应用荧光定量PCR产前诊断21三体综合征

Prenatal diagnosis of 21 trisomy syndrome by fluorescence quantitative polymerase chain reaction

目的 建立荧光定量PCR技术产前检测 2 1三体综合征。方法 采用PCR方法同时扩增位于 2 1号染色体上的人肝型磷酸果糖激酶基因 (humanliver typephosphofructokinasegene ,PFKL CH2 1 )和位于 1号染色体上的人肌型磷酸果糖激酶基因(humanmuscle typephosphofructkinasegene ,PFKM CH1 ) ,使用SYBRGreenⅠ荧光染料处理产物、琼脂糖电泳后在凝胶成像系统进行分析 ,得出扩增产物的荧光强度对比值。用此方法检测 2 0例 2 1三体综合征患儿和 2 1例正常人外周血及 1 1例孕妇绒毛或脐带血。结果 2 6例 2 1三体综合征患儿PFKL CH2 1 /PFKM CH1 扩增产物的荧光强度对比值为 1 5 98± 0 1 78,而正常人PFKL CH2 1 /PFKM CH1 扩增产物的荧光强度对比值为 1 0 0 0± 0 0 5 0 ,两者间差别有显著意义。 1 0例孕妇绒毛或脐带血细胞DNA的PFKL -CH2 1 /PFKM -CH1 扩增产物的荧光强度对比值均在 1 0 0± 0 1 0之间 (正常人 x± 2SD) ,1例为 1 5 8,与染色体核型分析结果相符合。结论 SYBRGreenⅠ荧光定量PCR技术产前检测 2 1三体综合征具有准确、快速、安全、实用等特点 ,有较高的临床使用价值。

Objective To establish a prenatal diagnosis method of fluorescence quantitative PCR to detect 21 trisomy syndrome Method At first,using one pair of primer to simultaneously amplify different fragments of two highly homologous genes of the human liver type phosphofructokinase located on chromosome 21 (PFKL CH 21 ) and the human muscular type phosphofructokinase located on chromosome 1(PFKM CH 1) Then,staining the PCR products of these homologous genes with SYBR Green I,comparing the fluorescence intensity of the bands after electrophoresis,analyzing the data We have used this approach to detect 20 cases of 21 trisomy syndrome,21 normal individuals and 11cases of risk fetus.Results The fluorescence intensity relative ratios of PFKL CH 21 / PFKM CH 1 in 21 trisomy syndrome and normol individual were 1 589±0 178 and 1 00±0 050,respectively.The difference between the two groups was highly significant.The ratio value of the 10 risk fetus were 1 01±0 1,among them,one is 1 58 Our results were consistent with expectations made by the means of karotype analysis.Conclusions SYBR Green I fluorescence quantitative polymerase chain reaction is a practical,safe,precise and rapid prenatal diagnosis approach to detect 21 trisomy syndrome.