应用微阵列一比较基因组杂交检测复发性流产的原因

目的 应用微阵列一比较基因组杂交技术(a CGH),对复发性流产胎儿组织进行基因组染色体微小畸形(CMA)检查,探讨染色体微小畸形与复发性流产的关系。方法 对23例复发性流产胎儿运用Agilent 8×60K DNA芯片筛查染色体拷贝数异常情况,之后查询中国人类染色体异常核型目录数据库,并结合临床资料分析染色体拷贝数异常与复发性流产的关系。结果 14例复发性流产胎儿染色体核型正常;a CGH检测结果表明有9例患者存在不同程度的染色体DNA拷贝数的扩增或缺失,其中2例染色体变异被认为是正常多态性;另外7例染色体区段的变异可能与复发性流产相关。结论 a CGH技术检测染色体的DNA拷贝数的变化,为由DNA拷贝数异常引发的胎儿复发性流产临床诊断提供分子依据,同时为继续追踪下次怀孕提供指导意见。     

应用微阵列比较基因组杂交技术对胎儿复杂染色体易位的产前诊断

目的对产前羊水细胞培养染色体核型分析,检测出染色体易位的胎儿应查父母双方染色体,并用基于芯片的微阵列比较基因组杂交(array comparative genomic hybridization,a CGH)技术检测,以明确其易位染色体的来源及胎儿染色体有无微重复或微缺失,探讨微阵列比较基因组杂交(a CGH)技术在检测胎儿染色体异常中的临床价值。方法通过胎儿羊水细胞培养,染色体G显带核型分析,诊断出胎儿染色体异常,核型为46,X,t(X;13;9)(q13;q14;p22),t(3;6)(p13;q23)。对此例标本进行a CGH分析,通过多位点高分辨率扫描确定胎儿染色体有无微重复或微缺失。结果a CGH扫描检测出胎儿染色体在Xq13.1-q13.2(71,699,190-71,820,393)区带存在121kb的缺失,在13q14.2-q21.1(48,706,590-57,520,639)区带存在8.8Mb的缺失。结论利用a CGH技术可以方便快速地鉴定和分析染色体的微重复或微缺失,结合传统的核型分析技术,可以为判断重复或缺失染色体片段的遗传学效应和产前诊断提供帮助。     

应用多重连接依赖探针扩增技术分析自然流产绒毛染色体异常的研究

目的 探讨多重连接依赖探针扩增(multiplex ligation dependent probe amptification,MLPA)技术在孕早期自然流产绒毛组织染色体分析中的应用.方法 195例自然流产患者留取绒毛组织,包括12例已污染标本,其余183例标本进行绒毛细胞培养及染色体G显带核型分析,同时应用P036和P070试剂盒对195例标本作MLPA分析.结果 183例标本成功培养177例,其中160例(90.4％)采用MLPA技术进行染色体分析的非整倍体结果与G显带染色体核型分析方法的结果一致,包括正常核型65例、所有染色体三体78例、所有染色体单体14例(除1例嵌合体)和不平衡易位3例;G显带核型分析结果异常的15例标本中包括10例多倍体及2例平衡易位,2例9号倒位及1例嵌合体异常MLPA结果显示正常;此外MLPA检测出1例Dup6p;dup6q和1例Dup8p;del 11q,G显带分析结果显示为46,xx和46,xy.结论 MLPA技术对非整倍体异常的检出与经典的染色体核型分析是一致的,同时它能快速的检测出染色体非平衡结构异常以及经典染色体核型分析不能检测的微缺失和微重复,是一种简单、快速且有效的方法,具有临床实际应用价值.     

Array—CGH技术用于产前诊断可疑胎儿染色体异常

目的探讨微阵列比较基因组杂交技术（array—based comparative genomic hybridization,array—CGH）在产前诊断胎儿染色体异常中的应用价值。方法产前诊断发现4例常规G显带染色体核型分析不能明确的胎儿染色体异常,按照标准的array—CGH操作分析对这些病例进行全基因组检测。结果通过array—CGH技术分析,明确了4例胎儿可疑染色体异常的诊断并且进行精确定位,1例染色体部分缺失,1例正常,1例染色体部分重复,1例不平衡易位。结论array—CGH技术对产前诊断胎儿染色体异常具有高分辨率,能够精确定位异常片段,明确胎儿预后,对产前诊断具有重要应用价值。     

微阵列比较基因组杂交技术对一例胎儿染色体复杂易位的产前诊断

目的对1例5条染色体发生复杂易位的胎儿作出产前诊断,评价微阵列比较基因组杂交（array—CGH）技术在产前诊断中的应用价值。方法应用G显带分析羊水细胞染色体及夫妇双方外周血染色体,应用array—CGH技术对羊水细胞进行全基因组高分辨扫描分析,了解是否有微小缺失和重复。结果羊水细胞染色体结果为46,XX,t（5;7;12）,t（14;21）,夫妻双方外周血染色体核型正常,羊水细胞array—CGH结果显示胎儿染色体未发生微缺失或微重复。结论array—CGH技术与传统细胞学技术相结合,大大提升产前诊断技术水平。     

Dandy-Walker综合征与7号染色体微缺失

目的 应用微阵列比较基因组杂交技术探讨Dandy-Walker综合征的遗传学病因.方法 选取8例经产前超声检查提示发生Dandy-Walker畸形且常规G显带染色体核型分析未发现异常的胎儿病例,按照标准的Affymetrix cytogenetic 2.7 M微阵列芯片的操作手册进行杂交、洗涤及全基因组扫描,并应用相应的计算机软件分析结果.结果 微阵列比较基因组杂交技术检测提示3例Dandy-Walker畸形胎儿的染色体7p21.3区DNA拷贝数发生了缺失或重复,异常片段中包含与脊髓小脑疾病相关的NDUFA4和PHF14基因.结论 染色体7p21.3区DNA拷贝数的异常改变是Dandy-Walker综合征的病因之一,其发病机制可能与NDUFA4和PHF14基因的表达异常有关.     

应用单核苷酸多态性-微阵列比较基因组杂交技术检测胎儿标记染色体

目的 探讨单核苷酸多态性-微阵列比较基因组杂交技术(single nucleotide polymorphism arraybased comparative genomic hybridization,SNP-array CGH)检测胎儿标记染色体及其在产前遗传学诊断中的应用.方法 应用SNP-array CGH技术对羊水G显带诊断出的两例携带标记染色体的胎儿(其中胎儿1核型为嵌合体47,XX,+mar[23]/46,XX[16]、胎儿2核型为47,XX,+mar),进行全基因组高分辨率扫描分析,确定标记染色体来源与片段大小;并用染色体末端探针多重连接依赖探针扩增技术(multiplex ligation-dependent probe amplification,MLPA)对胎儿2基因组不平衡进行验证.两例胎儿超声均无明显结构异常;两例胎儿的双亲核型均正常.结果 SNP-array CGH结果显示胎儿1标记染色体来源于9p21.1-p21.3(长度为8.3 Mb),显示嵌合型,根据文献推测此区带的重复携带者可以是表型正常(或有轻微异常)的个体.胎儿2标记染色体来源于15q11.2-q13.3(长度为10.8 Mb),染色体末端探针MLPA检测结果也证实了该重复的存在,此区域基因重复主要引起神经行为方面的异常.告知孕妇及家属风险,均选择终止妊娠.结论 SNP-array CGH技术能比其他技术更精确的确定标记染色体来源,可明确标记染色体的基因型,而且能检测出嵌合型的标记染色体,适用于产前遗传学诊断,并可为产前遗传咨询提供帮助.     

一例心脏缺陷胎儿染色体1p36．3微缺失的产前诊断北大核心CSCD

目的对1例心脏缺陷胎儿进行细胞遗传学诊断,明确其病因,为再生育复发风险评估及产前诊断提供依据。方法应用单核苷酸多态微阵列芯片（single nucleotide polymorphism—based arrays,SNP—array）对胎儿及其父母行全基因组DNA扫描分析,结合G显带核型分析及荧光原位杂交（fluorescence in situ hybridization,FIsH）验证胎儿染色体1p36．3微缺失的来源。结果高密度SNP—array芯片检测显示胎儿在1p36．33p36．23存在6．9Mb的微缺失,G显带核型分析和FISH检测提示其父亲核型为46,XY,t（1;14）（p36．3;p12）,胎儿携带一条由父亲1P末端和14p末端平衡易位形成的1号衍生染色体,核型为46,XY,der（1）t（1;14）（p36．3;p12）pat。结论SNP—array结合G显带和FISH技术有助于发现染色体末端隐匿性易位、微缺失或微重复,提高诊断准确率,对复发风险的评估有重要价值。     

Dandy-Walker综合征胎儿的遗传学分析

目的对1例B超提示为Dandy-Walker畸形的胎儿进行遗传学分析,探讨其染色体DNA拷贝数变异与表型的相关性。方法对1例产前诊断Dandy-Walker综合征胎儿行G显带染色体核型分析、单核苷酸多态性微阵列芯片(single nucleotide polymorphism array,SNP array)及荧光原位杂交(fluorescence in situ hybridization,FISH)检测。胎儿父母行外周血染色体核型分析及FISH检测。结果SNP array分析显示患儿染色体6p25.3p25.1存在4266 kb缺失,FISH验证了SNP array的结果。根据父母外周血FISH结果,确认胎儿父亲为隐匿性t(6;14)(p25.1;p13)携带者,而胎儿遗传了其中一条衍生的6号染色体der(6)t(6;14)(p25.1;p13)。结论成功诊断了Dandy-Walker综合征胎儿的遗传学病因,6p25.3p25.1片段缺失的染色体是由于父亲隐匿性平衡易位产生的不平衡配子所致。     

用比较基因组杂交技术(CGH)检测肾癌染色体畸变

目的应用比较基因组杂交技术(CGH)分析原发性肾癌肿瘤组织中染色体异常变化,探讨肾癌细胞遗传物质的改变,揭示肾癌发生发展的内在本质及其与临床特征之间的关系。方法采用CGH技术对12例肾癌组织提取的全基因组DNA进行检测,以了解肾癌全基因组的变化。结果CGH技术检测的12例肾癌标本中均有染色体的畸变(扩增和/或缺失),常见的扩增区是1p、4p、5q、7p、9p、16p,常见的缺失区是3q、4q、6q、9q、14q、18q。结论原发性肾癌存在广泛的遗传物质不平衡现象,肾癌细胞染色体扩增和/或缺失可能是肾癌发生发展的基础。     

Usefulness of high-resolution comparative genomic hybridization (CGH) for detecting and characterizing constitutional chromosome abnormalities

Comparative genomic hybridization (CGH) is a technique for detection of chromosomal imbalances in a genomic DNA sample. We here report the application of the recently developed method of high-resolution CGH on DNA samples from 66 children having various degrees of delayed psychomotor development with or without clear dysmorphic features and congenital malformations. In 5 of 50 patients with apparently normal karyotypes, a deletion or duplication was revealed by CGH. Only one of these cases had a subtelomeric rearrangement. In one of seven cases with a de novo apparently balanced translocation, deletions were found. In all nine cases where the origin of a marker chromosome or additional chromosomal material was difficult to determine, CGH gave a precise identification. The following findings were from cases having a deletion or duplication as the sole chromosomal imbalance; dup(2)(p16p21), del(4)(q21q21), del(6)(q14q15), del(6)(p12p12), dup(6)(q24qter), and dup(15)(q11q13). One case had dup(9)(p11pter) combined with a very small subtelomeric deletion on 6q. In our hands, CGH is highly useful not only for identifying known chromosomal imbalances, but also for finding elusive deletions or duplications in the large group of children with developmental delay with or without congenital abnormalities. In such cases, the diagnostic yield of CGH appears to be higher than what has been reported from subtelomeric FISH screening.     

5号和18号染色体变异致多发畸形的临床报道和遗传学分析

目的明确一例多发畸形患儿染色体拷贝数变异的性质,分析其染色体变异与表型的相关性。方法首先应用常规G显带分析该例患儿外周血染色体改变,然后应用比较基因组杂交芯片（array comparative genomic hybridization, array CGH ）对该例常规核型分析的结果进行精确定位。结果该患儿常规核型分析为46,XY,inv（9）（p12q13）,Yqh＋。arrayCGH结果为dup（5）（p14．1p15．33）区段（151,737—28,789,424）存在28．64Mb重复;del（18）（q22．1q23）区段（63,993,067—77,982,126）存在13．99Mb缺失。临床表现为面容特殊、眼裂小、牙齿反颌、隐形脊柱裂及脚趾畸形等。结论5号和18号染色体拷贝数变异可导致患儿出现多发畸形;与传统的细胞遗传学分析方法相比,arrayCGH在染色体异常分析中具有更高的分辨率和准确性。     

Comparative genomic hybridization analysis of benign and invasive male breast neoplasms

Comparative genomic hybridization (CGH) analysis was performed for the identification of chromosomal imbalances in two benign gynecomastias and one malignant breast carcinoma derived from patients with male breast disease and compared with cytogenetic analysis in two of the three cases. CGH analysis demonstrated overrepresentation of 8q in all three cases. One case of gynecomastia presented gain of 1p34.3 through pter, 11p14 through q12, and 17p11.2 through qter, and loss of 1q41 through qter and 4q33 through qter. The other gynecomastia presented del(1)(q41) as detected by both cytogenetic and CGH analysis. CGH analysis of the invasive ductal carcinoma confirmed a gain of 17p11.2 through qter previously detected by cytogenetic analysis. These regions showed some similarity in their pattern of imbalance to the chromosomal alterations described in female and male breast cancer.     

Molecular cytogenetic analysis of a nontumorigenic human breast epithelial cell line that eventually turns tumorigenic: Validation of an analytical approach combining karyotyping,comparative genomic hybridization,chromosome painting,and single-locus fluorescence in situ hybridization

The immortalized, nontumorigenic human breast epithelial cell line HMT-3522 has been used as a model for premalignant and, eventually, malignant development. During cultivation, the karyotype evolution was followed. At an early stage, a very long constant phase showed a near-diploid karyotype, with only five marker chromosomes. DNA from this phase was used for comparative genomic hybridization (CGH) analysis, confirming a previously known MYC amplification, and the integration sites were subsequently determined by single-locus fluorescence in situ hybridization (FISH). Furthermore, gains of 5q22-qter and 20q11-qter and deletion of most of chromosome 6 (6p23-qter) were detected by CGH. Because of uncertainty about some of the indicated changes, including a deletion of 1p35-pter, the CGH findings were investigated more closely by chromosome painting, leading to a revision of the karyotype: 45,XX,del(1)(p35),−6,dup(8)(pter→qter::qter→q24),der(12) t(6;12)(p23;p13),der(14)t(5;14)(q22;q32.3),der(17)t(8;17;20)(17pter→17q25::8qter→8q23::8q24→8qter::8q24→8qter::8q23→8q24.1::20q11→20qter). Some karyotypic changes were confirmed by CGH; others had to be revised; and, in the 1p35 region, classical cytogenetics seems superior to CGH. However, CGH revealed a karyotypically unsuspected dup(20q) that might be of special relevance to breast tumor initiation or progression. Our study confirms that CGH is supplementary to current technologies, e.g., karyotyping and Southern analysis, but cannot replace them. In addition, our cell line turned out to be an excellent model for comparison among the different methods. The results imply that future cytogenetic analyses of complex karyotypes should be based on a combination of karyotyping, CGH, and FISH. Genes Chromosom. Cancer 20:30–37, 1997. © 1997 Wiley-Liss, Inc.     

Prenatal detection of cryptic rearrangements by multiplex ligation probe amplification in fetuses with ultrasound abnormalities

PurposeCongenital malformations are a major cause of morbidity and mortality in newborn infants, and genomic imbalances are a significant component of their etiology. The aim of this study was to evaluate the ability of prenatal multiplex ligation probe amplification screening to detect cryptic chromosomal imbalances in fetuses with ultrasound abnormalities of unknown etiology.MethodsMultiplex ligation probe amplification was performed with three separate sets of probes: two for subtelomeric regions and one for mental retardation syndrome loci. Sixty-one fetuses with significant ultrasound anomalies and normal karyotype at a minimum of 400-band resolution were tested between January 2007 and January 2009.ResultsWe identified four unbalanced rearrangements: one del 18pter/amp 5pter, one del 9pter, one 15q11q13 microdeletion, and one 22q11 microdeletion with atypical presentation. After genetic counseling, two of the pregnancies were terminated.ConclusionMultiplex ligation probe amplification analysis was able to identify clinically significant rearrangements in 6.5% of fetuses with prenatally identified sonographic abnormalities. This prospective study highlights that multiplex ligation probe amplification screening of fetuses with ultrasound abnormalities in the prenatal period is technically feasible and relevant for diagnosis and prognosis.     

Tetrasomy 12pter-12p13.31 in a girl with partial Pallister-Killian syndrome phenotype

A dysmorphic patient was shown to carry a small supernumerary marker chromosome. Multicolor, centromere-multicolor and regular FISH experiments proved the marker to be an analphoid 12pter derived isochromosome. Microdissection of the marker followed by reverse painting and array CGH analysis showed that the isochromosome contains approximately 6 Mb of 12pter-12p13.31 derived sequence. This is only the second report of a marker with a neocentromere 12pter and the molecular fine mapping of the duplicated region further refines the 12p region defining the Pallister-Killian syndrome phenotype. In addition, we show the feasibility of using microdissected chromosomes or chromosomal fragments to molecularly map the chromosomal breakpoints on array CGH. This technology may aid in the identification of chromosomal translocation breakpoints.     

Triple structural mosaicism of chromosome 18 in a child with MR/MCA syndrome and abnormal skin pigmentation.

A case of triple mosaicism involving chromosome 18 is described in a girl with abnormal skin pigmentation similar to hypomelanosis of Ito. The karyotype is 46,XX, -18, + del(18)(p11.23-->pter)/46,XX, -18, + idic(18)(p11.23)/46,XX, -18, + r(18). The patient displays some clinical features of monosomy 18p and a few signs of trisomy 18q. Our case illustrates a non-random association of chromosomal mosaicism with abnormal skin pigmentation.     

单核苷酸多态性微阵列和荧光原位杂交技术在Pallister-Killian综合征的产前诊断中的应用CSCD

目的探讨Pallister-Killian综合征（Pallister-Killian syndrome,PKS）的临床特征及遗传学特点,分析Affymetrix CytoScan 750K SNP Array和荧光原位杂志（fluorescence in situ hybridization, FISH）技术在产前诊断中的应用价值。方法对1例36岁孕34＋2周高龄孕妇脐血标本进行G显带染色体核型分析,芯片技术鉴定异常片段来源,运用12pter/12qter探针FISH确认。结果胎儿脐血G显带染色体核型46,XY[77]/47,XY,＋mar[23],出生后新生儿外周血芯片分析结果为arr[hg19] 12p13.33p11.1（173 786～34 835 641）×4,显示12号染色体12p13.33p11.1区段存在34.6 Mb的2次重复;FISH检测显示39%细胞有12号染色体短臂四体。结论通过结合临床特征,综合应用染色体G显带核型分析、FISH技术和芯片技术能准确确认染色体异常片段来源,有效诊断PKS患者。     

Overlapping phenotype of Wolf-Hirschhorn and Beckwith-Wiedemann syndromes in a girl with der(4)t(4;11)(pter;pter)

We report on an 8-month-old girl with a novel unbalanced chromosomal rearrangement, consisting of a terminal deletion of 4p and a paternal duplication of terminal 11p. Each of these is associated with the well-known clinical phenotypes of Wolf-Hirschhorn syndrome (WHS) and Beckwith-Wiedemann syndrome (BWS), respectively. She presented for clinical evaluation of dysmorphic facial features, developmental delay, atrial septal defect (ASD), and left hydronephrosis. High-resolution cytogenetic analysis revealed a normal female karyotype, but subtelomeric fluorescence in situ hybridization (FISH) analysis revealed a der(4)t(4;11)(pter;pter). Both FISH and microarray CGH studies clearly demonstrated that the WHS critical regions 1 and 2 were deleted, and that the BWS imprinted domains (ID) 1 and 2 were duplicated on the der(4). Parental chromosome analysis revealed that the father carried a cryptic balanced t(4;11)(pter;pter). As expected, our patient manifests findings of both WHS (a growth retardation syndrome) and BWS (an overgrowth syndrome). We compare her unique phenotypic features with those that have been reported for both syndromes.