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Introduction

Verities
of genetically modified cotton ,maize, soybean and canola contain genes
encoding specific proteins to dramatically improve farming efficiency by
improving reduced tillage with herbicide tolerance or to reduce the need of
chemical pesticide.

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International
guidelines for the evaluation of the potential allergenicity of GM crops were
developed by Codex Alimentarious Commission of the Food and Agriculture
Organization and World Health Organization of UN. The end point of  assessment is the conclusion that newly
introduced protein is an allergen.

Background
with development of genetically modified crop plants there has been a growing
interest in the approaches available to assess the potential allergencity of
expressed proteins , informative data can be generated using Animal models.

Advances
in biotechnology has resulted in increasing number of  genetically engineered food , and among these
soybeans is one of the most widespread. Soybean is one of  the major source of protein in human and
animal nutrition and has also been well characterized as a major allergen
source. 

Genetically Modified Soybean 

A genetically modified soybean is a soybean that has has DNA introduced into
it 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 the
world .2

Genetic makeup of soybean
make it useful  . As we all know that
this world need high yield in less time so people adopt those methods which
produce high yield.   These phases became
known as the first and second generation of genetically modified (GM) foods.,.3

Roundup
Ready Soybean

Monsanto produced Roundup Ready Soybeans (The first variety was
also 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 interfering
with the synthesis of the essential amino acids phenylalanine, tyrosine and tryptophan.  

Plants and microorganisms make these amino acids with an enzyme
5-enolpyrovylshikimate-3phosphate (EPSPS).4EPSPS
absent in Animals., which obtain aromatic amino acids from their food.5

 The plasmid with EPSPS was inserted into soybean germplasm with
a gene gun by scientists at Monsanto
and Asgrow.67 The patent of first
generation of Roundup Ready soybeans turn to end in March 2015.8

 Allergy assessment:

The main achievement of the allergenicity assessment is to minimize the
risk that the genetically modified are more allergenic then the food produced
from non gm crop. The main focus is on the safety of any newly expressed
protein. If the expressed protein is already known as an allergn, or similar
may cause the allergic cross reaction if it exposed or consumed by the
individuals who have already experience the serious allergenic reactions. the
wide spread of the food allergy is still not known  Different surveys shows that 1-3 percent of
Adults are affected with allergy and 6-8 percent of children Apart from these 4
percent 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 system

to an otherwise harmless food component and the prevalence

of food allergy in Europe is up to 3% according to the EAACI food

allergy and anaphylaxis guidelines group (Nwaru et al., 2014). Food

allergy develops in two phases. In the first phase susceptible subjects

become sensitised to specific food proteins after dietary

exposure, or possibly via other routes of exposure (inhalation
and/

or skin contact). This may result in the production of specific IgE to

the food protein (Johnston
et al., 2014; Kimber and Dearman, 2002).

When sensitised subjects subsequently encounter the respective

allergen(s) again, cellular bound specific IgE will recognize the
allergens

and an allergic reaction may be elicited. Allergic symptoms

may vary considerably and can range from mild, local and transient

effects to potential fatal reactions like systemic anaphylaxis

(Sicherer and Sampson, 2014;
Sicherer and Wood, 2013).

Generally, food allergens are proteins but the vast majority of

food proteins are weak or virtually non-allergenic (Metcalfe et al.,

1996; Radauer et al., 2008). Most cases (90%) of food allergic reactions

are caused by a limited range of products; milk, egg, peanut,

tree nuts, fish, soy, wheat and crustaceans (Boyce et al., 2010; Hefle

et al., 1996; Young et al., 1994). Furthermore, the manifestations of

food allergies can be dependent on geography, dietary habits, food

preparation and age at which food is first consumed (Lucas et al.,

2004). It is therefore possible
that a food product that was not reported

to be common or known as allergenic in Asia can be an

allergenic food in Europe, for example kiwi fruit (Lucas et al., 2004).

Another example is the allergy to peach, a member of the Rosacea

family which is attributed to birch pollen in Central and Northern

Europe (Pru p 1, the Bet v 1 homologue, PR-10) and leads to mild

reactions (oral allergy syndrome), while in the Mediterranean
areas

where birch trees are less common, peach allergy may result from

sensitisation to Pru p 3 (lipid transfer protein, LTP) and/or Pru
p 4

(profilin) which more commonly leads to severe allergic
reactions

(Andersen et al., 2011).

At the moment, novel foods such as insects and rapeseed are

entering the market without a proper allergenicity risk
assessment.

For mealworms, larval stage of the yellow mealworm beetle, it was

recently demonstrated in a double blind placebo controlled food

challenge (DBPCFC) that 87% of a shrimp allergic patients
population

showed allergic reaction upon eating Yellow mealworm and

that de novo sensitisation to Yellow mealworm proteins is
possible

(Broekman et al., 2015a) (Broekman, JACI, in press). In case of

rapeseed, which was formally in use in the EU only in the form of

rapeseed oil, the EFSA panel concluded, that a risk of
sensitisation

to rapeseed protein isolate cannot be excluded and that it is
likely

that rapeseed will trigger allergic reactions in mustard allergic

subjects (EFSA NDA Panel (EFSA NDA Panel, 2013)). This conclusion

was based on a food challenge and a skin prick tests with crushed

rapeseed (not protein isolate) in atopic Finnish children with
atopic

dermatitis and suspected food allergies. 10.9% of the children

showed sensitivity in the SPT and 89% of these children reacted

positive in the food challenge. Cross reactivity with mustard
seeds

was demonstrated using IgE binding tests with serum form

mustard 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 relevant

studies were performed with crushed rapeseed but not with

rapeseed protein isolate. In the latter, a higher protein
concentration

can be expected and furthermore, the effect of processing was

not taken into account. Other novel food dossiers submitted in the

last five years for approval by the EFSA (e.g. Chia seed,
Lentinus

edodos and alfalfa) were lacking properly conducted clinically

relevant tests (e.g. SPT, or basophil activation tests (BAT)) and
in

most cases no formal proof of absence of allergenicity using
double

blind placebo controlled food challenge (DBPCFC) was given, nor

was the effect of processing or the sensitising potency tested (EFSA

NDA Panel, 2009, 2010a, 2010b). Food challenges are essential for

determining if IgE binding measured with techniques such as

immunoblot, BAT and SPT is clinically relevant. IgE binding or IgE

cross reactivity does not automatically indicate that an allergic

reaction will occur. For instance, some proteins have cross
reactive

carbohydrate determinants (mostly found in plants) that bind to

IgE 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) does

not automatically indicate clinical cross reactivity (Peeters et al.,

2007). Ib_a?ez et al. showed that white
bean and overall green

bean 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 to

predict allergenicity in an early stage of product development to

avoid withdrawal of the novel food from the food market after

introduction. For this reason, it is necessary to assess the
allergenic

potential of novel foods before a well-informed decision can be

made on the allergenic potential of a novel food and to guide the

implementation of risk managements tools such as labelling. Risk

management aspects are not addressed in this paper.

In this paper the current risk assessment strategy and guidelines

will be discussed and a conceptual strategy is suggested, aimed to

give better guidance in how to assess the allergenicity of novel
food

proteins and protein sources.

Current strategy and
guidelines for Allergy Assessment 

There is no valid method for allergy assessment the safety
evaluation mainly focuses on 

1)
Evaluation of the source of the gene

2)
Sequence homology with known allergens

3)
Binding to IgE from allergic individuals

4) Stability of the
protein in a pepsin resistance test.

IgE Binding test

Specific serum screening is recommended by Codex and EFSA

guidelines
in cases where the source of the gene/protein commonly causes allergies, or
when there is a high degree of sequence homologyof the protein (>35% homology) to a known

allergen.
In a specific serum
screen binding of the transgenic protein with sera from patients with a
clinical food allergy to a specific allergen/food is tested to determine whether the transgenic
protein is not cross reactive with a known food allergen.

Pepsin
resistance test .

 

Resistance to pepsin is proposed as a criterion for a protein to
be

considered as a potential allergen. However, it has been
established

that no absolute correlation exists (Bannon et al., 2002;

Manchestero, 2013; Moreno, 2007) between pepsin resistance

and allergenicity and there is no internationally accepted
protocol

available to perform such in vitro digestibility tests.
Improvement

and good guidance for the interpretation of pepsin resistance test

and validation of the test with allergens and (virtually)
nonallergens

is currently under review of the EFSA GMO panel (EFSA

workshop June 17th Brussels

 

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