Event-specific detection of genetically modified wheat B73-6-1 based on the 3′-flanking sequence

Abstract

In this study, 3′-flanking sequence between the host plant DNA and the integrated gene construct of pHMW1Dx5 vector in transgenic wheat B73-6-1 was revealed by means of adaptor PCR; thus, the fragment with the length of 3.1 kb was obtained, including a 190-bp wheat genomic DNA, which demonstrates that this HMW-GS gene was located on the wheat chromosome 3B. And the event-specific PCR primers were designed based upon the revealed 3′-flanking sequence; the conventional qualitative PCR and quantitative SYBR real-time PCR detection methods employing these primers were successfully developed. In conventional qualitative PCR assay, the limit of detection was 0.1 % for B73-6-1 wheat genomic DNA for one reaction. In the quantitative SYBR real-time PCR assay, the limit of detection and limit of quantification were 10 and 100 haploid genome copies, respectively. In addition, three mixed blind wheat samples with known B73-6-1 contents were detected using the established real-time PCR systems, and the ideal results indicated that the established event-specific real-time PCR detection systems were reliable, sensitive and accurate.