中山市黄圃地区92例地中海贫血患者基因型分析

目的了解中山市黄圃地区地中海贫血患者基因型构成,为中山市地中海贫血的产前诊断、遗传咨询和预防计划提供有价值的资料。结论抽取92例经血红蛋白电泳筛查并经临床诊断为地中海贫血的患者静脉血,用Gap-PCR方法检测α地中海贫血患者3种常见基因缺失和用PCR结合反向斑点杂交法检测β地中海贫血患者17个常见基因突变位点。结果对92例地中海贫血患者进行基因检测,检测出α地中海贫血60例（65.2%）,β地中海贫血32例（34.8%）,其中60例α地中海贫血患者3种基因缺失中,检测出-SEA54例（71.1%）、-α3.715例（19.7%）、-α4.27例（9.2%）,其基因型以-SEA/αα最常见（63.2%）。32例β地中海贫血患者基因突变位点CD41-4210例（31.4%）、CD177例（21.9%）、IVS-Ⅱ-6547例（21.9%）、-282例（6.3%）、CD432例（6.3%）、CD71-721例（3.1%）、βE1例（3.1%）。结论中山市黄圃地区地中海贫血患者基因型中α地中海贫血患者以-SEA/αα基因型最为常见,β地中海贫血患者基因突变位点以CD41-42点突变最为常见,为本地区开展产前诊断和遗传咨询提供了参考资料。     

毛细管电泳技术在新生儿静止型α地中海贫血筛查中的应用

目的探讨基于滤纸干血斑的毛细管血红蛋白电泳技术在新生儿静止型α地中海贫血筛查中的临床应用。方法回顾性分析222例地中海贫血产前诊断结果为静止型α地中海贫血的基因类型及其对应新生儿滤纸干血斑毛细管血红蛋白电泳结果。采用跨越断裂点PCR及PCR-反向点杂交检测α地中海贫血常见的3种缺失突变和3种点突变。新生儿滤纸干血斑采用毛细管电泳技术进行血红蛋白电泳。结果各组静止型α地中海贫血Hb Bart's含量有差别(H=73.78,P0.001),除α~(WS)α/αα组外,突变型α地中海贫血Hb Bart's含量高于缺失型α地中海贫血(P0.05);5组静止型α地中海贫血检出率差异具有统计学意义(P0.001),其中α~(WS)α/αα组未检出,αCSα/αα组检出率最高(96.34%),突变型α地中海贫血检出率高于缺失型α地中海贫血(P0.05)。结论毛细管电泳技术可通过检测滤纸干血斑Hb Bart's进行新生儿点突变的静止型α地中海贫血筛查。     

基于片段长度差异应用HPLC快速检测β-地中海贫血

目的 通过高效液相色谱检测β-地中海贫血常见的基因型.方法 通过多重引物延伸反应同时扩增β-地中海贫血常见的突变位点,基于长度区分不同位点野生型引物和突变型引物扩增产物,并将待检品与标准品检测结果 进行对比,以辨别待检样本的基因型.结果 建立了稳定的高效液相色谱检测点突变技术平台,实现了对β-地中海贫血常见基因型的快速检测,通过对质粒样本、临床病例样本的验证,完全符合质粒样本测序、患者基因组检测的结果.结论 高效液相色谱检测β-地中海贫血具有快速、简便、样品量少等优点,其为遗传病点突变提供了新的检测手段.     

应用PCR技术对β地贫症进行基因诊断

本文应用DNA体外多聚酶链反应基因扩增新技术,结合斑点杂交,检测基因点突变的直接、快速、简便方法,对4例受试者进行了β地中海贫血症的基因分析和产前基因诊断。     

4411例新生儿血红蛋白毛细管电泳地中海贫血筛查的探讨

目的探讨新生儿血红蛋白毛细管电泳地中海贫血筛查的应用价值。方法对采用毛细管血红蛋白电泳筛查新生儿地中海贫血资料进行回顾性总结。结果4411例新生儿血红蛋白毛细管电泳筛查,检出异常血红蛋白523例,阳性率11．89％,其中,检出d地中海贫血473例（其中HbBart’s胎儿水肿综合症1例,出生时已死亡：HbBart’s含量〈70％为467例;HbCS5例）,阳性率10．72％。β-地中海贫血15例（HbE杂合子15例）,阳性率0．34％。检出异常血红蛋白病（即HbD和HbJ杂合子）35例,阳性率0．79％。结论新生儿脐血红蛋白毛细管电泳地中海贫血筛查主要以d为地中海贫血主,β-地中海贫血很难筛查,除非出现HbE带,筛查阳性者建议做地贫基因检测或DNA序列测序分析。     

基因测序确认一例新β地中海贫血基因突变CD112（T→A）

目的 报道1例中国人少见的β地中海贫血基因突变CD112（T→A）／N。方法 根据血常规平均红细胞体积（MCV）和平均血红蛋白含量（MCH）以及血红蛋白电泳的HbF和HbA2对婚检和产检患者筛查地中海贫血，对可疑β地中海贫血患者采用基因扩增反向点杂交法检测常见17个位点突变。对于未发现突变者采用基因测序。结果 患者携带一种中国人少见的B地贫基因突变CD112（T→A）。结论 β地贫基因CD112（T→A）突变的报道丰富了中国人β地贫突变谱。对于指导婚检、产检、遗传咨询具有重要价值。     

单细胞水平β地中海贫血基因突变检测技术的实验研究

目的探讨在单个淋巴细胞水平能否同时检测β地中海贫血多个突变.方法将我国β地中海贫血常见8种突变点(CD41-42、IVS-Ⅱ-654、CD17、TATA box nt -28、CD71-72、TATA box nt -29、CD26、IVS-Ⅰ-5)的等位特异性寡核苷酸(allele specific oligonucleiotide,ASO)探针点样于尼龙膜上,制备β地中海贫血常见突变诊断膜条.应用蛋白酶裂解法处理单个细胞,采用15个碱基的随机引物对单个细胞的基因组进行引物延伸预扩增(primer extension preamplification,PEP),取其产物5μl分别对β地中海贫血的目的基因片段进行巢式或半巢式PCR扩增与生物素标记,然后采用β地中海贫血常见突变诊断膜条与标记产物进行反向斑点杂交(reverse dot blot,RDB)检测β地中海贫血突变型.结果使用显微操作法分别从1例正常女性及4例β地中海贫血血标本中获得3个淋巴细胞.采用Rechitsky等的蛋白酶K裂解法处理单个淋巴细胞,扩增效率为93.3%,等位基因脱扣率为6.7%.RDB杂交后结果显示与预料的相符,其基因型依次为N/N、CD17(A→T)/N、IVS-Ⅱ-654(C→T)/CD17(A→T)、CD41-42(-CTTT)/N、TATA box nt -28(A→G)/N.结论在单细胞水平应用PEP及RDB技术可以同时检测β地中海贫血多个突变,操作相对简便,为胚胎植入前遗传学诊断和无创性产前诊断的应用提供了新的检测方法,有较好的临床应用前景.     

全自动毛细管血红蛋白电泳在地中海贫血筛查中的作用

目的探讨全自动毛细管血红蛋白电泳在地中海贫血筛查中的作用。方法对我院送检1605份患者标本应用法国Sebia毛细管电泳分析系统进行血红蛋白电泳检测地中海贫血,通过自动扫描系统分析,检测血红蛋白（Hb）各组分的含量。结果在送检的1605例标本中,应用全自动血红蛋白电泳检出α地中海贫血表型阳性181例,阳性率为11.21%;β地中海贫血表型阳性224例,阳性率为13.96%;α、β混合地中海贫血6例,阳性率0.37%;其他血红蛋白病17例,阳性率1.06%。结论全自动毛细管血红蛋白电泳电泳区带清晰,扫描定量准确,可以定量检测HbA,HbF,HbA2的含量。可以将地中海贫血初步分类为α地中海贫血或β地中海贫血,有效地筛查出高危患者,为地中海贫血的诊断提供重要依据。     

广东省惠州地区620例地中海贫血基因检测分析

目的调查广东省惠州地区地中海贫血的基因突变类型及特征,为本地区地中海贫血的遗传咨询及产前诊断提供数据。方法采用PCR+导流杂交法对1588例疑似地中海地贫患者进行3种缺失型(--~(SEA)、-α~(3.7)、-α~(4.2))和3种非缺失型突变(α~(CS)α、α~(QS)α、α~(WS)α),及常见16种β地贫基因突变类型检测。对常规基因型检测仍无法确诊者,采用多重链接探针扩增技术、DNA测序、缺口PCR及血红蛋白持续增多症缺失型电泳等技术进行罕见β地中海贫血基因检测。结果1588名疑诊患者中共检出地中海贫血患者620例,其中α-地中海贫血占24.55%(390/1588)。β-地中海贫血占14.48%(230/1588),检出6例罕见缺失型β地中海贫血,阳性率为2.61%(6/230)。结论惠州地区是地中海贫血的高发区,应积极开展地中海贫血的防治工作,还应注意罕见地贫的筛查和诊断,明确基因型,给临床提供确切的诊断依据。     

湖州地区孕妇β-地中海贫血基因类型及构成分析

目的了解浙江省湖州地区孕妇β-地中海贫血基因携带率及基因类型分布,为遗传咨询提供参考,提高人群优生质量。方法对2015年9月到2016年8月来我院早孕检查孕妇进行地中海贫血筛查,应用红细胞参数分析与血红蛋白成分分析联合筛查;筛查阳性孕妇采用"多色荧光PCR熔解曲线(MMCA)"技术进行β-地中海贫血基因检测。结果浙江省湖州地区孕妇β-地中海贫血表型阳性率1.26%(186/14 411),基因携带率为0.85%;154例β-地中海贫血表型阳性进行β-地中海贫血基因检测,101例携带β-地中海贫血基因,阳性检出率为65.6%(101/154);共检测出突变基因9种,其中β0突变(IVS-Ⅱ-654、CD17、CD41-42、-28、CD71-72)5种,β+突变(CD26、CD27-28、-73、-90)4种;101例携带β-地中海贫血基因孕妇均为杂合突变,所占比例较高的基因型为:βIVS-Ⅱ-654/βN(30.7%)、βCD17/βN(24.8%)、βCD41-42/βN(19.8%)和β-28/βN(13.9%);β0和β+两组地中海贫血孕妇血液学参数比较,血红蛋白(Hb)、平均血红蛋白体积(MCV)、平均血红蛋白含量(MCH)、红细胞分布宽度(RDW)有显著性差异,血红蛋白A2(HbA2)无显著性差异。结论湖州市孕妇人群β-地中海贫血基因携带率略高于全国平均水平,基因型突变类型多样,突变谱有地区差异;联合筛查对β-地中海贫血产前筛查有一定的社会经济效益;本研究对β-地中海贫血遗传咨询和产前诊断提供数据支持。     

Rapid detection of low-abundance K-ras mutation in stools of colorectal cancer patients using chip-based temperature gradient capillary electrophoresis

Mutant K-ras provides an independent negative predictive marker for epidermal growth factor receptor (EGFR)-targeted therapy in colorectal cancers (CRCs). Rapid, sensitive, and cost-effective screening for K-ras status will overarch rational personalized medicine. Stool-based DNA testing offers unique advantages for CRC screening such as noninvasiveness, high specificity, and patient compliance, whereas complicated procedures and the low sensitivity of the present approaches have hampered its application on a wide scale. In this study, a chip-based temperature gradient capillary electrophoresis (TGCE) technique was applied to detect low-abundance K-ras mutations under a pooled experiment and analyze K-ras mutations in 30 paired stool samples and cancer tissues of CRC patients and 15 stool samples of healthy volunteers. The chip-based TGCE results showed that the successful analysis of K-ras status could be achieved within 6?min with an extremely low sample consumption of 14?nl. Detection is sensitive enough to reliably report 0.2% mutant CRC cells in a wild-type background, and 0.5?ng of template DNA was sufficient for chip-based TGCE. Of the 30 stool samples of CRC patients analyzed, 17 (57%) harbored K-ras mutations, and the lowest percentage of the detectable mutant K-ras in stool samples was 2%. The coincidence rate for K-ras mutations between stools and tissues obtained by the chip-based method reached 97% (29/30). One of the 15 stool samples of normal controls carried K-ras mutations, producing a specificity of 93%. Clone sequencing data entirely confirmed the results obtained by chip-based TGCE. The study demonstrates that chip-based TGCE is capable of rapidly screening low-abundance K-ras mutations with high sensitivity, reproducibility, simplicity, and significant savings of time and sample. Application of this method to genotype the K-ras gene in stools would provide a potential means for predicting the effectiveness of EGFR-targeted therapy in CRC patients using noninvasive approaches.     

K-ras point mutations in routinely processed tissues: non-radioactive screening by single strand conformational polymorphism analysis.

AIMS--To develop a non-radioactive method to screen routinely fixed, paraffin wax embedded specimens for the occurrence of point mutations; to evaluate the single strand conformational polymorphism (SSCP) analysis technique for the detection of K-ras point mutations as a result of electrophoretic mobility shifts. METHODS--DNA was extracted from archival specimens of colon cancer and from established colon cancer cell lines with known point mutations. A K-ras gene fragment containing codons 12 and 13 of exon 1 was amplified with the polymerase chain reaction (PCR). Denatured DNA fragments were run on 10% polyacrylamide gels under non-denaturing conditions. After electrophoresis DNA was blotted and the single stranded DNA was detected using a digoxigenin labelled ras probe. The nature of the detected point mutations was identified and confirmed by sequencing and hybridisation with oligonucleotides using 32P labelling. RESULTS--Wild type and aberrant alleles were detected caused by mobility shifts after electrophoresis of the PCR products. Commonly occurring mutations in the K-ras gene--in the first two positions of codon 12--could easily be detected in DNA from archival paraffin wax embedded colon cancer tissue. In all the colon tumour samples studied wild type gene alleles were also found, presumably derived from normal cells in the specimen. CONCLUSIONS--The SSCP method permits rapid non-radioactive screening of adenomas or carcinomas for the occurrence of point mutations in the K-ras gene. But if a mutation is detected by an electrophoretic mobility shift, its identification requires confirmation by sequencing or oligonucleotide hybridisation.     

High-throughput single-strand conformation polymorphism analysis by automated capillary electrophoresis: robust multiplex analysis and pattern-based identification of allelic variants

Genetic diagnosis of an inherited disease or cancer often involves analysis for unknown point mutations in several genes; therefore, rapid and automated techniques that can process a large number of samples are needed. We describe a method for high-throughput single-strand conformation polymorphism (SSCP) analysis using automated capillary electrophoresis. The operating temperature of a commercially available capillary electrophoresis instrument (ABI PRISM 310) was expanded by installation of a cheap in-house designed cooling system, thereby allowing us to perform automated SSCP analysis at 14-45 degrees C. We have used the method for detection of point mutations associated with the inherited cardiac disorders long QT syndrome (LQTS) and hypertrophic cardiomyopathy (HCM). The sensitivity of the method was 100% when 34 different point mutations were analyzed, including two previously unpublished LQTS-associated mutations (F157C in KVLQT1 and G572R in HERG), as well as eight novel normal variants in HERG and MYH7. The analyzed polymerase chain reaction (PCR) fragments ranged in size from 166 to 1,223 bp. Seventeen different sequence contexts were analyzed. Three different electrophoresis temperatures were used to obtain 100% sensitivity. Two mutants could not be detected at temperatures greater than 20 degrees C. The method has a high resolution and good reproducibility and is very robust, making multiplex SSCP analysis and pattern-based identification of known allelic variants as single nucleotide polymorphisms (SNPs) possible. These possibilities, combined with automation and short analysis time, make the method suitable for high-throughput tasks, such as genetic screening.     

引物延伸变性高效液相色谱产前诊断β-地中海贫血

目的建立针对中国人常见β-地中海贫血(β-地贫)基因型的产前诊断新方法。方法PCR扩增的靶序列,经引物延伸,得到中国人β-地贫5个常见突变的特异性延伸片段,用全变性高效液相色谱分析延伸片段混合物,分离图谱可鉴定被检样本的基因型。结果盲法分析显示,36个家系108例样品的引物延伸变性高效液相色谱与反向点杂交(reversedotblot,RDB)检测结果符合率为100%。其中6例RDB诊断为上述5个常见突变以外的突变。该法的突变检出率为94.4%(102/108),对产前诊断家庭的诊断率为97.2%(35/36)。结论该法是一种准确、高效的β-地贫突变分析方法,可用于β-地贫的产前诊断。     

一个β地中海贫血复合δβ地中海贫血家系的表型与基因型分析

目的：调查一种缺失型δβ地中海贫血（简称地贫）基因型与表型的关系,探索进行β地贫复合该缺失型突变高风险胎儿的快速产前诊断方法。方法：以表型和基因分型进行家系分析。表型分析采用红细胞指标和血红蛋白电泳分析;用跨越断裂点的三引物聚合酶链反应直接分析法检测δβ地贫缺失突变;用反向点杂交技术筛查β地贫基因突变;并对一例该型地贫高风险胎儿进行了产前基因诊断。结果：先证者（重症地贫）为一种缺失型δβ地贫与β地贫双重杂合子,其δβ地贫基因遗传自母方,在该家系3代9名成员中共检测到4例携带了这一基因,其表型和基因型结果相互吻合;β地贫基因（密码子41－42－CTTT移码突变）遗传自父方。对该家系的重症地贫高风险胎儿进行产前基因诊断的结果显示,胎儿的基因型完全正常。结论：在国内首次报告由缺失型δβ地贫基因与β地贫移码突变双重杂合导致的重平地贫高风险胎儿的产前诊断结果。采用的技术简便、快速,可用作同类事件的参考。     

Detection of salmonellae in chicken feces by a combination of tetrathionate broth enrichment, capillary PCR, and capillary gel electrophoresis

This report describes a rapid detection procedure for salmonellae from chicken feces by the combination of tetrathionate primary enrichment (preenrichment [PE])-bacterial lysis-capillary PCR and capillary gel electrophoresis. Pure Salmonella enterica serovar Enteritidis 64K was reisolated and detected by capillary PCR after buffered peptone water and nutrient broth, tetrathionate broth base Hajna (TTBH), and tetrathionate broth (TTB) preenrichments. When the same culture was mixed with intestinal homogenate, bacteriological reisolation and capillary PCR detection was achieved only by TTBH and TTB preenrichments. Capillary gel electrophoresis revealed that a Salmonella genus-specific 281-bp PCR product was detected when Salmonella strains but not non-Salmonella strains were tested. The detection limit of capillary PCR with whole-cell DNA extracted from pure Salmonella enterica serovars Enteritidis 64K, Typhimurium LT2-CIP60-62, and Gallinarum 64K was 3, 3, and 9 CFU ml(-1), respectively. The detection limit of capillary PCR from whole-cell DNA extracted from intestinal homogenate artificially contaminated with the same three strains was 3, 3, and 7 CFU ml(-1), respectively. We compared the results of the capillary PCR and bacteriological examination from the natural samples. Thirty-five of 53 naturally contaminated samples produced a specific PCR product. In 9 of the 35 PCR-positive samples, Salmonella could not be detected bacteriologically either by PE or a primary and delayed secondary enrichment (DSE) combination. In the 18 PCR-negative samples, 4 samples were found to harbor Salmonella by both PE and DSE and 14 samples were positive after DSE. Fifty-three additional intestinal homogenate samples, which were negative by their PE and DSE in bacteriological examination, were found to be also negative by their PCRs. The total time required to detect Salmonella with the capillary PCR method we used was approximately 20 h. If samples are from clinically diseased birds, the total time for PCR and detection is reduced to 2 h since the 18-h PE is not required. These results indicate that TTB enrichment, bacterial lysis, and genus-specific capillary PCR combined with capillary gel electrophoresis constitute a sensitive and selective procedure which has the potential to rapidly identify Salmonella-infected flocks.     

锁核酸结合分子信标技术检测乙型肝炎病毒DNA G1896A点突变研究

目的研究和评估乙型肝炎病毒（HBV）DNA G1896A点突变的实时荧光PCR检测方法。方法收集经测序验证HBV DNA G1896A未突变的野生型样本150例和已发生突变的突变型样本58例,在突变区域设计分子信标探针,点突变处进行锁核酸处理,利用荧光PCR方法检测HBV前C区G1896A点突变;再从临床标本中随机抽取18例、8例和19例荧光PCR结果分别显示为G1896A突变的标本、杂合的标本以及野生型的标本的PCR产物进行序列测定。结果突变型质粒和野生型质粒的检测灵敏度均可以达到100copies/ml;突变型探针检测高浓度的野生型质粒时无检测信号,野生型探针检测高浓度突变型质粒时无检测信号;突变型模板在总杂合模板中的比例达到5%时则都可以将突变型检测出来;序列测定的8例G1896A突变标本、6例杂合标本和19例野生型标本的PCR产物结果和荧光PCR检测结果完全吻合。结论实时荧光PCR检测方法可以快速、简便、准确地检测HBVDNAG1896A点突变,是检测点突变的重要方法,具有重要的临床应用价值。     

Chip-based TGCE定量检测大肠癌K-ras基因点突变

目的建立一种定量检测大肠癌中K-ras基因突变比例的方法,并分析其与临床病理参数之间的关系。方法利用微流控温度梯度毛细管电泳(Chip-based temperature gradient electrophoresis,Chip-basedTGCE)对4例代表性大肠癌组织切片中的K-ras基因突变进行检测,通过AutoCAD软件计算出K-ras基因突变比例,结果经克隆测序校正后获得线性回归方程。应用该方法定量检测84例石蜡包埋大肠癌组织中的K-ras基因突变比例,并探讨其与临床病理参数的关系。结果 Chip-based TGCE检测K-ras基因突变比例与克隆测序检测K-ras突变比例的线性回归方程为y=0.993x-1.387,K-ras基因突变比例与肿瘤部位和浸润深度有显著相关性(P0.05),检测获得的最低K-ras突变比例达到2.51%。结论该研究显示Chip-based TGCE是一种快速、灵敏、便捷、经济的基因突变比例定量分析方法。     

Performance of the Sebia CAPILLARYS 2 for detection and immunotyping of serum monoclonal paraproteins

We evaluated the performance of the CAPILLARYS 2 (Sebia, Norcross, GA) capillary electrophoresis system for detection and identification of monoclonal proteins in serum samples. We analyzed 104 serum specimens by Sebia Hydragel serum protein electrophoresis (agarose gel electrophoresis [AGE]/immunofixation electrophoresis [IFE]) and CAPILLARYS 2 capillary zone electrophoresis (CZE)/immunosubtraction. AGE and CZE had sensitivities of 90% and 81%, respectively, based on IFE as the "gold standard," and all bands detected were confirmed by IFE (100% specificity). AGE and CZE had an overall agreement of 91% on serum protein electrophoresis. In the population tested, IgG was detected in 29% of samples by IFE and 30% using immunosubtraction. Similarly IgA was detected in 9% of cases by IFE and 8% by immunosubtraction. IgM and light chains were detected in 6% and 3% of cases, respectively, by IFE, whereas CZE/immunosubtraction did not detect any IgM or light chains. In our hands, AGE and CZE had the same specificity for detection of monoclonal proteins; however, CZE/immunosubtraction seems to be less sensitive than IFE for the detection of IgM and, possibly, serum light chains.     

parkin基因的一个新的点突变

目的：研究parkin基因外显子2-10点突变与散发性早发帕金森病发病的关系。方法：应用聚合酶链反应（polymerase chain reaction ，PCR）、琼脂糖电泳、单链构象多态性（single strand conformation polymorphism，SSCP）、DNA测序及限制性核酸内切酶酶切方法，检测了60例散发性早发帕金森病患者以及120名正常人外周血白细胞DNA的parkin基因外显子2-10点突变。结果：发现1例患者的parkin基因外显子2存在纯合突变（G237→C），限制性内切酶酶切证实，其它外显子未见突变，120名正常对照也未见突变。结论：parkin基因外显子存在点突变，可能与部分散发性早发帕金森病发病有关。