SNP等位位点比例法产前诊断唐氏综合征方法的建立

Prenatal detection of Down′s syndrome by SNP allelic ratio Analysis.

目的建立一种简便直观的产前诊断唐氏综合征的方法。方法提取63例羊水细胞中胎儿DNA,利用分子开关技术对PLAC4基因的rs8130833位点进行特异性扩增,最后采用荧光分光光度计对扩增产物进行光谱分析,根据产物的荧光强度鉴定SNP等位位点比例,从而区分出正常胎儿和唐氏患儿。结果63例羊水细胞中有33例杂合样本,对33例杂合样本进行检测,诊断特异性达94.1%。结论通过荧光光谱进行的SNP等位位点比例分析法简便直观,可以进一步应用在唐氏综合征的非创伤性产前诊断。

Objective： To establish a simple and intuitive method for prenatal diagnosis of Down＇s syndrome. Methods： Fetal D NA were obtained from 63 cases of amniotic fluid cells, the SNP rs8130833 in PLACA was detected by on/off switch method, which could eliminate non - specific amplification, amplified products were analysed with fluorospectrophotometer, to known SNP allelie ratios from fluorescence intensity. Normal fetuses and trisomy 21 fetuses could be distinguished easily. Results： Among 63 cases, 33eases were beterozygous which were detected with fluorescence spectra analysis. The specificity of this method was 94. 1%, Conclusion： Using fluorescence speetra to determine the SNP allelie ratios was simple and direet which could be applied to the noninvasive prenatal dignosis of trisomy 21 in future.