Claudia Paoletti

A statistical assessment of differences and equivalences between genetically modified and reference plant varieties

BackgroundSafety assessment of genetically modified organisms is currently often performed by comparative evaluation. However, natural variation of plant characteristics between commercial varieties is usually not considered explicitly in the statistical computations underlying the assessment.ResultsStatistical methods are described for the assessment of the difference between a genetically modified (GM) plant variety and a conventional non-GM counterpart, and for the assessment of the equivalence between the GM variety and a group of reference plant varieties which have a history of safe use. It is proposed to present the results of both difference and equivalence testing for all relevant plant characteristics simultaneously in one or a few graphs, as an aid for further interpretation in safety assessment. A procedure is suggested to derive equivalence limits from the observed results for the reference plant varieties using a specific implementation of the linear mixed model. Three different equivalence tests are defined to classify any result in one of four equivalence classes. The performance of the proposed methods is investigated by a simulation study, and the methods are illustrated on compositional data from a field study on maize grain.ConclusionsA clear distinction of practical relevance is shown between difference and equivalence testing. The proposed tests are shown to have appropriate performance characteristics by simulation, and the proposed simultaneous graphical representation of results was found to be helpful for the interpretation of results from a practical field trial data set.

Unintended Effects in Genetically Modified Food/Feed Safety: A Way Forward

Identifying and assessing unintended effects in genetically modified food and feed are considered paramount by the Food and Agricultural Organization (FAO), World Health Organization (WHO), and Codex Alimentarius, despite heated debate. This paper addresses outstanding needs: building consensus on the history-of-safe-use concept, harmonizing criteria to select appropriate conventional counterparts, and improving endpoint selection to identify unintended effects.

Variability of crops’ compositional characteristics: What do experimental data show?

Common pillar across the risk assessment strategies implemented worldwide for genetically modified plants is the comparison of their compositional profile to that of conventional counterparts deemed safe. If differences are observed, those that cannot be attributed to natural variation are further evaluated for their safety relevance. This principle is clear, but its implementation is challenging. Here we first discuss the difficulties of estimating natural variation of crop-specific compositional end-points and the various attempts made, together with their advantages and limitations. Second we present the empirical distribution curves of compositional end-points for two crops bearing a large commercial interest worldwide, maize and soybean. These curves provide novel information on end-point specific variability relevant for further progressing in the risk assessment process.

Guidance for the risk assessment of the presence at low level of genetically modified plant material in imported food and feed under Regulation (EC) No 1829/2003

Abstract This document provides guidance for the risk assessment under Regulation (EC) No 1829/2003 of the unintended, adventitious or technically unavoidable presence in food and feed of low level of genetically modified plant material intended for markets other than in the European Union. In this context, the presence at low level is defined to be maximum 0.9% of genetically modified plant material per ingredient. This guidance is intended to assist applicants by indicating which scientific requirements of Annex II of Regulation (EU) No 503/2013 are considered necessary for the risk assessment of the presence at low levels of genetically modified plant material in food and feed.