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Kedar O, Golberg A, Obolski U, Confino-Cohen R. Allergic to bureaucracy? Regulatory allergenicity assessments of novel food: Motivations, challenges, compromises, and possibilities. Compr Rev Food Sci Food Saf 2024; 23:e13300. [PMID: 38477215 DOI: 10.1111/1541-4337.13300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/12/2023] [Accepted: 12/12/2023] [Indexed: 03/14/2024]
Abstract
New sources of proteins are essential to meet the demands of the growing world population and evolving food trends. Assessing the allergenicity of proteins in novel food (NF) poses a significant food safety regulatory challenge. The Codex Alimentarius Commission presented an allergenicity assessment protocol for genetically modified (GM) foods, which can also be adapted for NF. Since no single laboratory test can adequately predict the allergenic potential of NF, the protocol follows a weight-of-evidence approach, evaluated by experts, as part of a risk management process. Regulatory bodies worldwide have adopted this safety protocol, which, among other things, promotes global harmonization. This review unravels the reliability and various motivations, terms, concepts, and approaches of allergenicity assessments, aiming to enhance understanding among manufacturers and the public. Health Canada, Food Safety Commission JAPAN, and Food Standards Australia New Zealand were surveyed, focusing on the European Food Safety Authority and the US Food Safety Administration for examples of scientific opinions regarding allergenicity assessments for novel and GM foods, from 2019 to 2023. According to our findings, current regulatory allergenicity assessments for NF approval primarily rely on literature reviews. Only a few of the NF assessments proactively presented additional tests. We recommend conducting bioinformatic analyses on NF when a panel of experts deems that there is insufficient prior scientific research.
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Affiliation(s)
- Odeya Kedar
- Faculty of Exact Sciences, Department of Environmental Studies, The Porter School of Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Alexander Golberg
- Faculty of Exact Sciences, Department of Environmental Studies, The Porter School of Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Uri Obolski
- Faculty of Exact Sciences, Department of Environmental Studies, The Porter School of Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
- Faculty of Medicine, School of Public Health, Department of Epidemiology and Preventive Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ronit Confino-Cohen
- Allergy and Clinical Immunology Unit, Meir Medical Center, Kfar Saba, Israel
- School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Carlson AB, Mathesius CA, Gunderson TA, Hession A, Bruyere R, Mirsky HP, Zhang J, Sandmann M, Fallers MN, Herman RA. Protein familiarity is a fundamental but rarely operationalized concept in the safety assessment of genetically modified crops: example of phosphomannose isomerase (PMI). Transgenic Res 2023; 32:423-435. [PMID: 37415055 PMCID: PMC10602950 DOI: 10.1007/s11248-023-00358-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 06/01/2023] [Indexed: 07/08/2023]
Abstract
Fundamental to the safety assessment of genetically modified (GM) crops is the concept of negligible risk for newly expressed proteins for which there is a history of safe use. Although this simple concept has been stated in international and regional guidance for assessing the risk of newly expressed proteins in GM crops, its full implementation by regulatory authorities has been lacking. As a result, safety studies are often repeated at a significant expenditure of resources by developers, study results are repeatedly reviewed by regulators, and animals are sacrificed needlessly to complete redundant animal toxicity studies. This situation is illustrated using the example of the selectable marker phosphomannose isomerase (PMI) for which familiarity has been established. Reviewed is the history of safe use for PMI and predictable results of newly conducted safety studies including bioinformatic comparisons, resistance to digestion, and acute toxicity that were repeated to gain regulatory reapproval of PMI expressed from constructs in recently developed GM maize. As expected, the results of these newly repeated hazard-identification and characterization studies for PMI indicate negligible risk. PMI expressed in recently developed GM crops provides an opportunity to use the concept of familiarity by regulatory authorities to reduce risk-disproportionate regulation of these new events and lessen the resulting waste of both developer and regulator resources, as well as eliminate unnecessary animal testing. This would also correctly imply that familiar proteins like PMI have negligible risk. Together, such modernization of regulations would benefit society through enabling broader and faster access to needed technologies.
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Affiliation(s)
- Anne B Carlson
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | | | - Tim A Gunderson
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | - Aideen Hession
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | - Reba Bruyere
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | - Henry P Mirsky
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | - John Zhang
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | - Mat Sandmann
- Corteva Agriscience, 8325 NW 62nd Avenue, Johnston, IA, 50131, USA
| | - Melissa N Fallers
- Corteva Agriscience, Haskell R&D Center, P.O. Box 30, Newark, DE, 19714, USA
| | - Rod A Herman
- Corteva Agriscience, 9330 Zionsville Road, Indianapolis, IN, 46268, USA
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Herman RA, Song P. Comprehensive COMPARE database reduces allergenic risk of novel food proteins. GM CROPS & FOOD 2022; 13:112-118. [PMID: 35674136 PMCID: PMC9196780 DOI: 10.1080/21645698.2022.2079180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The comprehensiveness of the allergen database used to bioinformatically compare a novel food protein with known allergens is critical to the ability to assess the allergenic risk of newly expressed proteins in genetically engineered crops. The strength of the relationship between a candidate GE protein's amino acid sequence and that of known allergens is used to predict cross-reactive risk. The number of truly novel allergen sequences added annually to the COMPARE database reflects on the comprehensiveness of our knowledge of allergen amino acid sequence diversity. Here, we investigated the most recent five years of updates to the COMPARE allergen database for truly novel entries. Results indicate that few truly novel sequences are added each year, suggesting that the database and our knowledge of allergen sequence diversity is currently quite comprehensive, and that current in silico prediction of allergenic risk for novel food proteins is robust.
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Affiliation(s)
- Rod A. Herman
- Regulatory and Stewardship, Corteva Agriscience, Indianapolis, Indiana, USA,CONTACT Rod A. Herman Corteva Agriscience, 9330 Zionsville Road, Indianapolis, Indiana46268
| | - Ping Song
- Regulatory and Stewardship, Corteva Agriscience, Indianapolis, Indiana, USA
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4
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Safety assessment of the insecticidal protein IPD079Ea from the fern, Ophioglossum pendulum. Food Chem Toxicol 2022; 166:113187. [PMID: 35688270 DOI: 10.1016/j.fct.2022.113187] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 05/05/2022] [Accepted: 05/25/2022] [Indexed: 11/22/2022]
Abstract
As agricultural biotechnology continues to develop solutions for addressing crop pests through newly expressed proteins from novel source organisms, with different modes or sites of action and/or different spectra of activity, the safety of these proteins will be assessed. The results of hazard-identification and characterization studies for the insecticidal protein IPD079Ea, which is derived from a fern (Ophioglossum pendulum) and active against the maize pest western corn rootworm (Diabrotica virgifera virgifera, Coleoptera: Chrysomelidae) are provided. Collectively these results indicate that IPD079Ea is unlikely to present a hazard to human or animal health and support the safety of genetically modified maize expressing IPD079Ea.
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Abstract
Bioinformatic amino acid sequence searches are used, in part, to assess the potential allergenic risk of newly expressed proteins in genetically engineered crops. Previous work has demonstrated that the searches required by government regulatory agencies falsely implicate many proteins from rarely allergenic crops as an allergenic risk. However, many proteins are found in crops at concentrations that may be insufficient to cause allergy. Here we used a recently developed set of high-abundance non-allergenic proteins to determine the false-positive rates for several algorithms required by regulatory bodies, and also for an alternative 1:1 FASTA approach previously found to be equally sensitive to the official sliding-window method, but far more selective. The current investigation confirms these earlier findings while addressing dietary exposure.
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Affiliation(s)
- Rod A Herman
- Regulatory and Stewardship, Corteva Agriscience, Indianapolis, IN, USA
| | - Ping Song
- Regulatory and Stewardship, Corteva Agriscience, Indianapolis, IN, USA
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Carlson AB, Mathesius CA, Ballou S, Boeckman CJ, Gunderson TA, Mirsky HP, Mukerji P, Roe JC, Schmidt JM, Zhang J, Delaney B. Safety assessment of coleopteran active IPD072Aa protein from Pseudomonas chlororaphis. Food Chem Toxicol 2019; 129:376-381. [DOI: 10.1016/j.fct.2019.04.055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/28/2019] [Accepted: 04/29/2019] [Indexed: 10/26/2022]
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Ladics GS. Assessment of the potential allergenicity of genetically-engineered food crops. J Immunotoxicol 2018; 16:43-53. [PMID: 30409058 DOI: 10.1080/1547691x.2018.1533904] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
An extensive safety assessment process exists for genetically-engineered (GE) crops. The assessment includes an evaluation of the introduced protein as well as the crop containing the protein with the goal of demonstrating the GE crop is "as-safe-as" non-GE crops in the food supply. One of the evaluations for GE crops is to assess the expressed protein for allergenic potential. Currently, no single factor is recognized as a predictor for protein allergenicity. Therefore, a weight-of-the-evidence approach, which accounts for a variety of factors and approaches for an overall assessment of allergenic potential, is conducted. This assessment includes an evaluation of the history of exposure and safety of the gene(s) source; protein structure (e.g. amino acid sequence identity to human allergens); stability of the protein to pepsin digestion in vitro; heat stability of the protein; glycosylation status; and when appropriate, specific IgE binding studies with sera from relevant clinically allergic subjects. Since GE crops were first commercialized over 20 years ago, there is no proof that the introduced novel protein(s) in any commercialized GE food crop has caused food allergy.
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Herman RA, Ladics GS. Allergenic sensitization versus elicitation risk criteria for novel food proteins. Regul Toxicol Pharmacol 2018; 94:283-285. [PMID: 29481837 DOI: 10.1016/j.yrtph.2018.02.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 02/20/2018] [Accepted: 02/22/2018] [Indexed: 01/16/2023]
Abstract
The value of criteria used in the weight-of-evidence assessment of allergenic risk of genetically modified (GM) crops has been debated. This debate may originate, in part, from not specifying if the criteria are intended to contribute to the assessment of sensitization risk or elicitation risk. Here, this distinction is explicitly discussed in the context of exposure and hazard. GM crops with structural relationships with known allergens or sourced from an organism known to cause allergy (hazard) are screened for IgE-antibody reactivity using serum from sensitized individuals. If IgE reactivity is observed, the GM crop is not developed. While digestive and heat stability impact exposure and thus the elicitation risk to sensitized individuals, these attributes are not interpretable relative to sensitization risk. For novel food proteins with no identified hazard, heat stability cannot be validly assessed because relevant IgE antibodies are not available. Likewise, the uncertain and sometime non-monotonic dose relationship between oral exposure to allergens and sensitization makes digestive stability a poor predictor of sensitization risk. It is hoped that by explicitly distinguishing between sensitization risk and elicitation risk, some of the debate surrounding the weight-of evidence criteria for predicting the allergenic risk of GM crops can be resolved.
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Affiliation(s)
- Rod A Herman
- Dow AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN 46268, United States.
| | - Gregory S Ladics
- DuPont Haskell Global Centers for Health and Environmental Sciences, 1090 Elkton Road, Newark, DE 19711, United States
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Remington B, Broekman HCH, Blom WM, Capt A, Crevel RWR, Dimitrov I, Faeste CK, Fernandez-Canton R, Giavi S, Houben GF, Glenn KC, Madsen CB, Kruizinga AK, Constable A. Approaches to assess IgE mediated allergy risks (sensitization and cross-reactivity) from new or modified dietary proteins. Food Chem Toxicol 2017; 112:97-107. [PMID: 29258956 DOI: 10.1016/j.fct.2017.12.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 11/03/2017] [Accepted: 12/15/2017] [Indexed: 11/16/2022]
Abstract
The development and introduction of new dietary protein sources has the potential to improve food supply sustainability. Understanding the potential allergenicity of these new or modified proteins is crucial to ensure protection of public health. Exposure to new proteins may result in de novo sensitization, with or without clinical allergy, or clinical reactions through cross-reactivity. In this paper we review the potential of current methodologies (in silico, in vitro degradation, in vitro IgE binding, animal models and clinical studies) to address these outcomes for risk assessment purposes for new proteins, and especially to identify and characterise the risk of sensitization for IgE mediated allergy from oral exposure. Existing tools and tests are capable of assessing potential crossreactivity. However, there are few possibilities to assess the hazard due to de novo sensitization. The only methods available are in vivo models, but many limitations exist to use them for assessing risk. We conclude that there is a need to understand which criteria adequately define allergenicity for risk assessment purposes, and from these criteria develop a more suitable battery of tests to distinguish between proteins of high and low allergenicity, which can then be applied to assess new proteins with unknown risks.
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Affiliation(s)
| | - H C H Broekman
- Dep. Dermatology/Allergology, University Medical Centre Utrecht (UMCU), P.O. Box 85500, The Netherlands
| | | | - A Capt
- Bayer SAS, Sophia Antipolis, France
| | - R W R Crevel
- Safety & Environmental Assurance Centre, Unilever, Bedford, UK
| | - I Dimitrov
- Faculty of Pharmacy, Medical University of Sofia, Sofia, 1000 Bulgaria
| | - C K Faeste
- Norwegian Veterinary Institute, Oslo, Norway
| | - R Fernandez-Canton
- Monsanto Europe S.A., Avenue de Tervuren 270-272, B-1150 Brussels, Belgium
| | - S Giavi
- Allergy Department, 2nd Paediatric Clinic, University of Athens, Athens, Greece
| | | | - K C Glenn
- Monsanto Company, 800 N. Lindbergh Boulevard, St. Louis, MO 63017, USA
| | - C B Madsen
- National Food Institute, Technical University of Denmark, Søborg, Denmark
| | | | - A Constable
- Nestec Ltd, P.O. Box 44, CH-1000 Lausanne 26, Switzerland
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10
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Food safety assessment of Cry8Ka5 mutant protein using Cry1Ac as a control Bt protein. Food Chem Toxicol 2015; 81:81-91. [DOI: 10.1016/j.fct.2015.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 02/01/2015] [Accepted: 04/03/2015] [Indexed: 12/22/2022]
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Koch MS, Ward JM, Levine SL, Baum JA, Vicini JL, Hammond BG. The food and environmental safety of Bt crops. FRONTIERS IN PLANT SCIENCE 2015; 6:283. [PMID: 25972882 PMCID: PMC4413729 DOI: 10.3389/fpls.2015.00283] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 04/08/2015] [Indexed: 05/28/2023]
Abstract
Bacillus thuringiensis (Bt) microbial pesticides have a 50-year history of safety in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s). Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals, and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms.
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12
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Koch MS, Ward JM, Levine SL, Baum JA, Vicini JL, Hammond BG. The food and environmental safety of Bt crops. FRONTIERS IN PLANT SCIENCE 2015; 6:283. [PMID: 25972882 DOI: 10.3389/fpls.2015.0028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 04/08/2015] [Indexed: 05/28/2023]
Abstract
Bacillus thuringiensis (Bt) microbial pesticides have a 50-year history of safety in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s). Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals, and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms.
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Herman RA, Raybould A. Expert opinion vs. empirical evidence: the precautionary principle applied to GM crops. GM CROPS & FOOD 2014; 5:8-10. [PMID: 24637724 PMCID: PMC5033208 DOI: 10.4161/gmcr.28331] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Expert opinion is often sought by government regulatory agencies when there is insufficient empirical evidence to judge the safety implications of a course of action. However, it can be reckless to continue following expert opinion when a preponderance of evidence is amassed that conflicts with this opinion. Factual evidence should always trump opinion in prioritizing the information that is used to guide regulatory policy. Evidence-based medicine has seen a dramatic upturn in recent years spurred by examples where evidence indicated that certain treatments recommended by expert opinions increased death rates. We suggest that scientific evidence should also take priority over expert opinion in the regulation of genetically modified crops (GM). Examples of regulatory data requirements that are not justified based on the mass of evidence are described, and it is suggested that expertise in risk assessment should guide evidence-based regulation of GM crops.
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Affiliation(s)
| | - Alan Raybould
- Syngenta; Jealott's Hill International Research Centre; Bracknell, UK
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Prado JR, Segers G, Voelker T, Carson D, Dobert R, Phillips J, Cook K, Cornejo C, Monken J, Grapes L, Reynolds T, Martino-Catt S. Genetically engineered crops: from idea to product. ANNUAL REVIEW OF PLANT BIOLOGY 2014; 65:769-90. [PMID: 24579994 DOI: 10.1146/annurev-arplant-050213-040039] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Genetically engineered crops were first commercialized in 1994 and since then have been rapidly adopted, enabling growers to more effectively manage pests and increase crop productivity while ensuring food, feed, and environmental safety. The development of these crops is complex and based on rigorous science that must be well coordinated to create a plant with desired beneficial phenotypes. This article describes the general process by which a genetically engineered crop is developed from an initial concept to a commercialized product.
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Hammond B, Kough J, Herouet-Guicheney C, Jez JM. Toxicological evaluation of proteins introduced into food crops. Crit Rev Toxicol 2013; 43 Suppl 2:25-42. [PMID: 24164515 PMCID: PMC3835160 DOI: 10.3109/10408444.2013.842956] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 09/04/2013] [Accepted: 09/06/2013] [Indexed: 11/13/2022]
Abstract
This manuscript focuses on the toxicological evaluation of proteins introduced into GM crops to impart desired traits. In many cases, introduced proteins can be shown to have a history of safe use. Where modifications have been made to proteins, experience has shown that it is highly unlikely that modification of amino acid sequences can make a non-toxic protein toxic. Moreover, if the modified protein still retains its biological function, and this function is found in related proteins that have a history of safe use (HOSU) in food, and the exposure level is similar to functionally related proteins, then the modified protein could also be considered to be "as-safe-as" those that have a HOSU. Within nature, there can be considerable evolutionary changes in the amino acid sequence of proteins within the same family, yet these proteins share the same biological function. In general, food crops such as maize, soy, rice, canola etc. are subjected to a variety of processing conditions to generate different food products. Processing conditions such as cooking, modification of pH conditions, and mechanical shearing can often denature proteins in these crops resulting in a loss of functional activity. These same processing conditions can also markedly lower human dietary exposure to (functionally active) proteins. Safety testing of an introduced protein could be indicated if its biological function was not adequately characterized and/or it was shown to be structurally/functionally related to proteins that are known to be toxic to mammals.
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Affiliation(s)
| | - John Kough
- Office of Pesticide Programs, Microbial Pesticides Branch, US Environmental Protection AgencyWashington, DCUSA
| | | | - Joseph M. Jez
- Department of Biology, Washington University in St. LouisSt. Louis, MOUSA
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Herman RA, Ekmay R. Do whole-food animal feeding studies have any value in the safety assessment of GM crops? Regul Toxicol Pharmacol 2013; 68:171-4. [PMID: 23851038 DOI: 10.1016/j.yrtph.2013.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 06/19/2013] [Accepted: 07/03/2013] [Indexed: 12/01/2022]
Abstract
The use of whole-food (grain meal contained in feed) animal-feeding studies to support the safety assessment of genetically modified crops has been contentious. This may be, in part, a consequence of poorly agreed upon study objectives. Whole-food animal-feeding studies have been postulated to be useful in detecting both expected and unexpected effects on the composition of genetically modified crops. While the justification of animal feeding studies to detect unexpected effects may be inadequately supported, there may be better justification to conduct such studies in specific cases to investigate the consequences of expected compositional effects including expression of transgenic proteins. Such studies may be justified when (1) safety cannot reasonably be predicted from other evidence, (2) reasonable hypothesis for adverse effects are postulated, (3) the compositional component in question cannot be isolated or enriched in an active form for inclusion in animal feeding studies, and (4) reasonable multiples of exposure can be accomplished relative to human diets. The study design for whole-food animal-feeding studies should be hypotheses-driven, and the types of data collected should be consistent with adverse effects that are known to occur from dietary components of biological origin.
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Affiliation(s)
- Rod A Herman
- Dow AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN 46268, United States.
| | - Ricardo Ekmay
- Dow AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN 46268, United States.
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Yu HL, Ruan WW, Cao MJ, Cai QF, Shen HW, Liu GM. Identification of physicochemical properties of Scylla paramamosain allergen, arginin kinase. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2013; 93:245-253. [PMID: 22674459 DOI: 10.1002/jsfa.5748] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 04/02/2012] [Accepted: 04/25/2012] [Indexed: 06/01/2023]
Abstract
BACKGROUND Arginine kinase (AK) is expressed in a wide variety of species, including human food sources (seafood) and pests (cockroaches and moths), and has been reported as a novel allergen. However, there has been little research on the allergenicity of AK in crustaceans. In this study the physicochemical properties of AK from mud crab (Scylla paramamosain) were investigated. RESULTS Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis, immunoblotting and inhibition enzyme-linked immunosorbent assay revealed that purified AK was unstable in thermal processing and in acid buffer. Under simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) conditions, purified AK was much more readily degraded by pepsin than by trypsin or chymotrypsin. The unpurified AK in crab myogen degraded more markedly than purified AK. In addition, in two-phase gastrointestinal digestion, AK was rapidly degraded by pepsin but resistant to trypsin and chymotrypsin digestion, while tropomyosin derived from mud crab was resistant to pepsin digestion but digested readily by trypsin or chymotrypsin. Further study of serum samples obtained from crab-allergic human patients indicated that the allergenicity of AK was markedly reduced by digestion with SGF but not SIF. CONCLUSION AK is an important food allergen despite its unstable physicochemical properties of digestibility.
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Affiliation(s)
- Hui-Lin Yu
- College of Biological Engineering, The Key Laboratory of Science and Technology for Aquaculture and Food Safety, Jimei University, 43 Yindou Road, Xiamen 361021, Fujian, China
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