Chelex法和两种磁珠法提取接触DNA效果的比较

目的比较Chelex法、DNA IQ磁珠法、EQ国产磁珠法对接触DNA的提取效果。方法将稀释为10ng、100ng的标准品DNA,分别采用Chelex法、DNA IQ磁珠法、EQ国产磁珠法处理;对30例烟蒂和30例牙刷分别采用Chelex法、DNA IQ磁珠法和EQ国产磁珠法提取DNA,然后进行PCR定量和STR检测。结果Chelex法对DNA的提取无损失,DNA IQ磁珠法、EQ国产磁珠法对DNA的提取均有不同程度的损失;烟蒂、牙刷等检材采用Chelex法提取的接触DNA量和IPC CT值显著高于IQ磁珠法、EQ国产磁珠法,但STR检验成功率却低于IQ磁珠法、EQ国产磁珠法。2种磁珠法提取的DNA量、IPC CT值和STR检验成功率无显著性差异。结论污染轻、杂质少的接触DNA检材,用Chelex法提取最为方便快捷;IQ磁珠法、EQ国产磁珠法更适合污染接触DNA检材的提取及自动化操作。

The comparison of the extraction effects of touch DNA by the Chelex-100 and magnetic beads

Objective To compare the extraction effects of touch DNA by Chelex-100,DNA IQ and EQ magnetic beads.Methods The standard DNA diluted to 10ng,100ng was treated respectively by Chelex-100,DNA IQ system and EQ magnetic beads.DNA was extracted from 30 cigarette butts and 30 toothbrushes respectively by the three methods.The quality and quantity of DNA were detected between PCR quantification and STR analysis.Results There wasn’t any loss of DNA with the Chelex method,but with DNA IQ method and the EQ magnetic beads method,some DNA was lost.For cigarette butts and toothbrushes samples,yield of touch DNA and IPC CT extracted by Chelex method are higher than that extracted by DNA IQ method and the EQ magnetic beads method,but they aren’t significantly different by DNA IQ method and EQ magnetic beads method.Conclusion The Chelex method is very suitable for extracting DNA from the less pollution and low impurity samples,and the DNA IQ system and the EQ magnetic beads method are more suitable for minute and polluted samples.