首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
    
Preimplantation genetic diagnosis (PGD) is an alternative to prenatal diagnosis for couples at risk of transmitting genetic disorders to their offspring. We present a fluorescence in situ hybridization (FISH) analysis of embryos obtained after seven PGD cycles in six couples with Robertsonian translocations and male factor infertility: 4 der(13;14), 1 der(14;21) and 1 der(15;21). Of 74 metaphase II (MII) injected oocytes, 61 (82.4%) fertilized normally and cleaved. Of these, 37/61 (60.7%) embryos were of high morphological quality with ≥6 blastomeres. After biopsy of 44 embryos at day 3 of development, seven degenerated, seven arrested in development and 30/44 (68.2%) evolved, of which 25/30 (83.3%) reached the morula/blastocyst stage. Analysis of biopsied blastomeres showed 23/44 (52.3%) of normal/balanced embryos, of which 15 (11 at the morula/blastocyst stage) were transferred in six cycles. One term pregnancy was achieved, which ended by cesarean section at 37 weeks of gestation, giving birth to two healthy newborn. Analysis of 49 embryos (excluding 12 inconclusive cases) showed a predominance of alternate segregation (38/49, 77.6%) over adjacent segregation (7/49, 14.3%), with one (2%) being a polyploid mosaic and three (6.1%) chaotic. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

2.
3.
    
Fluorescence in situ hybridization (FISH) was performed with probes specific for chromosomes 13, 18, 21, X and Y on 911 of 11123 (8.2%) amniotic fluid samples submitted to the present authors' laboratory for cytogenetic analysis over an 8-year period. Altogether 3516 hybridizations were performed with an interpretable FISH result on all chromosomes requested in 884/911 (97%) of cases. An uninformative FISH result occurred in 44 hybridizations among 27 cases (3%). Of a total of 89 karyotypically proven cases with aneuploidy that might have been detected by FISH, the overall detection rate was 84%. An inconclusive or incomplete FISH result occurred in 9/89 (10%) of these proven aneuploid cases. In the remaining 80 informative proven aneuploid cases, correct detection of aneuploidy was accomplished in 75/80 (94%) of samples. A false-negative result occurred in the remaining 5/80 (6%) of such informative cases. Eighteen cases had karyotypically proven abnormalities that could not have been detected by the targeted FISH. Aside from these 18 cases, FISH allowed correct detection of normal disomy in 785/804 (98%) of such cases. An incomplete FISH result occurred in 18 normal disomic cases. There was a single possible ‘false-positive’ FISH result for chromosome 21. Interphase FISH analysis of uncultured amniotic fluid cells has been shown to be a useful laboratory tool for rapid fetal aneuploidy screening during pregnancy. As with all clinical laboratory diagnostic tests, incomplete or inconclusive results (or even interpretive errors) occur in a small percentage of cases. Nevertheless, FISH results accompanied by other data and by appropriate counseling provide clinicians and patients with valuable information for clinical decision-making surrounding family planning and pregnancy management. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

4.
作为生物除磷系统中的主要功能菌,对聚磷菌菌群进行定性、定量分析是深入理解生物除磷系统、提高除磷效率的必然趋势。目前常用于检测聚磷菌的方法主要有生物化学法和分子生物学法,文章主要阐述了荧光原位杂交技术、聚合酶链反应技术、变性梯度凝胶电泳技术以及多技术结合使用的特点及应用情况,并在此基础上提出了改进措施以及聚磷菌检测技术的发展方向。  相似文献   

5.
    
An Erratum has been published for this article in Prenatal Diagnosis 22 (5) 2002, 451. Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about € 600 and € 4000. In 16 out of 20 centres the parents to be must sign an informed consent form. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

6.
7.
    
We report one case of a familial complex chromosomal rearrangement (CCR) involving four different chromosomes 5, 10, 16 and 18. The CCR was detected prenatally at 20 weeks' gestation because of advanced maternal age and history of recurrent miscarriages. Cytogenetic analysis of cultured amniotic fluid cells with GTG banding showed a 46,XX,t(5;16;10;18)(q13;q22;q11.2;q21) karyotype. Parental cytogenetic study revealed that the mother has the same CCR. RBG banding, high-resolution banding and fluorescence in situ hybridization (FISH) were used to characterize further and confirm the conventional banding data. No physical abnormalities were shown in the targeted fetal ultrasonography examination. The parents decided to continue the pregnancy. The child is now 2 years old and has neither congenital anomalies nor evidence of delayed psychomotor development. The fetal targeted ultrasound and FISH analysis helped us reassure fetal status. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

8.
9.
10.
近年来,有害赤潮于中国沿海频繁发生,对沿海居民身体健康、水产养殖和自然生态形成了潜在的威胁.由于部分有毒赤潮藻在很低的密度下就有可能导致严重的危害,但传统的采样和分析方法无法对这类有毒赤潮进行有效的检测,因而急需发展准确、高效的检测新方法.根据对中国沿海分离的塔玛/链状亚历山大藻(亚洲温带基因型)核糖体大亚基DNA(LSUrDNA)序列信息的分析,设计了两条特异性的荧光标记探针,并建立了针对中国沿海塔玛/链状亚历山大藻复合种(亚洲温带基因型)的荧光原位杂交检测方法.室内模拟实验显示两条探针都能够特异性地标  相似文献   

11.
厌氧颗粒污泥中微生物种群变化的分子生物学解析   总被引:11,自引:0,他引:11  
荧光定量-聚合酶链式反应(RTQ-PCR)与荧光原位杂交(FISH)技术对厌氧反应器内不同状态下颗粒污泥中微生物种群的数量变化与空间分布进行研究.结果发现,颗粒污泥中真细菌明显多于古细菌,但随着厌氧反应器有机负荷的提高,古细菌明显增加,其中产甲烷丝菌也明显增加;真细菌多分布生长在颗粒污泥的外层,而对环境条件敏感的古细菌多分布生长在内层,且随着反应器有机负荷的提高,这种层状分布的特点更为明显.  相似文献   

12.
13.
14.
    
Embryonic aneuploidies may be responsible for pregnancy failure in many IVF patients. In recent years, fluorescent in situ hybridisation (FISH) for multiple chromosomes has been used to document a high frequency of chromosomal errors and aneuploidy in human preimplantation embryos and, after embryo biopsy, to select embryos that are more likely to implant. Such studies suggest that women with recurrent miscarriage and advanced maternal age may benefit most from preimplantation genetic diagnosis with aneuploidy screening (PGD-AS). The success of PGD-AS is likely to be enhanced by new technologies, such as comparative genomic hybridisation, which enable full karyotyping of single cells. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

15.
16.
17.
    
There is increasing interest in the use of preimplantation genetic diagnosis (PGD) as an alternative to routine prenatal diagnosis. However, the costs associated with development and testing of new PGD protocols have forced some PGD centres to limit the number of diseases for which PGD is offered. One of the main factors in the design of new protocols, which affects cost and accuracy, is the choice of the mutation-detection technique. We have assessed the reliability of DNA sequencing and mini-sequencing for clinical diagnosis at the single-cell level and have found them to be rapid and accurate. Extensive optimisation for individual mutations is not usually necessary when employing these versatile techniques and consequently a smaller investment of time and resources should be required during development of new protocols. Additionally, we report single-cell protocols for the diagnoses of cystic fibrosis, sickle cell anaemia and β-thalassaemia, which utilise mini-sequencing. Unlike most mutation-detection techniques, mini-sequencing permits analysis of very small DNA fragments. Small amplicons experience low allele dropout (ADO) rates, and consequently this approach could potentially improve the reliability of PGD. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

18.
    
Preimplantation genetic diagnosis (PGD) was developed more than a decade ago to offer an alternative to prenatal diagnosis for couples at risk of transmitting an inherited disease to their offspring. Portuguese-type familial amyloidotic polyneuropathy (FAP type I), is an autosomal dominant disease presenting an inherited mutation in the gene encoding the plasma protein transthyretin (TTR). We here report the first protocol for single-cell detection of the Met30 mutation in FAP type I and its application to PGD. A nested PCR reaction for exon 2 of the TTR gene was developed. The PCR product was then analysed by restriction enzyme analysis and SSCP allowing the detection of the point mutation. Ten clinical cycles were performed in seven couples. From the 93 metaphase II (MII) injected oocytes, 82 were normally fertilized and 78 were biopsied. A positive signal in the nested PCR reaction was obtained in 61 blastomeres, corresponding to a DNA amplification efficiency of 78.2%. No allele dropout (ADO) or contamination were detected. A biochemical pregnancy was obtained in three cases and a clinical pregnancy in one couple is actually in normal evolution. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

19.
    
Single cell polymerase chain reaction (PCR) for preimplantation genetic diagnosis (PGD) requires high efficiency and accuracy. Allele dropout (ADO), the random amplification failure of one of the two parental alleles, remains the most significant problem in PCR-based PGD testing since it can result in serious misdiagnosis for compound heterozygous or autosomal dominant conditions. A number of different strategies (including the use of lysis buffers to break down the cell and make the DNA accessible) have been employed to combat ADO with varying degrees of success, yet there is still no consensus among PGD centres over which lysis buffer should be used (ESHRE PGD Consortium, 1999 ). To address this issue, PCR amplification of three genes (CFTR, LAMA3 and PKP1) at different chromosomal loci was investigated. Single lymphocytes from individuals heterozygous for mutations within each of the three genes were collected and lysed in either alkaline lysis buffer (ALB) or proteinase K/SDS lysis buffer (PK). PCR amplification efficiencies were comparable between alkaline lysis and proteinase K lysis for PCR products spanning each of the three mutated loci (ΔF508 in CFTR 90% vs 88%; R650X in LAMA3 82% vs 78%; and Y71X in PKP1 91% vs 87%). While there was no appreciable difference between ADO rates between the two lysis buffers for the LAMA3 PCR product (25% vs 26%), there were significant differences in ADO rates between ALB and PK for the CFTR PCR product (0% vs 23%) and the PKP1 PCR product (8% vs 56%). Based on these results, we are currently using ALB in preference to PK/SDS buffer for the lysis of cells in clinical PGD. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

20.
    
We report the prenatal diagnosis of an extra der(4) resulting from 4:2 malsegregation of a maternal balanced complex translocation involving chromosomes 4, 10, and 11. The woman was referred for amniocentesis because of recurrent miscarriages. Fluorescence in situ hybridization was performed in order to characterize the complex chromosome rearrangement. Following genetic counselling, the couple decided to terminate the pregnancy. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号