陈 玲¹ 刘 超² 王慧君¹ 邱平明¹

（1.南方医科大学法医学系，广州 510515； 2.广州市刑事科学技术研究所，广州 510030）

【摘 要】 目的 探讨多重置换扩增（MDA）技术对法医学微量 DNA 样品 STR 检测分型的效果。方法用MDA技术对不同模板量DNA进行全基因组扩增(WGA)，扩增产物用实时荧光定量 PCR 技术定量、用ProfilerPlusTM 试剂盒检测基因型。结果该方法可对模板 DNA 增加104～106 倍。1 ng 样品DNA的MDA产物可获得9个STR基因座和Amelogenin性别基因座的准确分型结果；低于0.1 ng的样品DNA经MDA扩增后，基因座检出数增加，但可见等位基因不平衡或丢失现象。结论 MDA 技术可有效增加DNA模板量和提高微量DNA分型效果。但样品 DNA 量低于0.1 ng 时，MDA产物的 STR 分型结果判读须慎重。

【关键词】 多重置换扩增；全基因组扩增；微量 DNA 检测

【中图分类号】 D919.2

【文献标识码】 A

【文章编号】 1674-1226(2008)06-0752-05

Effect of multiple displacement amplification on forensic minute DNA analysis. Chen Ling. Institute of Forensic Medicine, Southern Medical University, Guangzhou 501515

【Abstract】 Objective To study the effect of multiple displacement amplification (MDA) on forensic minute DNA analysis. Methods Whole genome amplification (WGA) was performed for various amount of sample DNA,and the amplified products were quantitated by real-time quantitative PCR and genotyped by Profiler PlusTM kit.Results The template DNA can be amplified 104 to 106 folds by MDA. Using this technology, all 9 STR loci and Amelogenin gene can be correctly genotyped by MDA from 1ng genomic DNA. When the genomic DNA is not more than 0.1 ng, The loci detected of MDA products are more than the sample DNA not for MDA, but allelic dropouts and allelic imbalance of MDA products was observed. Conclusion MDA is helpful for increasing the ammount of minite DNA and improving the effect of minite DNA analysis. If the sample DNA is not more than 0.1ng, the caution should be put into the STR genotypes of their MDA products.

【Key Words】 Multiple displacement amplification, Whole genome amplification, Minute DNA analysis