Assessing Genetically Modified Crops to Minimize the Risk of Increased Food Allergy: A Review

Abstract

The first genetically modified (GM) crops approved for food use (tomato and soybean) were evaluated for safety by the United States Food and Drug Administration prior to commercial production. Among other factors, those products and all additional GM crops that have been grown commercially have been evaluated for potential increases in allergenic properties using methods that are consistent with the current understanding of food allergens and knowledge regarding the prediction of allergenic activity. Although there have been refinements, the key aspects of the evaluation have not changed. The allergenic properties of the gene donor and the host (recipient) organisms are considered in determining the appropriate testing strategy. The amino acid sequence of the encoded protein is compared to all known allergens to determine whether the protein is a known allergen or is sufficiently similar to any known allergen to indicate an increased probability of allergic cross-reactivity. Stability of the protein in the presence of acid with the stomach protease pepsin is tested as a risk factor for food allergenicity. In vitro or in vivo human IgE binding are tested when appropriate, if the gene donor is an allergen or the sequence of the protein is similar to an allergen. Serum donors and skin test subjects are selected based on their proven allergic responses to the gene donor or to material containing the allergen that was matched in sequence. While some scientists and regulators have suggested using animal models, performing broadly targeted serum IgE testing or extensive pre- or post-market clinical tests, current evidence does not support these tests as being predictive or practical. Based on the evidence to date, the current assessment process has worked well to prevent the unintended introduction of allergens in commercial GM crops.

Importance of Databases in Experimental and Clinical Allergology

“…Although it may seem outdated to classify organisms capable of inducing allergic reactions rather than their molecular structures, the still expanding knowledge on allergenic sources is a continuous challenge for achieving the most comprehensive list of allergen molecules. It is also important to keep in mind that the emergence of allergy as a problem in developing countries and the globalization in terms of mobility of people and goods create new allergenic sources [23,24,25] and new routes of exposure [26]. Thus, a reliable database resource for allergenic organisms should be established as well.…”

Medical Doctors’ Perceptions of Genetically Modified Foods

“…Another harmful effect is the occurrence of antibiotic-resistant infections as a result of transference of genes to pathogenic micro-organisms when marker genes used in gene transference are used together with original gene. Moreover, it has been shown that foreign DNAs used as food can be transferred to cells and thus may cause genetic defects human DNA [12]. In addition to these, there are studies showing that GM foods would decrease biological diversity in the future years [10,13].…”

Practical and predictive bioinformatics methods for the identification of potentially cross‐reactive protein matches

“…Regulatory bodies in various countries differ in their requirements for evaluating the safety or potential risks of products that include these newly introduced proteins. The US, EU, and many other countries have now implemented requirements for evaluating the potential allergenicity of such products [1]. The primary focus, either elaborated or implied, is on preventing the transfer of a known allergen, or a protein sufficiently similar to a known allergen that it may trigger allergic crossreactions.…”