荧光定量PCR技术应用于早孕期胚胎染色体检查的研究

The study of choromosome analysis in early pregnancy using QF-PCR

目的:探讨应用荧光定量PCR(QF-PCR)法检查早孕期胚胎胚外体腔液(ECF)胎儿细胞染色体的可行性。方法:32例孕6-10周正常妊娠选择性人工流产与宫内停育妊娠于宫内手术前行阴道超声引导下胚外体腔穿刺术,取ECF并提取DNA,采用QF-PCR技术分析13,18,21号染色体数目,与绒毛长期培养染色体核型分析结果对比。结果:QF-PCR检测ECF成功率为84.7%(27/32);正常妊娠组QF-PCR检测13,18,21号染色体数目结果与绒毛长期培养染色体核型分析结果符合率100%;宫内停育妊娠组QF-PCR检查发现21-三体,13三体,18三体各1例,绒毛长期培养染色体核型分别为47xy+21/46XX(96%/4%),47XY+13,48xy+10+18;另有46XX der(14;21)(p10;q10),47xy+16;45XO各1例。QF-PCR检测目标染色体数目异常符合率为100%,不能检测染色体结构异常。结论:QF-PCR能够检测ECF目标染色体核型,结合胚外体腔穿刺术将目前的产前遗传学诊断时间提前至孕6-10周,是重要的早孕期胚胎染色体检查技术。

Aim：To study the feasibility of aneuploidy diagnosis using coelocentesis combining with quantitative fluoresce polymerase chain reaction （QF-PCR） in early pregnancy. Methods： 32 cases of normal pregnancies and spontaneous miscarriage were performed coelocentesis before planned operation. QF-PCR were applied to the aspirated exocoelomic fluid （ECF） to detect aneuploidy of chromosome 13, 18 and 21, the result were compared with CVS cytogenetic analysis result. Results： QF-PCR was successful applied in 84.7% cases（27/32）. The copy numbers of chromosome 13,18,21 detected by QF-PCR were totally same as CVS cytogenetic analysis result in normal pregnancy group. In group of spontaneous miscarriage, 21 -trisomy, 13-trisomy and 18-trisomy were found 1 case separately by detecting ECF using QF-PCR. the results were： 47xy ＋21/46XX（96/4% ） 1 case, 47xy ＋21/46XX（96%/4% ） 1 case,47XY ＋13 1 case, 48xy ＋10 ＋18 1 caseand46XXder （14;21）（p10;q10）,47xy＋16;45XO 1 case separately by choronic villi cytogenetic analysis in this group. The coincidence rate for copy numbers of 21,13,18 chromosome were 100%, but QF-PCR can＇t be applicable for non-aimed chromosome and chromosome structure analysis. Conelusion：QF-PCR can be applied to ECF for aimed chromosomeanalysis, prenatal genetic diagnosis can be advanced to gestational 6 - 10 weeks by QF-PCR combined with coelocentesis.