A construct-specific qualitative and quantitative PCR detection method of transgenic maize BVLA430101

Transgenic phytase maize (Zea mays L.) line BVLA430101 was the first transgenic maize obtained the security certification in 2009 in China. However, the construct of the phytase gene expression cassette and the specific detection method have not been reported yet. In this study, the phytase gene expression cassette was identified, which include maize legumin promoter, signal peptide, phytase gene, and maize legumin terminator. The construct-specific qualitative and quantitative PCR methods of BVLA430101 maize were established based on the transition of signal peptide and phytase gene using a maize taxon-specific gene zSSIIb as the endogenous gene. The detection limit for the conventional qualitative PCR was 200 haploid genome copies of BVLA430101. The absolute limit of quantification of the real-time PCR was about 20 haploid genome copies. In addition, two known BVLA430101 contents (5 and 1%) of mixed genomic DNA (V/V) were quantified using the developed real-time PCR detection system, which indicated that the developed quantitative method can be employed reliably for transgenic phytase maize BVLA430101 measurement.