Clausen Frederik Banch, Krog Grethe Risum, Rieneck Klaus, Dziegiel Morten Hanefeld
H:S Blodbank KI2034, Copenhagen University Hospital, Copenhagen, Denmark.
Prenat Diagn. 2007 Jan;27(1):6-10. doi: 10.1002/pd.1605.
Prenatal diagnostic assays have been developed using free fetal DNA circulating in the maternal blood of pregnant women. Efficient DNA extraction is crucial for a robust analysis. To improve fetal DNA yield, we tested two manual extraction methods--the NucliSens Magnetic Extraction (NMAG) system and the QIAamp DSP Virus Kit (QDSP)--against our current standard method, the widely used QIAamp DNA Blood Mini Kit (QDNA).
The fetal DNA yield of the two extraction systems was evaluated using the RHD exon 7 as target in DNA extracts of 75 plasma samples from pregnant RhD-negative women, known to have given birth to RhD-positive infanto. The total DNA yield was evaluated in 23 samples, targeting GAPDH.
The fetal DNA yield was improved by a mean factor of 1.7 using the NMAG system, and improved by a mean factor of 1.5 using the QDSP. The total DNA yield was improved by a mean factor of 2.3 using the NMAG system, and by a mean factor of 1.3 using the QDSP.
Both extraction systems tested were superior to our standard with regard to DNA yield. This improvement may have a great impact on the success of genotyping in early pregnancy.
利用孕妇母血中循环的游离胎儿DNA开发了产前诊断检测方法。高效的DNA提取对于可靠的分析至关重要。为提高胎儿DNA产量，我们将两种手工提取方法——NucliSens磁珠提取（NMAG）系统和QIAamp DSP病毒提取试剂盒（QDSP）——与我们目前的标准方法、广泛使用的QIAamp DNA血液微量提取试剂盒（QDNA）进行了比较。
以RHD基因第7外显子为靶点，对75例已知分娩出RhD阳性婴儿的RhD阴性孕妇血浆样本提取物中的胎儿DNA产量进行评估。以甘油醛-3-磷酸脱氢酶（GAPDH）为靶点，对23个样本的总DNA产量进行评估。
使用NMAG系统时，胎儿DNA产量平均提高了1.7倍；使用QDSP时，平均提高了1.5倍。使用NMAG系统时，总DNA产量平均提高了2.3倍；使用QDSP时，平均提高了1.3倍。
就DNA产量而言，所测试的两种提取系统均优于我们的标准方法。这一改进可能对早期妊娠基因分型的成功产生重大影响。
