Rapid prenatal diagnosis of chromosome abnormalities

The aim of the present work was to examine the efficacy of using FISH for the rapid prenatal diagnosis of common chromosome aneuploidies. A total of 100 analyses over a six month period were included in the study. Diagnosis was possible in all cases. A mosaic for trisomy 21 proved, by comparison with an extensive analysis of long term cultures, to be an apparent false positive. Otherwise the technique was reliable, accurate and relatively straightforward to perform. Results could be available within 24 hrs. In most cases an additional long term full analysis was also done, so as to exclude rarer aneuploidies and structural rearrangements. This methodology is seen as a useful addition to the prenatal diagnostic repertoire.     

染色体荧光原位杂交快速产前诊断染色体数目异常

目的探讨产前诊断常见染色体数目异常的技术策略。方法 2010年4月-2012年8月来我院产科门诊进行产前诊断的孕妇,常规穿刺采集羊水或脐带血样本,同时采用常规的染色体核型和荧光原位杂交（fluorescence in situ hybridization,FISH）方法进行检测,比较两种方法的产前诊断结果。结果染色体核型分析报告时间平均为4~5周,494例羊水或脐血样本中有2例分析失败;总染色体异常为8.74%（43/492）;数目异常占异常总数的81.40%（35/43）,结构异常占18.60%（8/43）。在数目异常中,21三体占74.29%（26/35）,18三体17.14%（6/35）,性染色体数目异常8.57%（3/35）。染色体荧光原位杂交报告时间平均为72~96 h;染色体数目异常为7.09%（35/494）,21三体占数目异常的74.29%（26/35）,18三体17.14%（6/35）,性染色体数目异常8.57%（3/35）,对于染色体数目异常的分析结果与核型分析结果一致。FISH未能检出染色体结构异常。结论针对常见的染色体数目异常（21三体、18三体、13三体、性染色体单体或三体）,FISH可直接进行产前诊断;FISH联合染色体核型分析是较全面了解染色体畸形的产前诊断技术策略。     

Rapid genetic diagnosis and prenatal diagnosis of spinal muscular atrophy by denaturing high-performance liquid chromatography

Spinal muscular atrophy （SMA） is a common Pautosomal recessive neuromuscular disorder （1in 6000 to 10 000 births） caused by mutations in the SMN1 gene at 5q13. More than 90%-98% of SMA patients show homozygous deletion of SMN1, which has proved to be useful in the diagnosis of SMA. But it is hampered because of the existence of a highly homologous gene, SMN2. Based on nucleotide mismatches between SMN1 and SMN2, the following two DNA tests are usually performed： single-strand conformational polymorphism （SSCP） and polymerase chain reaction （PCR） followed by a restriction enzyme digestion.In this study we developed a new method for rapid genetic diagnosis of SMA by denaturing high-performance liquid chromatography （DHPLC）, which is based on different retention of homoduplexes and heteroduplexes in detecting the homozygous deletion of SMN1. Both genetic and prenatal diagnoses were performed successfully for a SMA family by DHPLC, which was confirmed as a rapid and effective technique for detecting the deletion of SMN1.     

Rapid prenatal diagnosis of trisomy 21 by fluorescent quantitative multiplex polymerase chain reaction

Trisomy 21, also named Down syndrome was the most frequent autosomal aneuploidy and the most common cause of mental retardation. Fifty percent patients had congenital heart malformation. Every 20 minutes one case of trisomy 21 was born, and the incidence rate was 1 in 600 to 800 newborns in China.1 In two thirds of cases with trisomy 21, there was a spontaneous abortion, so the actual incidence was higher than that obtained postnatally. Trisomy 21 usually occurred due to meiotic non-disjuncti…     

结核分枝杆菌的荧光定量PCR快速诊断

目的传统的结核分枝杆菌鉴定方法敏感性差、鉴定时间长,影响诊断和治疗,本研究为克服传统方法的缺点,建立特异、敏感、快速的结核分枝杆菌检测方法。方法应用荧光定量PCR技术检测疑似结核病病人痰液中的特异性DNA片段,以达到对结核病病人的快速诊断。结果 PCR结果显示7例疑似结核病病人的痰液标本中检出目的基因片段,证明7例病人均为结核病病人。结论所建立方法可用于结核分枝杆菌的快速诊断。     

脑膜炎奈瑟菌的PCR快速诊断

目的建立特异、敏感、快速的脑膜炎奈瑟菌检测方法。方法应用PCR技术检测流行性脑脊髓膜炎(简称流脑)疑似病例脑脊液和血液标本中脑膜炎奈瑟菌种属(Neisseria meningitides,Nm)及各群的特异性DNA片段。结果 6例流脑疑似病人的脑脊液标本中检出5份Nm CRGA基因阳性,5份含有Nm C群SIAD(C)基因片段;血液标本中检出1份Nm CRGA基因阳性,1份含有Nm C群SIAD(C)基因片段。结论所建立方法可用于Nm的快速诊断。     

应用连锁分析对杜氏/贝氏肌营养不良症家系进行快速携带者检测和产前基因诊断

杜氏 贝氏肌营养不良症 (Ｄｕｃｈｅｎｎｅ Ｂｅｃｋｅｒｍｕｓｃｕｌａｒｄｙｓ ｔｒｏｐｈｙ ,ＤＭＤ ＢＭＤ)是Ｘ连锁隐性遗传病。近年来 ,在ＤＭＤ基因 3′ ,5′端及基因内发现了多个 (ＣＡ)ｎ短串联重复序列 (ｓｈｏｒｔｔａｎｄｅｍｒｅｐｅａｔ,ＳＴＲ)具有多态性 ,且信息量高。用ＳＴＲ进行连锁分析 ,适用于缺失型及非缺失型ＤＭＤ ＢＭＤ患者的基因诊断 ,大大提高了ＤＭＤ ＢＭＤ的可诊断率和产前诊断的准确率 ,成为ＤＭＤ ＢＭＤ快速基因诊断、产前诊断及携带者检测的最重要的方法 ,本室应用该法对 2个ＤＭＤ家系进行了快速的产前基因诊断和携带者检测。1　对象与方法1.1　对象　 2个家系的