Validity Assessment of the Detection Method of Maize Event Bt10 through Investigation of Its Molecular Structure

Abstract

In March 2005, U.S. authorities informed the European Commission of the inadvertent release of unauthorized maize GM event Bt10 in their market and subsequently the grain channel. In the United States measures were taken to eliminate Bt10 from seed and grain supplies; in the European Union an embargo for maize gluten and brewer's grain import was implemented unless certified of Bt10 absence with a Bt10-specific PCR detection method. With the aim of assessing the validity of the Bt10 detection method, an in-depth analysis of the molecular organization of the genetic modification of this event was carried out by both the company Syngenta, who produced the event, and the European Commission Joint Research Centre, who validated the detection method. Using a variety of molecular analytical tools, both organizations found the genetic modification of event Bt10 to be very complex in structure, with rearrangements, inversions, and multiple copies of the structural elements (cry1Ab, pat, and the amp gene), interspersed with small genomic maize fragments. Southern blot analyses demonstrated that all Bt10 elements were found tightly linked on one large fragment, including the region that would generate the event-specific PCR amplicon of the Bt10 detection method. This study proposes a hypothetical map of the insert of event Bt10 and concludes that the validated detection method for event Bt10 is fit for its purpose.

Genetically modified seeds and plant propagating material in Europe: potential routes of entrance and current status

“…The number of publications related to contamination by GM seeds and plant propagating material identified by the literature search was relatively small reflecting general lack of information on these issues. Most of the publications were related to GM grains imported for food and feed purposes, which may escape in the environment (Aono et al., 2011; Cowan, 2014; Devos et al., 2012; Gamarra et al., 2011; Goto et al., 2017; Han et al., 2015; Hanzer et al., 2012; Hecht et al., 2014; Yamaguchi et al., 2003; Kawata et al., 2009; Kim et al., 2006; Lamb and Booker, 2011; Macias-De Ia Cerda et al., 2012; Milcamps et al., 2009; Nikolic et al., 2010; Nishizawa et al., 2009; Nishizawa et al., 2016; Nishizawa et al., 2010; Park et al., 2010; Santa-Maria et al., 2014; Schoenenberger and D'Andrea, 2012; Schulze et al., 2015; Schulze et al., 2014; Serratos-Hernandez et al., 2007; Turkec et al., 2016a,b; Zdjelar et al., 2014). Majority of the cases of occurrence of GM seeds have been detected outside European Union, e.g., in Japan, Korea, Mexico or Argentina, and those have been linked to sites of seed import and transport routes.…”

Development of chromogenic detection for biomolecular analysis

“…However, the relatively low sensitivity, narrow dynamic range, and non‐quantitative analysis limit the further application seriously. [ 15–18 ] Therefore, the researchers put lots of effort into exploiting highly sensitive, accurately quantitative chromogenic detection methods for biomolecular analysis. [ 19–22 ]…”

Successful detection of foreign inserts in transgenic rice TT51‐1 (BT63) by RNA‐sequencing combined with PCR

“…The combination of high‐throughput sequencing with computational subtraction has been used to characterise unknown genetic modifications . However, the precise fragment of the inserted genetic elements cannot be measured . Recently, next‐generation sequencing has been used as a powerful tool to identify and characterise genetically modified crops .…”