title: Validation of a sensitive DNA walking strategy to characterise unauthorised GMOs using model food matrices mimicking common rice products.
abstract: To identify unauthorised GMOs in food and feed matrices, an integrated approach has recently been developed targeting pCAMBIA family vectors, highly present in transgenic plants. Their presence is first assessed by qPCR screening and is subsequently confirmed by characterising the transgene flanking regions, using DNA walking. Here, the DNA walking performance has been thoroughly tested for the first time, regarding the targeted DNA quality and quantity. Several assays, on model food matrices mimicking common rice products, have allowed to determine the limit of detection as well as the potential effects of food mixture and processing. This detection system allows the identification of transgenic insertions as low as 10 HGEs and was not affected by the presence of untargeted DNA. Moreover, despite the clear impact of food processing on DNA quality, this method was able to cope with degraded DNA. Given its specificity, sensitivity, reliability, applicability and practicability, the proposed approach is a key detection tool, easily implementable in enforcement laboratories.
authors.affiliation: Scientific Institute of Public Health (WIV-ISP), Platform of Biotechnology and Molecular Biology (PBB) and Biosafety and Biotechnology Unit (SBB), J. Wytsmanstraat 14, 1050 Brussels, Belgium; Institute for Agricultural and Fisheries Research (ILVO), Technology and Food Sciences Unit, Burg. Van Gansberghelaan 115 Bus 1, 9820 Merelbeke, Belgium; University of Gent (UGent), Faculty of Pharmaceutical Sciences, Laboratory of Pharmaceutical Biotechnology, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Marie-Alice
authors.initials: MA
authors.lastname: Fraiture
authors.affiliation: Scientific Institute of Public Health (WIV-ISP), Platform of Biotechnology and Molecular Biology (PBB) and Biosafety and Biotechnology Unit (SBB), J. Wytsmanstraat 14, 1050 Brussels, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Herman
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Technology and Food Sciences Unit, Burg. Van Gansberghelaan 115 Bus 1, 9820 Merelbeke, Belgium.
authors.forename: Isabel
authors.initials: I
authors.lastname: Taverniers
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Technology and Food Sciences Unit, Burg. Van Gansberghelaan 115 Bus 1, 9820 Merelbeke, Belgium; University of Gent (UGent), Faculty of Sciences, Department of Plant Biotechnology and Bioinformatics, Technologiepark 927, 9052 Ghent, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: De Loose
authors.affiliation: University of Gent (UGent), Faculty of Pharmaceutical Sciences, Laboratory of Pharmaceutical Biotechnology, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Filip
authors.initials: F
authors.lastname: Van Nieuwerburgh
authors.affiliation: University of Gent (UGent), Faculty of Pharmaceutical Sciences, Laboratory of Pharmaceutical Biotechnology, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Dieter
authors.initials: D
authors.lastname: Deforce
authors.affiliation: Scientific Institute of Public Health (WIV-ISP), Platform of Biotechnology and Molecular Biology (PBB) and Biosafety and Biotechnology Unit (SBB), J. Wytsmanstraat 14, 1050 Brussels, Belgium. Electronic address: nancy.roosens@wiv-isp.be.
authors.forename: Nancy H
authors.initials: NH
authors.lastname: Roosens
mesh_terms: D003001:Cloning, Molecular; D018744:DNA, Plant / Q000235:genetics / Q000302:isolation & purification*; D005511:Food Handling / Q000379:methods; D030841:Food, Genetically Modified; D012275:Oryza / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
chemical_list: D018744:DNA, Plant
keywords: DNA walking; Detection; Rice food; Sensitivity; Transgene flanking region; Unauthorised GMO