Introduction Veritiesof genetically modified cotton ,maize, soybean and canola contain genesencoding specific proteins to dramatically improve farming efficiency byimproving reduced tillage with herbicide tolerance or to reduce the need ofchemical pesticide.Internationalguidelines for the evaluation of the potential allergenicity of GM crops weredeveloped by Codex Alimentarious Commission of the Food and AgricultureOrganization and World Health Organization of UN.
The end point of assessment is the conclusion that newlyintroduced protein is an allergen.Backgroundwith development of genetically modified crop plants there has been a growinginterest in the approaches available to assess the potential allergencity ofexpressed proteins , informative data can be generated using Animal models.Advancesin biotechnology has resulted in increasing number of genetically engineered food , and among thesesoybeans is one of the most widespread. Soybean is one of the major source of protein in human andanimal nutrition and has also been well characterized as a major allergensource.
Genetically Modified Soybean A genetically modified soybean is a soybean that has has DNA introduced intoit using genetic engineering techniques.1 Monsant introduce first genetically modified soybean. In 2014,90.7 million hectares of Genetically Modified soybean was produced all over theworld .2Genetic makeup of soybeanmake it useful . As we all know thatthis world need high yield in less time so people adopt those methods whichproduce high yield. These phases becameknown as the first and second generation of genetically modified (GM) foods.
,.3RoundupReady SoybeanMonsanto produced Roundup Ready Soybeans (The first variety wasalso known as GTS 40-3-2 (OECD UI: MON-04032-6)) are a group of genetically engineered varieties of glyphosate-resistant soybeans.He found that in plant damage is cause by Glyphosate interferingwith the synthesis of the essential amino acids phenylalanine, tyrosine and tryptophan. Plants and microorganisms make these amino acids with an enzyme5-enolpyrovylshikimate-3phosphate (EPSPS).4EPSPSabsent in Animals.
, which obtain aromatic amino acids from their food.5 The plasmid with EPSPS was inserted into soybean germplasm witha gene gun by scientists at Monsantoand Asgrow.67 The patent of firstgeneration of Roundup Ready soybeans turn to end in March 2015.8 Allergy assessment:The main achievement of the allergenicity assessment is to minimize therisk that the genetically modified are more allergenic then the food producedfrom non gm crop.
The main focus is on the safety of any newly expressedprotein. If the expressed protein is already known as an allergn, or similarmay cause the allergic cross reaction if it exposed or consumed by theindividuals who have already experience the serious allergenic reactions. thewide spread of the food allergy is still not known Different surveys shows that 1-3 percent ofAdults are affected with allergy and 6-8 percent of children Apart from these 4percent of US population having IgE-mediated food allergies9.Up-to-date study in France indicated approximately 3.5%of their population has food allergy 10.
Food allergy is an adverse reaction of the human immune systemto an otherwise harmless food component and the prevalenceof food allergy in Europe is up to 3% according to the EAACI foodallergy and anaphylaxis guidelines group (Nwaru et al., 2014). Foodallergy develops in two phases. In the first phase susceptible subjectsbecome sensitised to specific food proteins after dietaryexposure, or possibly via other routes of exposure (inhalationand/or skin contact).
This may result in the production of specific IgE tothe food protein (Johnstonet al., 2014; Kimber and Dearman, 2002).When sensitised subjects subsequently encounter the respectiveallergen(s) again, cellular bound specific IgE will recognize theallergensand an allergic reaction may be elicited.
Allergic symptomsmay vary considerably and can range from mild, local and transienteffects to potential fatal reactions like systemic anaphylaxis(Sicherer and Sampson, 2014;Sicherer and Wood, 2013).Generally, food allergens are proteins but the vast majority offood proteins are weak or virtually non-allergenic (Metcalfe et al.,1996; Radauer et al., 2008).
Most cases (90%) of food allergic reactionsare caused by a limited range of products; milk, egg, peanut,tree nuts, fish, soy, wheat and crustaceans (Boyce et al., 2010; Hefleet al., 1996; Young et al., 1994). Furthermore, the manifestations offood allergies can be dependent on geography, dietary habits, foodpreparation and age at which food is first consumed (Lucas et al.,2004).
It is therefore possiblethat a food product that was not reportedto be common or known as allergenic in Asia can be anallergenic food in Europe, for example kiwi fruit (Lucas et al., 2004).Another example is the allergy to peach, a member of the Rosaceafamily which is attributed to birch pollen in Central and NorthernEurope (Pru p 1, the Bet v 1 homologue, PR-10) and leads to mildreactions (oral allergy syndrome), while in the Mediterraneanareaswhere birch trees are less common, peach allergy may result fromsensitisation to Pru p 3 (lipid transfer protein, LTP) and/or Prup 4(profilin) which more commonly leads to severe allergicreactions(Andersen et al., 2011).At the moment, novel foods such as insects and rapeseed areentering the market without a proper allergenicity riskassessment.For mealworms, larval stage of the yellow mealworm beetle, it wasrecently demonstrated in a double blind placebo controlled foodchallenge (DBPCFC) that 87% of a shrimp allergic patientspopulationshowed allergic reaction upon eating Yellow mealworm andthat de novo sensitisation to Yellow mealworm proteins ispossible(Broekman et al., 2015a) (Broekman, JACI, in press). In case ofrapeseed, which was formally in use in the EU only in the form ofrapeseed oil, the EFSA panel concluded, that a risk ofsensitisationto rapeseed protein isolate cannot be excluded and that it islikelythat rapeseed will trigger allergic reactions in mustard allergicsubjects (EFSA NDA Panel (EFSA NDA Panel, 2013)).
This conclusionwas based on a food challenge and a skin prick tests with crushedrapeseed (not protein isolate) in atopic Finnish children withatopicdermatitis and suspected food allergies. 10.9% of the childrenshowed sensitivity in the SPT and 89% of these children reactedpositive in the food challenge. Cross reactivity with mustardseedswas demonstrated using IgE binding tests with serum formmustard allergic patients. Furthermore, structural homology of 95%of seed storage proteins of various members of the brassicaceae,incl. mustard was shown.
In this assessment, clinically relevantstudies were performed with crushed rapeseed but not withrapeseed protein isolate. In the latter, a higher proteinconcentrationcan be expected and furthermore, the effect of processing wasnot taken into account. Other novel food dossiers submitted in thelast five years for approval by the EFSA (e.g. Chia seed,Lentinusedodos and alfalfa) were lacking properly conducted clinicallyrelevant tests (e.
g. SPT, or basophil activation tests (BAT)) andinmost cases no formal proof of absence of allergenicity usingdoubleblind placebo controlled food challenge (DBPCFC) was given, norwas the effect of processing or the sensitising potency tested (EFSANDA Panel, 2009, 2010a, 2010b). Food challenges are essential fordetermining if IgE binding measured with techniques such asimmunoblot, BAT and SPT is clinically relevant.
IgE binding or IgEcross reactivity does not automatically indicate that an allergicreaction will occur. For instance, some proteins have crossreactivecarbohydrate determinants (mostly found in plants) that bind toIgE but do not elicit an allergic reaction (Mari et al., 1999).Furthermore, cross reactivity between taxonomically related foods,such as the legume family (peanut, soy, lupine, white bean) doesnot automatically indicate clinical cross reactivity (Peeters et al.,2007). Ib_a?ez et al.
showed that whitebean and overall greenbean are well tolerated by children allergic to other legumes(Ibanez et al., 2003).It is in the interest of the producer of novel food products topredict allergenicity in an early stage of product development toavoid withdrawal of the novel food from the food market afterintroduction.
For this reason, it is necessary to assess theallergenicpotential of novel foods before a well-informed decision can bemade on the allergenic potential of a novel food and to guide theimplementation of risk managements tools such as labelling. Riskmanagement aspects are not addressed in this paper.In this paper the current risk assessment strategy and guidelineswill be discussed and a conceptual strategy is suggested, aimed togive better guidance in how to assess the allergenicity of novelfoodproteins and protein sources.Current strategy andguidelines for Allergy Assessment There is no valid method for allergy assessment the safetyevaluation mainly focuses on 1)Evaluation of the source of the gene2)Sequence homology with known allergens3)Binding to IgE from allergic individuals4) Stability of theprotein in a pepsin resistance test.IgE Binding test Specific serum screening is recommended by Codex and EFSAguidelinesin cases where the source of the gene/protein commonly causes allergies, orwhen there is a high degree of sequence homologyof the protein (>35% homology) to a knownallergen.In a specific serumscreen binding of the transgenic protein with sera from patients with aclinical food allergy to a specific allergen/food is tested to determine whether the transgenicprotein is not cross reactive with a known food allergen.
Pepsinresistance test . Resistance to pepsin is proposed as a criterion for a protein tobeconsidered as a potential allergen. However, it has beenestablishedthat no absolute correlation exists (Bannon et al., 2002;Manchestero, 2013; Moreno, 2007) between pepsin resistanceand allergenicity and there is no internationally acceptedprotocolavailable to perform such in vitro digestibility tests.Improvementand good guidance for the interpretation of pepsin resistance testand validation of the test with allergens and (virtually)nonallergensis currently under review of the EFSA GMO panel (EFSAworkshop June 17th Brussels