Estimation of the Copy Number of Exogenous Genes in Genetically Modified Rice by Droplet Digital PCR

doi:10.13560/j.cnki.biotech.bull.1985.2017-0756

Abstract

Abstract: Copy number of inserted exogenous gene is an important index of assessing the safety of genetically modified organisms. However，there are issues such as poor maneuverability in previous methods for identifying the copy number of gene，therefore，a simple-operation and accurate identification method is urgently needed. This study testes the feasibility of this method while droplet digital PCR was applied to identify the copy number of target gene in transgenic rice. The experimental results showed that the Cry1Ab/PLD ratio of four samples was 674/662，516/541，737/759 and 516/541，respectively，with 0.97 in average. In other words，the copy number of target gene was 1 by droplet digital PCR，which was consistent with the results from Southern blotting. Conclusively，as a novel method to identify the copy number of inserted exogenous gene，droplet digital PCR has some advantages such as simple operation，high accuracy，and flexible design.

Key words: transgenic rice, copy number of target gene, droplet digital PCR（ddPCR）

WANG Yong, LAN Qing-kuo, ZHAO Xin, CHEN Rui, SHEN Xiao-ling, LI Wen, ZHANG Yao-zhong, LI Liang, WANG Qin-ying. Estimation of the Copy Number of Exogenous Genes in Genetically Modified Rice by Droplet Digital PCR[J]. Biotechnology Bulletin, 2018, 34(3): 53-58.

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