Event specific real-time quantitative PCR for genetically modified Bt11 maize (Zea mays)

• Published in: European food research & technology Vol. 216; no. 4; pp. 347 - 354
• Main Authors: RØNNING, Sissel B, VAÏTILINGOM, Marc, BERDAL, Knut G, HOLST-JENSEN, Arne
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-04-2003; Berlin Springer Nature B.V
• Subjects: Biological and medical sciences; Cereal and baking product industries; Corn; Deoxyribonucleic acid; DNA; Food; Food industries; Fundamental and applied biological sciences. Psychology; Genes; Genetically altered foods; Genetically modified organisms; Polymerase chain reaction; Processed foods; Raw materials; Studies; Zea mays; Monocotyledones; Molecular integration; Event-specific PCR; Cereal crop; Site specificity; Detection and quantitation limit; Real-time PCR; Gramineae; Detection limit; Angiospermae; Bt11 maize; Transgenic plant; Molecular probe; Quantitative analysis; Zea mays; Integration site; Corn; GMO; Real time; Polymerase chain reaction; Cereal; Spermatophyta; Molecular biology; Detection; Genetically modified organism
• ISSN: 1438-2377; 1438-2385
• DOI: 10.1007/s00217-002-0653-4

We report the characterisation of the 3'-integration junction between host plant DNA and integrated gene-construct of the genetically modified Bt11 maize, and the successive development and first validation of a transformation event-specific quantitative TaqMan 5'-nuclease PCR assay for detection and quantitation of Bt11 maize on the LightCycler. The transgenic DNA in Bt11 is inserted in a tandem repeated DNA sequence motif of approximately 180 bp, and we discuss some of the problems this creates for design, development and validation of event-specific PCR assays. The limit of detection of the PCR assay was estimated to 10 initial template copies. The limit of quantitation in pure maize materials was estimated to approximately 40 template copies. In food samples containing high levels of exogenous DNA, the impact of this DNA was estimated to increase the limit of quantitation to approximately 100 initial template copies. Because of the low number of template copies required for detection and quantification, in combination with small size of the amplicon (~100 bp), the assay may be applied to analyses of raw materials as well as processed food and feed.[PUBLICATION ABSTRACT]