Allergy Risk Assessment for Newly Expressed Proteins (NEPs) in Genetically Modified (GM) Plants


  • Scott McClain Syngenta, Crop Protection, LLC., Research Triangle Park, NC
  • Rod A. Herman Corteva Agriscience™, Johnston, IA
  • Emir Islamovic BASF Corporation, Research Triangle Park, NC
  • Rakesh Ranjan BASF Corporation, Research Triangle Park, NC
  • Andre Silvanovich Bayer, Crop Science Division, Chesterfield, MO
  • Ping Song Corteva Agriscience™, Johnston, IA
  • Laurie Goodwin CropLife International, Washington, DC



genetically modified, allergenicity assessment, food and feed, hazard, exposure, risk, core studies, supplementary studies


Based on experience and scientific advancements over the past two decades, a revised approach for the assessment of the allergenic potential of newly expressed proteins (NEPs) in genetically modified (GM) plants is warranted. NEPs are most often not native to the crop genome, and thus regulatory reviews of the safety of GM plants include an assessment of the allergenic potential of NEPs. International standards for the assessment of allergenicity first developed in the mid-1990s required a series of characterization studies to be conducted that are, to some extent, still applicable today to the risk assessment of GM plants, with most modern versions represented in the Codex Alimentarius. This standardized guidance on allergenicity assessments, including the required characterization studies, presented two primary challenges. First, there was (and still is) no defined and accepted model (animal or in vitro) for directly testing allergy potential. Second, bioinformatic analyses were prescribed using thresholds for hazard identification that were neither universal for all allergens nor tested prior to the implementation of requirements into guidance documents. Herein, risk assessment principles are applied to structure the assessment of the allergenic potential of NEPs. This allergy risk assessment is built on a foundation of: 1) identifying hazard by assessing similarity to known allergens, and 2) assessing exposure when a hazard is identified. Supplementary studies such as IgE binding may need to be performed in special cases. These recommended revisions to current approaches to the assessment of allergy potential are designed to ensure a realistic, case-by-case approach, and consider updated molecular biology, genomics, and bioinformatic techniques that were unavailable when earlier allergy risk assessment approaches were established.

doi: 10.21423/jrs-v09i1mcclain


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