应用长距离PCR技术对60例重型血友病甲进行Ⅷ因子基因倒位的基因诊断

目的对天津60例重型血友病甲(hemophiliaA,HA)患者作出有无FⅧ基因倒位的基因诊断.方法外周血提取DNA,通过长距离PCR(long distance-polymerase chain     

聚合酶链反应技术进展及在优生与遗传产前诊断中的研究现状

聚合酶链反应技术进展及在优生与遗传产前诊断中的研究现状上海第六人民医院妇产病理研究室（２００２３３）刘德莉聚合酶链反应（ｐｏｌｙｍｅｒａｓｅｃｈａｉｎｒｅａｃｔｉｏｎ，ＰＣＲ），又称体外基因扩增或无细胞分子克隆技术。１９８５年问世［１］，１９８９年Ｐ...     

孕妇外周血中胎儿有核红细胞的富集与纯化及其在非侵入性产前诊断中的应用

分子生物学技术已证实孕妇外周血中主要存在 4种胎儿细胞 ,即 :滋养层细胞、粒细胞、淋巴细胞和有核红细胞。最适于富集纯化的是胎儿有核红细胞 (NRBCs)。应用密度梯度离心和流式细胞技术已能分选出该类细胞 ,并成功地应用于产前诊断胎儿性别及非整倍体疾病     

孕妇外周血中胎儿有核红细胞的富集与纯化及其在非侵入性产前诊断中的应用

分子生物学技术已证实孕妇外周血中主要存在4种胎儿细胞,即：滋养层细胞、粒细胞、淋巴细胞和有核红细胞。最适于富集纯化的是胎儿有核红细胞（NRBCs)。应用密度梯度离心和流式细胞技术已能分选出该类细胞,并成功地应用于产前诊断胎儿性别及非整倍体疾病。     

连锁分析在血友病甲基因诊断中的应用

目的综述及讨论近几年以来连锁分析在血友病甲基因诊断中的应用的研究进展,为血友病甲连锁分析位点的选择提供有利的参考。方法以网络数据库资源为主,查询ScienceDirect,pubmed等数据库关于血友病甲连锁分析研究进展等方面的资料。结果共收集到多篇文献,选择其中16篇进行归纳总结与讨论。结论连锁分析现在在世界范围内都应用广泛,对血友病甲携带者的检出与产前诊断不失为一种简便、快捷实用的方法。但是依然有其局限性,比如,有些多态性标记并不能提供诊断信息,对于一些散发病例,连锁分析则不一定有效。对于基因外的多态性标记,细胞减数分裂期间基因重组会导致连锁分析错误。因此,有待发现更多有效的遗传多态性标记用于血友病甲的连锁分析。     

用错配PCR技术直接检测和产前诊断中国人β—地中…

设计了５种对中国人常见β－地贫突变的单碱基错配引物，即在引物的３＇端附近引入一个与模板错配的碱基。用此引物进行多聚酶链式反应，可使扩增产物中创造出能区别正常和突变β－珠蛋白等位基因的限制性酶切位点，藉此人工限制性片段长度多态性即可确诊样品的基因型。用此法分析了４５例β－地贫ＤＮＡ样品，并完成１３个β－地贫高风险胎儿的产前诊断，其结果与ＡＳＯ探针杂交法一致。     

用聚合酶链反应行巨细胞病毒感染产前诊断的研究

对５０例正常育龄妇女、６３例正常孕妇及２０例有异常孕产史的孕妇进行了血清巨细胞病毒抗体ＣＭＶ－ＩｇＧ、ＣＭＶ－ＩｇＭ的检测及聚合酶链反应（ＰＣＲ）的检测，并对正常孕妇及异常孕产史孕妇进行绒毛ＣＭＶＰＣＲ检测。结果正常孕妇血清ＣＭＶＰＣＲ阳性率为３１．７５％，远远高于正常非孕妇的血清ＣＭＶＰＣＲ的阳性率１６％。正常孕妇人流的绒毛ＣＭＶＰＣＲ阳性率为２０．６３％，明显低于有异常孕产史孕妇绒毛ＰＣＲ的阳性率４５％，且异常孕产史孕妇血清ＣＭＶＰＣＲ阳性率明显高于正常孕妇。另对血清ＰＣＲ阳性的１２例早孕时抽取绒毛测ＰＣＲ，阳性率为７５％（９／１２），提示宫内感染率相当高。对正常和异常孕产史孕妇血清ＩｇＭ与ＰＣＲ比较，后者敏感性远超过前者，用ＰＣＲ方法对早孕期ＣＭＶ感染能比较正确地早期作出宫内感染的诊断。     

用聚合酶链反应行为巨细胞病毒感染产前诊断的研究

对５０例正常育龄妇女，６３例正常孕妇及２０例有异常产史的孕妇进行了血清巨细胞病毒抗体ＣＭＶ－ＩｇＧ，ＣＭＶ－ＩｇＭ的检测及聚合酶链反应（ＰＣＲ）的检测，并对正常孕妇及异常孕产史孕妇进行绒毛ＣＭＶＰＣＲ检测，结果正常孕妇血清ＣＭＶＰＣＲ阳性率为３１．７５％，远远高于正常非孕妇的血清ＣＭＶＰＣＲ的阳性率１６％，正常孕妇人流的绒毛ＣＭＶＰＣＲ阳性率为２０．６３％，明显低于有异常孕产史常孕妇绒毛ＰＣＲ的阳     

应用多重PCR和MLPA技术检测DMD患者和携带者的基因突变及产前诊断

目的 应用多重PCR和多重连接依赖探针扩增(multiplex ligation-dependent probe amplification,MLPA)技术检测Duchenne/Becker肌营养不良症(Duchenne/Becker muscular dystrophy,DMD/BMD)患者、携带者并应用于产前诊断.方法 首先采用多重PCR对临床诊断为DMD/BMD的患者检测DMD基因的26个外显子,未查到缺失突变者和可能的携带者采用MLPA检测全部79个外显子是否有缺失或重复突变.对产前诊断病例,用PCR法检测缺失突变,用MLPA法检测重复突变.结果 多重PCR对22例患者的DMD基因的26个外显子检测.13例有缺失突变.未查到常见缺失突变的9例患者经MLPA检测DMD基因的全部79个外显子,3例为重复突变、1例为单个第18外显子缺失、其他5例未查到缺失和重复突变.16例携带者中,3例有家族史,其中2例检出突变;13例为检测到突变的散发病例患儿的母亲,有8例检测到突变.产前诊断9个胎儿(其中双胎1例),2例胎儿有突变,引产后核实无误;7例胎儿未检测到突变,现均已分娩.结论 多重PCR可检出92.86%的缺失突变并可用于缺失突变的产前诊断,因其简便、可靠、价廉可作为临床上DMD/BMD基因诊断的初选.MLPA可用于多重PCR未检测到缺失突变的患者及携带者的检查.     

应用多重PCR和MLPA技术检测DMD患者和携带者的基因突变及产前诊断

目的 应用多重PCR和多重连接依赖探针扩增(multiplex ligation-dependent probe amplification,MLPA)技术检测Duchenne/Becker肌营养不良症(Duchenne/Becker muscular dystrophy,DMD/BMD)患者、携带者并应用于产前诊断.方法 首先采用多重PCR对临床诊断为DMD/BMD的患者检测DMD基因的26个外显子,未查到缺失突变者和可能的携带者采用MLPA检测全部79个外显子是否有缺失或重复突变.对产前诊断病例,用PCR法检测缺失突变,用MLPA法检测重复突变.结果 多重PCR对22例患者的DMD基因的26个外显子检测.13例有缺失突变.未查到常见缺失突变的9例患者经MLPA检测DMD基因的全部79个外显子,3例为重复突变、1例为单个第18外显子缺失、其他5例未查到缺失和重复突变.16例携带者中,3例有家族史,其中2例检出突变;13例为检测到突变的散发病例患儿的母亲,有8例检测到突变.产前诊断9个胎儿(其中双胎1例),2例胎儿有突变,引产后核实无误;7例胎儿未检测到突变,现均已分娩.结论 多重PCR可检出92.86%的缺失突变并可用于缺失突变的产前诊断,因其简便、可靠、价廉可作为临床上DMD/BMD基因诊断的初选.MLPA可用于多重PCR未检测到缺失突变的患者及携带者的检查.     

PCR-构象敏感凝胶电泳技术在血友病A基因分型诊断及携带者检测中的应用

所有的HA家系(含散发)进行直接基因诊断,理论上可筛查新突变并明确其突变类型.该法简便、快速、成本低,在HA直接基因诊断及携带者筛查中优势独特,应具重要应用价值.     

DXS52(St14)在血友病甲基因诊断中的方法改进及应用

目的 改进DXS52(St14)在血友病甲(hemophilia A,HA)基因连锁分析中的实验方法并应用于基因诊断,报道DXS52位点与FⅧ基因发生重组的2个家系.方法 采用PCR和琼脂糖凝胶电泳对61个非倒位HA家系的DXS52位点进行基因检测,并用FⅧ基因内的Bcl Ⅰ、HindⅢ、Xba Ⅰ、STRl、STRl3、STR22和STR24这7个位点以及DXS52位点对这61个家系进行基因连锁分析.结果 DXS52位点在43个HA家系中可提供信息,可诊断率为70.5%(43/61).其中8个家系仅DXS52单个位点能提供信息,占13.1%;两个家系的DXS52与FⅧ基因发生基因重组.结论 采用新的实验条件可使DXS52位点基因检测得到准确清晰的实验结果.该位点可诊断率高,目前是HA连锁基因分析中不可缺少的诊断位点,但该位点位于FⅧ基因外,与FⅧ基因间存在重组可能,单独应用于诊断时应谨慎.

Abstract：

Objective To improve the experimental method of DXS52 (St14) and apply it to genetic testing for hemophilia A (HA). Methods PCR of DXS52 and agarose gel electrophoresis were performed for genetic testing in 61 non-inversion HA families. Linkage analysis of 7 loci within the FⅧ gene including Bcl Ⅰ , Hind Ⅲ, Xba Ⅰ , STR1, STR13, STR22 and STR24 were also carried out for the 61 families.Results DXS52 can provide information in 43 out of 61 families and the diagnostic rate was 70. 5%. Eight families can be diagnosed only by DXS52 locus, accounting for 13. 1%. Two families were found to have recombination between DXS52 and FⅧ. Conclusion The new experimental conditions can reach accurate and clear results in DXS52 genetic testing. This gene maker has high diagnostic rate, so it is an indispensable linkage analysis method in HA gene diagnosis. More caution should be paid when using the extragenic locus DXS52 to perform gene diagnosis because of its high recombinant rate with FⅧ.     

Ethical considerations in medical genetics–the prenatal diagnosis of hemophilia B

A couple is presented who underwent prenatal counseling and amniocentesis for sex determination because the wife was an obligate carrier of hemophilia B. Although the fetus was determined to be male, the parents elected not to have further testing to determine if he had hemophilia or not. The difficulties in the in utero diagnosis of hemophilia B are presented and discussed. In addition, the moral reasoning and decision-making process that this couple went through regarding the decision not to have further fetal testing and to continue the pregnancy is presented and analyzed. These moral decisions appear to be based on family and personal ties, and bonding to the fetus after perception of fetal movement. They combine considerations of the duties and rights involved in such situations, and attend to the anticipated consequences as well.     

F8基因倒位检测及其在甲型血友病基因诊断中的应用

目的建立F8基因第22内含子倒位突变检测新方法,应用于甲型血友病(hemophilia A)基因诊断。方法应用长距离PCR(long distance-polymerase chain reaction,LD-PCR)、倒位PCR(inversion-PCR,IPCR)技术检测31例甲型血友病患者F8基因22内含子倒位;对于倒位突变阳性患者的母亲应用上述两种方法进行携带者诊断;而对倒位携带者孕妇于孕中期抽取羊水,进行产前基因诊断。结果31例甲型血友病患者中查出7例存在倒位突变;4例倒位突变阳性患者的母亲有3例为倒位携带者;对1例倒位携带者孕妇进行了产前诊断,确定其胎儿无倒位突变。结论LD-PCR、I-PCR技术可快速检测F8基因22内含子倒位突变,可应用于患者及携带者基因诊断;I-PCR可用于F8基因22内含子倒位的产前基因诊断。     

How do carriers of hemophilia experience prenatal diagnosis by fetal blood s ampling?

A semistructured personal interview was performed with 29 carriers of hemophilia A or B, 1-4 years after a pregnancy in which prenatal diagnosis (PND) of hemophilia was performed by fetal blood sampling. The carriers had received different recommendations regarding future pregnancies, and 14/29 did not know before they became pregnant that PND by fetal blood sampling was possible. One third of the women felt that important information was lacking in the consultations that preceded the PND. The conclusions regarding future genetic counselling are that more attention should be paid to improving education of all female carriers before a pregnancy, to motivating fathers-to-be to attend counselling sessions with the carriers, and to emphasizing the importance of the emotional support given by the family doctor and by other females who have experienced PND.     

Carrier detection and prenatal diagnosis of X-linked agammaglobulinemia

We investigated the pregnant mother of a boy with X-linked agammaglobulinemia (XLA) but with no family history of immune disease. The X-inactivation pattern was found, using a methylation-sensitive probe, to be skewed in the maternal B cells but random in the polymorphonuclear cells, indicating carrier status and a 50% risk of inheritance for her male fetus. Using probes assigned to regions on either side of the XLA locus and defining RFL polymorphism, we excluded for the first time a diagnosis of XLA on a chorionic villus sample, with a risk of error <0.003. Immunological studies performed at the 19th week of gestation and 3 days after birth confirmed normality. Carrier detection based on the X-chromosome inactivation pattern, together with prenatal studies using probes close to the disease locus, thus permits prenatal diagnosis in families with isolated cases of XLA. © 1992 Wiley-Liss, Inc.     

Hemophilia A: genetic prediction and linkage studies in all available families in Finland

RFLP studies were done in 82 (75%) of all known hemophilia A families in the Finnish population (approximately 5 million). Two intragenic RFLPs (Bc1I/F8A, XbaI/p482.6) and two extragenic markers (TaqI/St14, Bg1II/DX13) were used. Among 263 females at risk, carriership could be evaluated with an intragenic marker in 47% and with an extragenic marker in 26%. In 27% of the females, carriership could be neither excluded nor confirmed; 68% of these females were relatives of an isolated patient. Eight recombinations between the factor VIII gene (F8C) and DXS52 (lod 25.02 at theta max 0.06), eight recombinations between F8C and DXS15 (lod 21.91 at theta max 0.05), and two recombinations between DXS52 and DXS15 (lod 33.56 at theta max 0.01) were found. Using multipoint linkage analysis, the most likely order of loci supported by the data was: F8C-DXS15-DXS52-DXS134. RFLP segregation analysis provides a highly useful method of carrier detection and prenatal diagnosis of hemophilia A, but its limitations must be carefully taken into account.     

Gene-deletion and carrier detections,and prenatal diagnosis of Duchenne muscular dystrophy by analysis of the dystrophin gene amplified by polymerase chain reaction

Polymerase chain reaction (PCR)-based diagnosis was carried out in 62 patients (57 probands) with Duchenne or Becker muscular dystrophy (DMD or BMD) and 226 members in 57 families. The PCR studies were also performed for carrier detection in 57 mothers and 58 sisters, and prenatal diagnosis of 4 fetuses at risk of DMD. The PCR with 7 sets of primers, which amplify 7 different exon-sequences of the dystrophin gene, detected gene deletion of at least one exon in 49% of the probands. The PCR with the other 4 primer sets, which amplify 3 intragenic loci, and subsequent endonuclease digestion detected in 84% of the mothers a heterozygous pattern in at least one such locus/segment. Using the same primer sets, carrier detection was successful in 5 sisters of familial DMD cases, while recombination between the ERT87 and the 3 end intragenic loci was observed in 11% of family members studied. Prenatal diagnosis was made in all the 4 fetuses; two males were affected, one male fetus non-affected, and the remaining one female fetus a carrier. Thus, the PCR study and the primers used in the present study are useful and convincing for rapid diagnosis of DMD and/or BMD.