To guarantee the traceability on the market and the freedom of choice for
; consumers, genetically modified organisms (GMO) legislations have been
; established in many countries, including in Europe (EU). However, the
; implementation of these legislations by the enforcement laboratories is becoming
; complex due mainly to the increasing number and diversity of GMO. To cope
; with the problematic of EU unauthorized GMO, this PhD aims to improve and
; strengthen the existing GMO detection system using high-tech approaches.
; First, as a study case, an overview of genetically modified (GM) rice, developed
; around the world was carried out to collect information related inter alia
; on elements found in their transgenic cassette. Second, according to this
; information, key targets, frequently found in GMO (p35S and tNOS) or
; exclusively observed in EU unauthorized GMO (t35S pCAMBIA), were selected
; to develop a strategy allowing to detect and characterize a broad range of
; GMO. This strategy, fully integrated in the GMO routine analysis, consists
; to characterize sequences surrounding detected key transgenic elements using
; a DNA walking approach. By this way, the acquisition of sequences from
; the junction between the transgenic cassette and the plant genome as well as
; the associations of elements typically found in transgenic constructs allow to
; confirm the presence of GMO in food/feed matrices. Due to its good performance
; thoroughly assessed via several unprocessed and processed food/feed matrices,
; this strategy represents a key tool, easily implementable by the enforcement
; laboratories. With the aim to even more simplify the workflow and increase the
; throughput of this strategy, the sequencing step was performed using the Next
; Generation Sequencing (NGS) technology instead of the Sanger technology.
; In parallel, the detection of GMO in alimentary matrices using exclusively the
; NGS technology, through a whole genome sequencing (WGS) approach, was
; also investigated. As this last approach does not theoretically require any prior
; information about the targeted sequences, GMO composed only of unknown
; transgenic elements could be detected.

This work has thus allowed to provide additional strategies to the current GMO
; detection system in order to characterize a larger spectrum of GMO, both
; authorized or not.