Development of event‐specific PCR detection methods for genetically modified tomato Huafan No. 1

Abstract

The genetically modified (GM) tomato Huafan No. 1 is a commercial GM event created in China, and the development of specific methods for its identification and quantification is necessary under labeling regulations for genetically modified organisms (GMOs). The event-specific polymerase chain reaction (PCR) method is the most used method for identification of GMOs in routine analysis. The 3' junction sequence of transgene integration in GM Huafan No. 1 tomato was revealed by thermal asymmetric interlaced PCR (TAIL-PCR) and sequencing analysis. Based on the revealed 3' integration junction sequence, both conventional and real-time PCR assays were developed and validated for GM Huafan No. 1 tomato identification. In the conventional PCR assay, the limit of detection (LOD) was 20 haploid genome copies. In the real-time PCR assay, the LOD and limit of quantification (LOQ) were estimated to be 5 and 10 tomato haploid genome copies, respectively. Furthermore, the developed PCR methods were well validated by in-house validation. Our results suggest that the developed event-specific PCR methods can be routinely used for identification and quantification of GM Huafan No. 1 tomato.