 60 chromosomal losses were identified by G-banding in 16 cases with multiple chromosome abnormalities involving at least 3 chromosomes. For 26 of these losses (43%), SKY analysis suggested that the losses were not complete, but had been translocated to a variety of partner chromosomes. Moreover, SKY analysis revealed that a ring chromosome in a case of acute leukemia developed from MDS contained three to six segments that originated from chromosome 21 material. Fluorescence in situ hybridization showed the amplification of the AML1 gene on regions derived from chromosome 21, providing the first evidence of amplification involving this gene in MDS. Genes Chromosomes Cancer 26:336-345, 1999.     

Characterization of chromosomal aberrations in a case of glioblastoma multiforme combining cytogenetic and molecular cytogenetic techniques

A case of glioblastoma multiforme (GBM) that was investigated with a broad spectrum of cytogenetic and molecular cytogenetic techniques is reported. The results of cytogenetic studies, interphase fluorescence in situ hybridization, comparative genomic hybridization, and spectral karyotyping (SKY) are reported. Various structural chromosomal aberrations were identified, among which aberrations involving chromosome arm 2p were especially frequent. Using SKY, six translocations not previously described in GBM are reported.     

Assessment of molecular cytogenetic methods for the detection of chromosomal abnormalities

Some marker chromosomes and chromosome rearrangements are difficult to identify using G-bands by Giemsa staining after trypsin treatment (G-banding) alone. Molecular cytogenetic techniques, such as spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH), can help to detect chromosomal aberrations precisely. We analyzed the karyotypes in 6 cases of multiple congenital abnormalities and 1 case of spontaneous abortion (case 2). Three cases (cases 1, 6, and 7) had marker chromosomes, and 4 cases (cases 2-5) had chromosomal rearrangements. The karyotypes in cases 1, 2, and 3 were determined using FISH with probes based on the clinical findings and family histories. Spectral karyotyping (SKY) analysis in cases 4-7 showed that this method is useful and saves time. The combination of SKY and FISH analyses defined the range of the ring chromosome in case 7. We demonstrated that a combination of G-banding, FISH, and SKY can be applied effectively to the investigation of chromosomal rearrangement and to the detection of marker chromosome origins. We suggest the use of these methods for prenatal diagnosis, in which the inherent time limitations are particularly important.     

光谱核型分析技术在染色体异常诊断中的应用

目的建立稳定的光谱核型分析技术,并评价其在染色体异常诊断中的应用价值。方法应用光谱核型分析技术对16例外周血和1例羊水细胞染色体样本进行诊断,并与G-显带诊断结果进行比较。结果所建立的光谱核型分析技术不但成功地对全部15例G-显带诊断结果为正常或平衡易位的样本进行了正确诊断,而且对G-显带无法识别的1例外周血样本的衍生染色体片段和1例羊水样本的标记染色体亦明确了来源。结论光谱核型分析技术对染色体异常的诊断具有很高的敏感性和特异性,并且在明确传统核型分析技术不能分析的标记染色体或衍生染色体片段的来源方面具有重要应用价值。     

Acute leukemia cytogenetics: an evaluation of combining G-band karyotyping with multi-color spectral karyotyping

We have, during a 12-month period, evaluated the adjuvant effect of combining G-band karyotyping and multi-color spectral karyotyping (SKY) in acute leukemia patients. Forty-four cases were evaluated; fewer cases than those routinely analyzed by G-band cytogenetics had mitoses left for SKY analysis. Of the 44 patients, 35 were acute myeloid leukemia (AML) and 9 acute lymphatic leukemia (ALL) cases. Twenty-seven of 35 AML and 7 of 9 ALL patients had an abnormal G-band karyotype. Thirteen of these 34 abnormal cases had a simple clonal chromosome aberration, and the remaining 21 cases had a complex karyotype. The SKY confirmed the simple karyotype in 11 and in 7 with a complex karyotype. In 13 of the cases with a complex karyotype, ambiguous structural aberrations were classified, in 6 of these, SKY disclosed cryptic translocations. Thus, SKY either extended or confirmed G-band karyotypes in 31 of 34 analyzed abnormal cases. Cases where SKY did not reveal the abnormal clone showed only few abnormal mitoses by G-banding (2/23, 2/25, and 4/27). Additional or confirmatory information was therefore obtained in 91% of analyzed cases, and SKY proved to be a valuable additional tool for hematologic cytogenetics.     

Telomeric fusion as a mechanism for the loss of 1p in meningioma

Characteristic cytogenetic aberrations are found in the various histopathological designations of meningioma. These aberrations range from the loss of 22q in histologically benign tumors to complex hypodiploid karyotypes in atypical and malignant tumors. This progression is characterized by increasing chromosome loss and instability, with a critical step being the loss of 1p. We report a detailed cytogenetic investigation of chromosome aberrations in a series of 88 meningiomas using Giemsa banding and multicolor spectral karyotyping (SKY). Clonal chromosome aberrations were identified in 46 (52%) tumors by G banding. Thirty-five tumors showing complex chromosome aberrations not fully characterized by G banding were subsequently reanalyzed by SKY. The SKY technique refined the G-band findings in 18 (51%) of the tumors on which it was applied. The most common features of cytogenetic progression in the complex karyotypes were chromosome arm-specific losses relating to the formation of deletions and dicentric chromosomes involving 1p. Part or all of 1p was lost in 19 tumors. Five tumors showed evidence for the loss of 1p in a progressive step-wise series of telomeric fusions involving the formation of unstable intermediates. Five recurring dicentric chromosomes were identified, including dic (1;11)(p11;p11), dic(1;12)(p12 approximately p13;p11), dic(1;22)(p11;q12 approximately q13), dic(7;19)(p11;p11), and dic(19;22)(p11 approximately p13;q11 approximately q13). These findings provide evidence that telomeric fusions play a role in the formation of clonal deletions, dicentrics, and unbalanced translocations of 1p. The loss of 1p has possible diagnostic and prognostic implications in the management of meningioma.