孕妇血浆游离胎儿DNA检测在唐氏综合征筛查中的应用价值

Value of detecting free fDNA in maternal plasma in Down′s syndrome screening

目的通过检测唐氏综合征(DS)孕妇血浆中的游离胎儿DNA(fDNA)含量,寻找一种产前筛查DS的新方法。方法选择DS男胎孕妇5例、DS高危男胎孕妇21例、正常男胎孕妇22例,用QIAamp DNA Blood Kit提取孕妇血浆中fDNA,并用TagMan探针实时定量RT-PCR技术进行检测,以Y染色体上的DYS14基因作为男性fDNA的标记物。结果DS孕妇血浆中fDNA为(127.4±58.4)GE/ml,DS高危孕妇为(78.4±28.0)GE/ml,正常孕妇为(48.5±20.8)GE/ml,两两比较,P均<0.01。结论孕妇血浆中游离fDNA定量检测可以作为产前筛查DS的候选指标。

Objective To provide a new marker for prenatal screening Down＇s syndrome （DS） through detecting the maternal free fetal DNA （/DNA）. Methods 5 pregnant women eanying a trisomy DS fetus, 21 DS high-risk pregnant women, and 22 normal pregnant women carrying a male fetus were chosen, fDNA in maternal plasma were extracted with QIAamp DNA Blood Kit. TagMan probe real-time quantitative PCR was used to detect quantitatively DYSI4 gene of fDNA. Results The fDNA was （ 127.4 ±58.4 ） GE/ml for pregnant women carrying a trisomy 21 fetus, （78.4± 28.0 ） GE/ml for DS hlgh-risk pregnant women, and （48.5 ± 20.8 ） GE/ml for normal pregnant women. The remarkable difference between each two groups was statistically significance （P 〈 0. 01 ）. Conclusion tDNA in maternal plasma might be a new marker for prenatal screening DS.