胎儿染色体病的早期筛查

染色体病是由于染色体数目、结构畸变造成基因物质得失所引起的特有的临床表现.常见染色体异常包括数目异常和结构异常.染色体数目异常包括常染色体和性染色体异常.常染色体异常有:21三体、18三体、13三体等这些又被称为非整倍体异常,还有非常罕见的多倍体异常;性染色体异常有:Turner's综合征,性染色体三体异常等.染色体结构异常有染色体缺失﹑易位﹑环状染色体及等臂染色体等.     

新疆地区720例遗传咨询者细胞遗传学分析研究

目的通过对新疆地区720例遗传咨询者的外周血淋巴细胞染色体检查,探讨染色体异常与妊娠胎儿丢失、不孕不育、智力低下、性发育异常、原发闭经等的关系。方法采用外周血淋巴细胞培养方法、常规制备染色体标本,G显带技术进行细胞遗传学分析。结果检出异常核型147例,染色体异常检出率为20.4%。其中,常染色体数目异常29例,常染色体结构异常37例,性染色体异常11例,染色体多态性变异71例。结论染色体异常是造成自然流产、死胎、智力低下、不孕不育、原发闭经等的重要原因。对遗传咨询者进行外周血淋巴细胞染色体检查非常必要,可为产前诊断和优生提供科学依据。     

荆州地区性发育异常患者染色体分析

目的探讨具有性发育异常患者染色体变化的有关特点和意义。方法染色体制备采用淋巴细胞培养或骨髓细胞短期培养法,应用G、C等显带技术,对123例患者进行细胞遗传学分析。结果123例性发育异常患者,检出异常核型36例,异常率为29.27%。结论性染色体异常是导致性发育异常的重要原因之一,对患者进行染色体检查为其性别判断、临床诊治提供依据。     

235例胎儿染色体异常核型分析

目的 分析产前诊断中胎儿染色体异常的检测结果,为胎儿发生染色体异常的遗传咨询积累有价值临床资料.方法 2008年1月至2011年6月,回顾性分析235例胎儿异常细胞遗传学核型.结果235例染色体异常的胎儿中,染色体数目异常103例,其中涉及常染色体三体型、性染色体三体型、整倍体异常、标记染色体和染色体单体型等;染色体结构异常132例,主要涉及罗氏易位、平衡易位、倒位和缺失等;染色体多态性变异32例.结论 对明确有产前高危指征的孕妇分析胎儿染色体核型可为临床诊断提供有力的遗传学参考依据.     

反复流产的原因分析

反复流产一般指一对夫妇发生两次或两次以上流产。导致反复流产的病因有:遗传因素异常、免疫功能异常、内分泌异常、生殖道异常、全身性疾病及感染因素等,现分析如下。 1、遗传因素异常 (1)染色体异常:医学遗传学对大量流产儿进行染色体研究,发现50％-60％流产儿具有染色体异常,它包括染色体数目和结构的异常,常见的数目异常为多倍体、三倍体、单倍体和嵌和体;常见的结构异常主要为染色体易位、断裂、缺失和重复。导致胚胎染色体异常的机理往往是染色     

山东地区413例不孕不育和自然流产患者细胞遗传学分析

目的统计不孕不育和自然流产患者中异常核型的比例,探讨不同异常核型与生殖异常等临床效应之间的关系。方法按常规技术方法制备外周血染色体,经G显带对413例不孕不育和自然流产患者染色体核型进行分析。结果413例病例中28例染色体核型异常,异常检出率为6.78%。其中,相互易位6例;罗伯逊易位1例;染色体多态14例;其它异常7例。结论染色体核型异常是造成流产、死胎、不孕不育以及畸胎的重要因素,对不孕不育和自然流产患者进行细胞遗传学检查具有重要意义。     

荧光原位杂交在恶性血液病中的研究进展

荧光原位杂交(fluorescence in situ hybtidization,FISH)可对分裂中期及间期的细胞进行染色体与基因异常检测,具有直观、快速、敏感性和特异性高以及方便灵活等优点,对白血病、淋巴瘤、多发性骨髓瘤、骨髓增生异常综合征等恶性血液病的诊断、分型、临床治疗选择和预后判断提供重要依据.     

南通地区遗传咨询患儿细胞遗传学分析与临床研究

目的研究遗传咨询患儿中染色体异常核型的发生率。方法本文自2000年1月至2008年2月对174例年龄在14周岁以内的遗传咨询患儿做了外周血淋巴细胞染色体核型分析,通过胰酶消化,G显带,必要时进行C显带检查,显微镜下进行核型分析。结果在因智力低下、性分化异常、身材矮小等前来行遗传咨询的174例患儿中,共检出异常核型61例,异常率35．06％。常染色体结构和数目异常49例,占异常核型的80．33％（49／61）,性染色体结构和数目异常12例,占19．67％（12／61）。男患儿114例,检出异常核型30例,异常率26．32％（30／114）;女患儿60例,异常核型31例,异常率51．67％（31／60）。结论异常染色体是导致智力低下、性发育异常、身材矮小等疾病的重要原因之一,对指导临床诊疗具有重要参考意义,因此染色体检查是十分必要的。     

Y染色体异常对男性生育的影响

目的探讨Y染色体异常的对男性生育的影响。方法常规外周血培养,制备染色体G显带标本,镜下核型分析。结果 542例患者中,检出Y染色体异常14例,主要表现为不良孕史、性别畸形、无精子症等。结论人类Y染色体异常通常会导致男性发育异常或生育异常等遗传效应。     

北京地区78例性染色体异常患者的细胞遗传学分析

目的探讨78例性染色体异常患者的临床表现并进行细胞遗传学分析。方法对患者外周血淋巴细胞行染色体常规G显带核型分析。结果 78例性染色体异常核型中,性染色体数目异常51例,占异常核型的65.38%;性染色体结构异常12例,占15.39%;Y染色体形态异常11例,占14.10%;另外还有性反转综合征4例,占5.13%。结论性染色体异常可导致性分化异常或生殖异常、智力低下等遗传效应,对患者进行染色体的检查,将有助于临床诊断和治疗。     

Rapid detection of non-enterobacteriaceae directly from positive blood culture using fluorescent in situ hybridization

Fluorescent in situ hybridization (FISH) was carried out using two different oligonucleotide probes specific for Pseudomonas spp. and Acinetobacter spp. These probes were tested against different organisms and were found to be highly specific. Sensitivity testing showed that the probes were able to detect as low as 10 3 CFU/mL. In addition, FISH was carried out directly on positive blood culture samples and the detection of microorganisms took less than 2 h. We believe that FISH is a rapid method that can be used as a routine laboratory diagnostic technique for the detection of Acinetobacter spp. and Pseudomonas spp. in clinical samples.     

应用荧光原位杂交技术进行早期难免流产胚胎绒毛细胞染色体检测的研究

目的探讨荧光原位杂交（FISH）技术用于早期难免流产绒毛间期细胞染色体非整倍体异常的临床应用价值。方法采用FISH技术对20例我院住院难免流产病人的流产绒毛进行5条染色体（21、13、18、X和Y）的快速检测。结果被检测的20例样本中,用FISH检测,均获得诊断结果,检测成功率为100%,FISH检测结果中有8例异常,异常率为40%,其中XO是难免流产中胚胎中最多的异常。结论应用FISH技术检测未培养绒毛间期细胞染色体数目异常,具有快速,简便,使用样本量少等优势,具有一定的临床应用价值。     

用荧光原位杂交技术快速诊断100例早期自然流产胚胎染色体数目异常

目的探讨荧光原位杂交(FISH)技术用于诊断绒毛间期细胞染色体数目异常的临床应用价值。方法采用FISH技术对我院100例50-84天的流产绒毛进行7条染色体(13、16、18、21、22、X和Y)的快速检测。同时,将绒毛接种、培养,进行常规细胞染色体核型分析,作为FISH检测结果的对照。结果被检测的100例样本中,用FISH检测,均获得诊断结果,检测成功率为100%,而常规细胞染色体核型分析,则只有91例获得诊断结果,检测成功率为91%。FISH检测结果与常规细胞染色体核型分析结果均相符合。结论应用FISH技术检测未培养绒毛间期细胞染色体数目异常,具有快速,简便,使用样本量少等优势,具有一定的临床应用价值。     

荧光原位杂交技术检测BCR/ABL融合基因的研究

目的建立荧光原位杂交技术平台,应用FISH技术检测在CML检测BCR/ABL融合基因,探讨FISH技术在在CML中应用的价值。方法应用FISH对BCR/ABL探针进行前期的验证,建立正常阈值,再应用该探针检测CML中BCR/ABL融合基因,进行临床检测评估。结果主要假阳性信号模式的正常阈值为1G1R1F 11%、1G1R2F 2%。75例样本FISH检测出48例阳性,15例经细胞遗传学检测,12例检测结果与FISH结果一致,3例CG为阴性,FISH检测为阳性。结论荧光原位杂交技术应用于临床检测之前应进行探针的前期验证,制定一套规范实验流程,且FISH技术在CML诊断、分型、临床治疗方案的制定、预后的判断以及微小残留病变检测上均有重要的价值。     

Amplification and overexpression of HER-2/neu in parotid gland salivary duct carcinoma. Immunohistochemical study and fluorescence in situ hybridization

Salivary duct carcinoma (SDC) is highly malignant salivary gland tumour with aggressive clinical behaviour, characterised by its histological resemblance to invasive ductal carcinoma of the breast. Amplification of gene HER-2/neu and overexpression of its gene product have been shown to have both prognostic and treatment implications in breast cancer. The reports concerning the expression of c-erbB2/HER-2/neu in salivary gland tumours are few and controversial. Thus, eleven cases of SDC were evaluated for HER-2/neu status using immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH). To the best of our knowledge, this is the first molecular genetic analysis of SDCs using FISH. HER-2/neu overexpression, identified as strong membrane staining, was observed in all but one case of SDC in majority of neoplastic cells while only four tumours, of nine cases analysed, revealed HER-2/neu gene amplification by means of FISH analysis. SDCs were associated with poor clinical outcome, 6 patients (55%) died of disseminated carcinoma within 4 to 44 months after therapy. There was no difference in outcome of patients with IHC positive-nonamplified and IHC positive-amplified tumours.     

Reliability of chromogenic in situ hybridization for detecting HER-2 gene status in breast cancer: comparison with fluorescence in situ hybridization and assessment of interobserver reproducibility.

Accurate determination of HER-2 status is important in the management of patients with breast cancer, especially in determining their eligibility for trastuzumab therapy. Fluorescence in situ hybridization (FISH) has been regarded as the gold standard method for detecting HER-2 gene amplification. Recently, chromogenic in situ hybridization (CISH), in which HER-2 is detected by a peroxidase reaction and the gene copies are determined by regular bright-field microscopy, has emerged as a potential alternative to FISH. However, this method requires validation before it can be adopted into clinical practice. In this study, we evaluated 80 cases of invasive breast carcinoma by CISH, compared the results with those obtained by FISH, and assessed interobserver reproducibility among three observers. We found that agreement among the three pathologists on the CISH-determined HER-2 status was achieved in 73 cases (91%), all of which had results matching the corresponding FISH results: 54 nonamplified and 19 amplified. Of the 19 amplified cases, 13 were scored unanimously as high-level amplification; six had a minor scoring discrepancy (ie, low-level vs high-level amplification). A major scoring discrepancy (ie, nonamplification vs amplification) was found in the remaining seven cases, three of which were amplified and four of which were nonamplified by FISH. Two of the latter cases had a polysomy of chromosome 17. The cases that caused scoring difficulty were those with an equivocal or borderline signal number against a high background. Overall, there was nearly perfect agreement between the CISH and corresponding FISH results, and interpretation of CISH results were highly reproducible among the three pathologists. We conclude that, in general, HER-2 status can be reliably assessed by CISH. Confirmatory FISH is recommended in cases with equivocal or borderline CISH copy numbers.     

Culture independent and rapid identification of bacterial pathogens in necrotising fasciitis and streptococcal toxic shock syndrome by fluorescence in situ hybridisation

Fluorescence in situ hybridisation (FISH) targeted to ribosomal RNA is well established for studies in environmental microbiology. Initial applications of this technique in the field of medical microbiology showed that FISH is also a suitable means for the rapid, reliable and cultivation-independent identification of bacterial pathogens. In particular, for infectious diseases that follow a fulminant live-threatening course, such as sepsis or necrotising fasciitis (NF), a fast and reliable detection technique is of great importance. This study describes the development of an rRNA-targeted oligonucleotide set covering more than 95% of the pathogens associated with NF. These probes were tested with a broad collection of target and non-target organisms and found to be highly specific. Subsequently, the FISH approach was applied for the direct detection of bacterial pathogens in clinical samples. Two cases of NF and one case of streptococcal toxic shock syndrome (STSS) were analysed. FISH correctly identified almost all pathogens present in the samples examined within 2–3 h. However, Proteus mirabilis, which was identified in one sample by conventional methods was detected as a rod-shaped bacteria but could not be identified by FISH, since no specific probe was available for this particular organism. In contrast, identification of pathogens in these samples by conventional laboratory methods took 48–72 h. Furthermore, in one patient with pre-sampling antimicrobial therapy bacteria could not be grown from any of the samples. FISH unequivocally revealed the presence of Streptococcus pyogenes in affected tissue samples from this patient. In an experimental setting we demonstrated that FISH readily identifies S. pyogenes cells rendered non-cultivable by antibiotic treatment. Thus, FISH holds great promise for rapid identification of pathogens in fulminant infections such as NF, particularly in cases when pre-sampling antimicrobial therapy hampers culture of the causative agent. Received: 16 December 1999     

Assessment of the HER2 status in breast cancer by fluorescence in situ hybridization: a technical review with interpretive guidelines

Diagnostic assays for HER2 in breast cancer provide important prognostic information and independently help guide management by identifying patients who are the most likely to benefit from Herceptin-targeted therapy. The biological events underlying HER2 -driven breast cancer that can be assessed in routine clinical specimens include the evaluation of gene amplification by fluorescence in situ hybridization (FISH), enhanced messenger RNA expression by real-time polymerase chain reaction, and the assessment of protein overexpression at the tumor cell membrane by immunohistochemistry (IHC). Immunohistochemistry and FISH methodologies have the advantage of being morphologically driven, allowing for correlations between HER2 expression and morphologic features. However, each has important advantages and disadvantages, which are discussed in detail. Although immunohistochemistry is familiar and readily accommodated in most surgical pathology laboratories, increasing demands for FISH testing in the clinical setting will require greater familiarity with the technical aspects of FISH assays and their interpretation by the greater laboratory community. In this review, we provide an overview of FISH testing for HER2 in breast cancer, with an emphasis on technical considerations, interpretive guidelines, scoring criteria, and quality control. The development of automated platforms for hybridization, image analysis for signal enumeration, and experience with FISH interpretation should broaden the availability of this technology for clinical diagnostic testing.     

Real-time PCR quantification of c-erbB-2 gene is an alternative for FISH in the clinical management of breast carcinoma patients

Evaluation of gene amplification and protein expression of the c-erbB-2/neu in breast carcinomas has been an important task in breast cancer management. Although immunohistochemistry is widely applied, fluorescence in situ hybridization (FISH) technology shows its advantage in discriminating tumors in an objective manner. More recently, development of LightCycler technology permits evaluation of gene amplification with a small volume of DNA run in a 20 microL glass capillary. In this study, a series of 87 breast carcinomas were chosen for evaluation of c-erbB-2/neu gene amplification detected by both LightCycler technology and FISH. Real-time polymerase chain reaction (PCR) was performed in LightCycler capillaries with 10 ng sample DNA. By using LightCycler Relative Quantification Software version 1 (LightCycler, Roche, Mannheim, Germany), the amount of c-erbB-2 DNA was calculated as a ratio of c-erbB-2/reference gene quantity in a sample, and then the ratio was divided by the ratio of c-erbB-2 gene/reference gene quantities of a calibrator DNA (a standard DNA provided in the kit), which was run with each sample reaction in parallel. Dual-color FISH was performed on sections of the formalin-fixed, paraffin-embedded tissue array samples using the DAKO HER2 FISH pharmDX kit (DAKO A/S, Glostrup, Danmark) according to the manufacturer's instructions. Furthermore, immunohistochemistry was performed in parallel, with both the NCL-CB11 and HercepTest antibodies. Both the FISH technology and the LightCycler-PCR identified a similar percentage of tumors with c-erbB-2 gene amplification in our present study, 16% (14/87) and 15% (13/87), respectively, whereas immunohistochemistry demonstrated 32% and 34% c-erbB-2 overexpression with the NCL-CB11 and HercepTest antibodies, respectively. In addition, FISH and PCR were highly correlated in detecting tumors mainly with 3+++ c-erbB-2 protein expression by immunohistochemistry, indicating that LightCycler real-time quantification of c-erbB-2 gene may be an alternative to FISH in breast cancer clinical application.