Abstract: In this study, a duplex PCR detection method for three genetically modified soybean of MON87705, MON87769 and DP356043 was established by droplet digital PCR (ddPCR) platform. Taking  advantage of specificity and quantitative range of duplex digital PCR, the primer probe combination and experimental procedure was optimized, exogenous genes and reference gene were detected. The experiment result showed that the primer probe combination used in the experiment only produced fluorescent signal for the target soybean line in the digital PCR method. It can be used in the detection of genetically modified soybean for its specificity. The genetically modified ingredients content was basically the same as reference parameters. The quantitative detection limit was 0.5%, and the qualitative detection limit was 0.05%, which could meet the needs of the detection of low-purity sample. The study also determined the gene copy number of transgenic soybean, which indicated that the dual digital PCR system established in this study can accurately and stably meet the actual detection needs, and has a good development prospect in practical application.

Key words: duplex droplet digital PCR, genetically modified soybean, quantitative detection

摘要： 利用微滴式数字PCR(droplet digital PCR, ddPCR)平台建立针对MON87705、MON87769、DP356043三种转基因大豆中外源基因的双重PCR检测方法。利用双重数字PCR方法检测特异性、定量范围等参数，优化所用引物探针组合及实验体系程序，检测外源基因与内标准基因的拷贝数。结果表明，所用引物探针组合在数字PCR方法中仅对目标大豆品系有荧光信号，具有特异性，可用于转基因大豆品系的筛选与鉴别。检测了大豆的转基因成分含量，结果与材料标准品参数基本一致，并根据结果设定定量检测限为0.5%，定性检测限为0.05%，可满足低纯度样品检测的需求。双重数字PCR体系能够准确且稳定的满足实际检测需要，在实际应用上具有良好的发展前景。

关键词: 双重数字PCR, 转基因大豆, 定量检测