A novel isothermal detection method for the universal element of genetically modified soybean

Abstract

Due to the increasingly heated debate on the potential threat of genetically modified (GM) crops to human health and environment, regulations and laws relevant to GM crops have been issued in many countries and regions to strictly restrict their cultivation and application. Therefore, fast and accurate method to realized on-site detection of GM crops is greatly demanded. In this work, a novel isothermal amplification method termed denaturation bubble-mediated strand exchange amplification (SEA) was proposed first time to detect GM crops. Fluorescence assay based on SEA could accurately distinguished GM and non-GM soybean by detecting agrobacterium tumefaciens nopaline synthase (NOS) terminator, which was widely incorporated in GM crops. Moreover, this feasible and specific method could detect NOS terminator from as low as 200 pg/μL total genomic DNA of GM soybean. In addition, in the actual sample detection, the result of colorimetric assay based on SEA results could be directly observed by the naked eyes within 58 min. Compared with the traditional methods based on PCR, which normally required complex equipment, skilled technicians and long operation time, this simple, fast and precise method is more desirable for the on-site GM crops detection.