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FOOD GENETICALLY MODIFIED
The BIOTECHNOLOGIES are all technologies that use living organisms, or parts of them in order
to produce commercial quantities of products useful to human beings, to improve plants and
animals or to develop microorganisms for specific uses.
They exist from thousands of years, and are divided into two types:
•
TRADITIONAL: Production of fermented foods and beverages, selection of seeds and
animals best suited to the uses for animal farming;
•
INNOVATIVE: Discovery of microorganisms, discovery of antibiotics, birth of genetic
engineering.
Genetically modified organisms (GMOs) can be defined as organisms (i.e. plants, animals or
microorganisms) in which the genetic material (DNA) has been altered in a way that does not
occur naturally by mating and/or natural recombination. The technology is often called “modern
biotechnology” or “gene technology”, sometimes also “recombinant DNA technology” or
“genetic engineering”. It allows selected individual genes to be transferred from one organism
into another, also between nonrelated species. Foods produced from or using GM organisms are
often referred to as GM foods.
Many important application of recombinant DNA technology is in pharmacology, as an example
for the production of insulin. Insulin is produced only from higher organisms, in small amounts;
these technologies make it possible to carry the genes responsible for insulin production in
bacterial cells instead. Bacterial cells can be cultivated, producing large amounts of insulin (see
Figure below).
Figure: Bacteria that produce human INSULIN.
Main GMO applications:
•
•
•
medicin (insulin, vaccines)
ecology (bioremediation, super-bacteria against ecological disasters can be used in case
of oil spills from tankers, as the modified bacteria are able to “eat” the oil. This is one of
the major results of "bioremediation", the use of biotechnology for environmental
recovery).
agribusiness and zoo-technical sectors
Genetically modified (GM) foods are foods derived from organisms whose genetic material (DNA)
has been modified in a way that does not occur naturally, e.g. through the introduction of a gene
from a different organism. Most existing genetically modified crops have been developed to
improve yield, through the introduction of resistance to plant diseases or of increased tolerance
of herbicides.
The importance of genetically modify an organism lies in the fact that a better crop yield,
especially under harsh conditions, is possible. Herbicide or disease resistance is another goal of
GM plant. Two important transgenes have been widely introduced into crop plants. The Bt gene,
from Bacillus thuringiensis, produces a toxin that protects against caterpillars, reducing
applications of insecticides and increasing yields. The glyphosate resistance gene protects food
plants against the broad-spectrum herbicide Roundup® (by Monsanto), which efficiently kills
invasive weeds in the field. The major advantages of the "Roundup Ready®” system include
better weed control, reduction of crop injury, higher yield, and lower environmental impact than
traditional herbicide systems.
Future researches on genetic modification could be aimed at altering the nutrient content of
food, reducing its allergenic potential, or improving the efficiency of food production systems.
All GM foods should be assessed before being allowed on the market. FAO/WHO Codex
guidelines exist for risk analysis of GM food.
Figure 1. Numbers of Consultations on Genetically Engineered Crops
From http://www.who.int/ web site
RISKS and BENEFITS of GMOs
The interactions between transgene and DNA in which it is placed are not predictable nor
controllable. Equally unpredictable are the effects of transgenic organisms massively
disseminated in the environment.
RISKS:
•
pollution or gene biopollution
•
bioinvasion
•
chemical pollution (from herbicides)
•
development of viral species hybrid
•
reduce the use of pesticides
•
vary the nutritional and organoleptic characteristics for a better diet
•
increase the productivity of plants
BENEFITS
To understand what Genetically Modified Organisms or GMOs are, let’s first review what DNA is.
Within the tissues of the plant are cells. Within the cell is the nucleus. Within that are
chromosomes composed of the DNA molecule, which in turn is made up of a sequence of base
pairs. A simplistic description is that sequence of the genes in the DNA determine the sequence
in the RNA, which then determines the sequence of the building blocks of proteins, called amino
acids. These proteins can determine a particular trait or characteristic (phenotype).
Using genetic engineering, scientists take genes from bacteria, viruses or other sources and force
them into the DNA of a plant. There are 5 steps (see below). First, they isolate the gene that they
want to insert and, then, change it so that it works in plants. They prepare plant cells to be
inserted. Insertion is often done using a gene gun, where they coat tiny particles of gold or
tungsten with genes and then shoot them into a plate of cells. Alternatively, they can use bacteria
to infect plants with the foreign gene. Once the gene gets into the DNA of the plant cell, the cell
is cloned (using tissue culture) into a full plant. All but one of these steps contain scientific
uncertainties and risks for health and the environment.
1. Isolate a gene with a desired trait
2. Change the gene so it will works in plants
3. Prepare plant cells or tissue
4. Transform plant cells using a gene gun or bacteria infection method
5. Re-grow cells to plants via tissue culture (cloning).
Scheme of gene transfer by the Agrobacterium tumefaciens method:
In the Agrobacterium tumefaciens method the first step is the isolation of the gene to be
transferred, separately from the rest of the DNA by a restriction enzyme. The restriction enzyme
is able to break a DNA fragment in specific sites containing a gene with promoter and stop signal.
The gene is then introduced into the DNA of a plasmid of Agrobacterium (a plasmid is a small
and circular DNA molecule within a cell that is physically separated from a chromosomal DNA
and can replicate independently). Subsequently, there is the transfer of the plasmid, which
carries the gene, in a germ cell of another plant species, obtaining a new cell with the desired
genetic characteristics. The final phase is the duplication of the modified cells (see the Scheme
reported above).
Food
Properties of GM
Modification
Variety
Cotton
(cottonseed oil)
Soybeans
Corn
% Modified
in the World
Pest-resistant
cotton
Bt crystal protein
gene
49%
added/transferred
into plant genome
Resistant
to
Herbicide resistant
glyphosate
glucofosinate
herbicides
or
gene taken from
bacteria inserted
into soybean
Resistant
glyphosate
glucofosinate
to
or
New genes, some
from the bacterium
Bacillus
herbicides.
Insects resistance
via producing Bt
77%
26%
thuringensis,
added/transferred
into plant genome
proteins. Vitaminenriched
corn
derived from South
Africa white corn
Canola
Resistant
to
herbicides
(glyphosate
or
glucofosinate),
high laurate canola
New
genes
added/transferred
into plant genome
21%
Why are GM foods produced?
GM foods are developed – and marketed – because there is some perceived advantage either to
the producer or consumer of these foods.
One of the objectives for developing plants based on GM organisms is to improve crop
protection. The GM crops currently on the market are mainly aimed at an increased level of crop
protection through the introduction of resistance against plant diseases caused by insects or
viruses or through increased tolerance towards herbicides.
Resistance against insects is achieved by incorporating into the food plant the gene for toxin
production from the bacterium Bacillus thuringiensis (Bt). This toxin is currently used as a
conventional insecticide in agriculture and is safe for human consumption. GM crops that
inherently produce this toxin have been shown to require lower quantities of insecticides in
specific situations, e.g. where pest pressure is high.
Virus resistance is achieved through the introduction of a gene from certain viruses which cause
disease in plants. Virus resistance makes plants less susceptible to diseases caused by such
viruses, resulting in higher crop yields.
Herbicide tolerance is achieved through the introduction of a gene from a bacterium conveying
resistance to some herbicides. In situations where weed pressure is high, the use of such crops
has resulted in a reduction in the quantity of the herbicides used.
Is the safety of GM foods assessed differently from conventional foods?
Generally consumers consider that conventional foods (that have an established record of safe
consumption over the history) are safe. Whenever novel varieties of organisms for food use are
developed using the traditional breeding methods that had existed before the introduction of
gene technology, some of the characteristics of organisms may be altered, either in a positive or
a negative way. National food authorities may be called upon to examine the safety of such
conventional foods obtained from novel varieties of organisms, but this is not always the case.
In contrast, most national authorities consider that specific assessments are necessary for GM
foods. Specific systems have been set up for the rigorous evaluation of GM organisms and GM
foods relative to both human health and the environment. Similar evaluations are generally not
performed for conventional foods. Hence there currently exists a significant difference in the
evaluation process prior to marketing for these two groups of food.
The WHO Department of Food Safety and Zoonoses aims at assisting national authorities in the
identification of foods that should be subject to risk assessment and to recommend appropriate
approaches to safety assessment.
Should national authorities decide to conduct safety assessment of GM organisms, WHO
recommends the use of Codex Alimentarius guidelines.
How is a safety assessment of GM food conducted?
The safety assessment of GM foods generally focuses on:
(a) direct health effects (toxicity)
(b) potential to provoke allergic reaction (allergenicity)
(c) specific components thought to have nutritional or toxic properties
(d) the stability of the inserted gene
(e) nutritional effects associated with genetic modification
(f) any unintended effects which could result from the gene insertion.
What are the main issues of concern for human health?
ALLERGENICITY
As a matter of principle, the transfer of genes from commonly allergenic organisms to nonallergic organisms is discouraged unless it can be demonstrated that the protein product of the
transferred gene is not allergenic. While foods developed using traditional breeding methods are
not generally tested for allergenicity, protocols for the testing of GM foods have been evaluated
by the Food and Agriculture Organization of the United Nations (FAO) and WHO. No allergic
effects have been found relative to GM foods currently on the market.
GENE TRANSFER
Gene transfer from GM foods to cells of the body or to bacteria in the gastrointestinal tract would
cause concern if the transferred genetic material adversely affects human health. This would be
particularly relevant if antibiotic resistance genes, used as markers when creating GMOs, were
to be transferred. Although the probability of transfer is low, the use of gene transfer technology
that does not involve antibiotic resistance genes is encouraged.
OUTCROSSING
The migration of genes from GM plants into conventional crops or related species in the wild
(referred to as “outcrossing”), as well as the mixing of crops derived from conventional seeds
with GM crops, may have an indirect effect on food safety. Cases have been reported where GM
crops approved for animal feed or industrial use were detected at low levels in the products
intended for human consumption. Several countries have adopted strategies to reduce mixing,
including a clear separation of the fields within which GM crops and conventional crops are
grown.
How is a risk assessment for the environment performed?
Environmental risk assessments cover both the GMO concerned and the potential receiving
environment. The assessment process includes evaluation of the characteristics of the GMO and
its effect and stability in the environment, combined with ecological characteristics of the
environment in which the introduction will take place.
What are the issues of concern for the environment?
Issues of concern include: the capability of the GMO to escape and potentially introduce the
engineered genes into wild populations; the persistence of the gene after the GMO has been
harvested; the susceptibility of non-target organisms (e.g. insects which are not pests) to the
gene product; the stability of the gene; the reduction in the spectrum of other plants including
loss of biodiversity; and increased use of chemicals in agriculture.
The main negative aspect of Genetically Engineered Foods could be related to environmental
concerns.
UNINTENTIONAL ENVIRONMENTAL EFFECTS
◦
Creation of pesticide-resistant insects
◦
affect beneficial insects (as monarch butterfly)
◦
development of “superweeds”, “superbugs”
Control of Food Production
◦ GMO plants with gene to produce sterile seeds
◦ Biotech firms with too much control? (Monsanto, Calgene)
Are GM foods safe?
Different GM organisms include different genes inserted in different ways. This means that
individual GM foods and their safety should be assessed on a case-by-case basis and that it is not
possible to make general statements on the safety of all GM foods.
GM foods currently available on the international market have passed safety assessments and
are not likely to present risks for human health. In addition, no effects on human health have
been shown as a result of the consumption of such foods by the general population in the
countries where they have been approved. Continuous application of safety assessments based
on the Codex Alimentarius principles and, where appropriate, adequate post market
monitoring, should form the basis for ensuring the safety of GM foods.
Benefits of Genetically Engineered Foods:
Improved nutritional quality of plants
◦
“golden rice” (rice with Vitamin A gene)
◦
rice with β-carotene gene
◦
improved protein quality & quantity
◦
higher in vitamins
Improved sensory properties
◦
Tomato and strawberry flavor & texture
Health Issues
◦
Lack of long term feeding trials (animal studies, human studies)
◦
Food allergies
◦
Labeling Issue (consumer has the right to know)
How are GM foods regulated nationally?
EU legislation foresees that no GMO can be cultivated in the EU if it has not received a prior
authorisation, following a thorough risk assessment, which involves the national evaluation
agencies and the European Food Safety Authority (EFSA), in order to ensure safety for human
and animal health and for the environment.
While cultivation is recognised to be an issue with strong national or local dimensions, current
EU legislation on GMOs offers limited possibilities to Member State to decide on GMO cultivation
on their territory. For the moment, Member States can only restrict or ban the cultivation of
GMOs by adopting safeguard clauses where new serious risks to human health, animal health
and the environment are identified after the GMO has been authorised.
In 2009, 13 Member States asked the Commission for more flexibility to decide not to cultivate
GMOs on their territory. This is why, in 2010, the Commission adopted a proposal to the
European Parliament and to the Council to offer additional possibilities to Member States to ban
or restrict the cultivation of GMOs on part of or all their territory, based on their national
circumstances, and without affecting the EU authorisation system.
In July 2011, the European Parliament issued a positive first reading opinion with amendments
and after several years, the Council adopted on 12 June 2014 a political agreement which will
allow the co-legislators to get one step closer towards the adoption of the proposal.
Early regulations concerning genetically modified organisms (GMOs) in Italy were aimed at
deterring their development in the country. However, the flow of European regulations from
the late 1990s onward changed the legal framework for regulating GMOs. Pursuant to European
Union (EU) Directive Nos. 219 and 220 of 1990, and 259 of 1997, Italy cannot limit the
importation of GMOs, which are already approved at the European level.
In 2000, Italy for the first time enacted legislation to ban the use of certain GMOs used in foods
for human consumption.
Two years later legislation imposed a moratorium on the mixture of GMO and non-GMO
products. Finally, several pieces of legislation enacted since early 2003 have sought to more
strictly regulate GMO experimentation, use, mixtures, and release into the environment,
particularly concerning GMOs used for food crops.
Thus, at this point, GMO cultivation is currently permitted in Italy, but subject to stringent
regulations concerning the assessment of its impacts on human and animal health, and the
environment.
In Italy, the introduction of GMOs has generated serious concerns related to food safety and
consumer protection.
Their subsequent impact on the food chain is a very controversial matter. Another common
objection to GMOs arises over the dangers of GMOs escaping from their confined environments
and mixing with populations living under natural conditions.
Overall, despite the European GMO regulations, the general public has strongly opposed the
introduction of GMOs into Italy, and this opposition has had an impact on Italian legislation since
at least 2000.
Only recently, on July 12, 2013, the Italian government banned the cultivation of Monsanto
Corn 810 (Mon810), as the first of a series of measures designed to define a new more
restrictive framework for the cultivation of GMOs in Italy.
However, fresh opinion polls indicate that the Italian public is now adopting a slightly more proGMO stance.
The complexity of the ethical and economic questions involved in the production of GMOs has
caused the EU to regulate this field through Directive Nos. 90/219, 259/97, and 2001/18, which
replaced Directive 90/220.
As a consequence of these directives, Italy may neither limit the importation of GMOs authorized
at the European level, nor prohibit their cultivation for reasons other than those scientifically
supported.
European GMO legislation, which rests on the PRECAUTIONARY PRINCIPLE (the marketing of a
product is made after a risk assessment), comprises the following instruments:
Regulation (EC) No. 1829/2003 of the European Parliament and of the Council of 22
September 2003 on genetically modified food and feed
Regulation (EC) No. 1830/2003 of the European Parliament and of the Council of 22
September 2003 concerning the traceability and labeling of genetically modified
organisms and the traceability of food and feed products produced from genetically
modified organisms and amending Directive 2001/18/EC
Directive 2001/18/EC of the European Parliament and of the Council of 12 March 2001
(amended by Regulation (EC) No. 1830/2003) on the deliberate release into the
environment of genetically modified organisms and repealing Council Directive
90/220/EEC (which had required producers to demonstrate to authorities that a new
product abided by certain security standards)
Commission Recommendation 2003/556/EC of 23 July 2003 on guidelines for the
development of national strategies and best practices to ensure the coexistence of
genetically modified crops with conventional and organic farming
GMO in Italy
The first attempt to block the entry of GMOs into Italy took place in 2000 with the issuance by
the President of the Council of Ministers of the Decreto Amato, which banned the use of foods
derived from GMO Corn 4. This provision was adopted pursuant to a safeguard clause included
in European Regulation 258/97, which had authorized the use of GMO Corn 4 at the European
level. The Decreto Amato was repealed (abrogate), however, by a court in 2004 for lack of
evidence that GMO Corn 4 caused a health hazard. In consequence, this GMO may now be freely
cultivated and used in Italy.
Though GM crops are banned from Italian fields, much of the country’s livestock is fed with GM
soy imported from Brazil and Argentina.
On May 21, the Italian Senate unanimously voted against permitting GM crops in the country.
On May 31, GM crop developer Monsanto retreated from production in Europe due to lack of
demand. Products in Italy must be labeled GMO if they are more than 0.9 percent GM—this does
not apply, however, to products derived from animals fed GMOs.
“To think of Italy as a country that is GMO-free is misleading. We do not cultivate [GM crops],
but we use products derived from GM plants.” Fabio Veronesi (President of the Italian Society of
Agricultural Genetics - SIGA).
European Directive 2001/18/EC was implemented in Italy by Legislative Decree No. 224 of
2003. Along with the existing required standards and evaluations for conducting experiments
with GMOs, this Decree mandated the prior assessment of:
(a) the abandonment or replacement of crops that, owing to the impact of GMOs, have become
no longer appropriate or economically convenient, particularly regarding local varieties;
(b) damage to the image of local products and/or the release area and the costs involved to
defend the image;
(c) a change of market patterns caused by products originating in the release area due to the
impossibility of purchasing GMO-free products, or other commercial impacts;
(d) modifications of the landscape with negative impacts on agro-tourism activities; and
(e) abandonment or marginalization of the release area caused by the impairment of agricultural
practices in the area that have become less profitable owing to GMO impacts.
Decree-Law No. 279 of 2004, which was amended and enacted as legislation by Law No. 5 of
2005, provided for equality between different types of agriculture but imposed on the regions
and autonomous provinces a “plan of coexistence” to prevent the commingling of GMO products
and non-GMO products.
The twenty regions (political-administrative divisions) of the country are now free to determine
their own policies concerning the coexistence of GMO and non-GMO agriculture, but to conform
with European regulations they may not prohibit GMO crops altogether. Currently, thirteen of
the regions have issued provisions imposing de facto restrictions on the cultivation of GMOs in
their territories.
In conclusion, GMO cultivation in Italy is taking place at an experimental level only. At the same
time, most of the fodder used on Italian farms is produced from genetically modified soy and
corn imported from the United States, Canada, and Latin America.
After a first phase of development of agro-biotechnologies, where companies were mostly
concentrated in the production of seeds that can increase yields (due to parasite resistance and
herbicide tolerance) and to reduce production costs, in the second phase sector will focus on
high-quality vegetable (fruit and vegetable market).
What happens when GM foods are traded internationally?
One of the biggest stumbling blocks to securing a massive free trade agreement between the
United States and Europe is a sharp disagreement on genetically modified foods.
Much of the corn, soybean, sugar beets and cotton cultivated in the United States today contains
plants whose DNA was manipulated in labs to resist disease and drought, ward off insects and
boost the food supply. Though common in the U.S., they are largely banned in the 28-nation
European Union.
The Codex Alimentarius Commission (Codex) is the joint FAO/WHO intergovernmental body
responsible for developing the standards, codes of practice, guidelines and recommendations
that constitute the Codex Alimentarius, meaning the international food code. Codex developed
principles for the human health risk analysis of GM foods in 2003.
• Principles for the risk analysis of foods derived from modern biotechnology
The premise of these principles sets out a premarket assessment, performed on a case by- case
basis and including an evaluation of both direct effects (from the inserted gene) and unintended
effects (that may arise as a consequence of insertion of the new gene) Codex also developed 3
Guidelines:
• Guideline for the conduct of food safety assessment of foods derived from recombinant-DNA
plants
• Guideline for the conduct of food safety assessment of foods produced using recombinantDNA microorganisms
• Guideline for the conduct of food safety assessment of foods derived from recombinant-DNA
animals
Codex principles do not have a binding effect on national legislation, but are referred to
specifically in the Agreement on the Application of Sanitary and Phytosanitary Measures of the
World Trade Organization (SPS Agreement), and WTO Members are encouraged to harmonize
national standards with Codex standards. If trading partners have the same or similar
mechanisms for the safety assessment of GM foods, the possibility that one product is approved
in one country but rejected in another becomes smaller.
The Cartagena Protocol on Biosafety, an environmental treaty legally binding for its Parties which
took effect in 2003, regulates transboundary movements of Living Modified Organisms (LMOs).
GM foods are within the scope of the Protocol only if they contain LMOs that are capable of
transferring or replicating genetic material. The cornerstone of the Protocol is a requirement that
exporters seek consent from importers before the first shipment of LMOs intended for release
into the environment.
Most studies show genetically modified foods are safe for human consumption, though it is
widely acknowledged that the long-term health effects are unknown. The Food and Drug
Administration (FDA) generally recognized these foods as safe, and the World Health
Organization (WHO) has said no ill health effects have resulted on the international market.
Opponents on both sides of the Atlantic say there has been inadequate testing and regulation.
They worry that people who eat genetically modified foods may be more prone to allergies or
diseases resistant to antibiotics. But they have been hard pressed to show scientific studies to
back up (support) those fears.
GM foods have been a mainstay in the U.S. for more than a decade. Most of the crops are used
for animal feed or in common processed foods such as cookies, cereal, potato chips and salad
dressing.
Europe largely bans genetically engineered foods and has strict requirements on labeling them.
They do allow the import of a number of GM crops such as soy, mostly for animal feed, and
individual European countries have opted to plant these types of crops. Genetically engineered
corn is grown in Spain, though it amounts to only a fraction of European farmland.
The American Medical Association favors mandatory, pre-market safety testing, something that
has not been required by U.S. regulators. The WHO and the U.N. food agency, the Food and
Agriculture Organization, say the safety of genetically modified foods must be evaluated on a
case-by-case basis.
Have GM products on the international market passed a safety assessment?
The GM products that are currently on the international market have all passed safety
assessments conducted by national authorities. These different assessments in general follow
the same basic principles, including an assessment of environmental and human health risk. The
food safety assessment is usually based on Codex documents.
Consumer confidence in the safety of food supplies in Europe has decreased significantly as a
result of a number of food scares that took place in the second half of the 1990s that are
unrelated to GM foods. This has also had an impact on discussions about the acceptability of GM
foods. Consumers have questioned the validity of risk assessments, both with regard to
consumer health and environmental risks, focusing in particular on long-term effects. Other
topics debated by consumer organizations have included allergenicity and antimicrobial
resistance.
Consumer concerns have triggered a discussion on the desirability of labelling GM foods,
allowing for an informed choice of consumers.
GMO LABELING
Europe requires all GM food to be labeled unless GM ingredients amount to 0.9% or less of the
total. The U.S. does not require labels on the view that genetically modified food is not materially
different than non-modified food. Opponents of labeling say it would scare consumers away
from safe foods, giving the appearance that there is something wrong with them.
U.S. activists insist consumers should have the right to choose whether to eat genetically
modified foods and that labeling would offer them that choice, whether the foods are safe or
not. They are pushing for labeling at the state and federal level. Recently, California voters
rejected a ballot initiative that would have required GM food labeling. The legislatures of
Connecticut and Maine have passed laws to label genetically modified foods, and more than 20
other states are contemplating labeling.
The U.S is pressing for the restrictions on importing genetically modified food to be eased. Some
in the U.S. see the European resistance as just another form of protectionism that promotes
domestic products over imported ones.
GM foods are not the only seemingly intractable issue standing in the way of a comprehensive
free trade agreement to remove most tariffs and other trade barriers, aiming to boost jobs and
growth. Genetically modified foods are part of a broader set of restrictions on both sides related
to agriculture and food safety. There are also significant differences on intellectual property and
financial regulations, among other thorny issues.
GMO and nutrition
More than 50% of the foods found in US supermarkets contain genetically modified ingredients.
Pro GMO - Defenders believe that cultivating genetically modified plants is good for the
environment and that it is perfectly safe. They also think that genetic engineering - which can
induce plants to grow in unfertile soils or to produce more nutrient foods - will soon become an
essential tool to fight hunger in a world increasingly populated.
Against GMOs - Skeptics concern that GMOs would be dangerous for the environment and
human health, and the risks that would arise are simply unacceptable. By this view, many
European countries are imposing restrictions on the cultivation and import of products and call
for labeling. All GMOs violate the natural barrier that separates different species, as host genes
coming from different species, and produce proteins foreign to the guest organism.
The potential offered by genetic engineering in the field of nutrition are countless: from the fruits
that do not rot, to cereals rich in iron and vitamins; from low-protein diets from rice to the beet
rich in fructans.
Since 1994, when it appeared the first modified tomato, to date, more than 1300 genes tested
have generated at least 300 distinct phenotypes in species such as corn, canola, soybean, potato,
tomato, cotton, tobacco, sugar beet, rice, wheat, peanut, birch, watermelon, grapes, barley,
eggplant and many others.
In most cases, the genetic modifications introduced and now widespread concern only two
characters: herbicide resistance (72 percent) and toxicity to the insect larvae (27.8 percent).
First GM Crop: FlavrSavr Tomato
Flavr Savr, a genetically modified tomato, was the first commercially grown genetically
engineered food to be granted a license for human consumption. It was produced by the
Californian company Calgene, and submitted to the U.S. Food and Drug Administration (FDA) in
1992.
Through genetic engineering, Calgene hoped to slow the ripening process of the tomato and thus
prevent it from softening, while still allowing the tomato to retain its natural colour and flavour.
The tomato was made more resistant to rotting by adding an antisense gene which interferes
with the production of the enzyme polygalacturonase. The enzyme normally degrades pectin in
the cell walls and results in the softening of fruit which makes them more susceptible to being
damaged by fungal infections.
Unmodified tomatoes are picked before fully ripened and are then artificially ripened using
ethylene gas which acts as a plant hormone. Picking the fruit while unripe allows for easier
handling and extended shelf-life. Flavr Savr tomatoes, on the other hand, could be allowed to
ripen on the vine, without compromising their shelf-life. The intended effect of slowing down the
softening of Flavr Savr tomatoes would allow the vine-ripe fruits to be harvested like green
tomatoes without greater damage to the tomato itself. The Flavr Savr turned out to disappoint
researchers in that respect, as the antisensed PG gene had a positive effect on shelf life, but not
on the fruit's firmness, so the tomatoes still had to be harvested like any other unmodified vineripe tomatoes. An improved flavor, later achieved through traditional breeding of Flavr Savr and
better tasting varieties, would also contribute to selling Flavr Savr at a premium price at the
supermarket.
The FDA stated that special labeling for these modified tomatoes was not necessary because they
have the essential characteristics of non-modified tomatoes. Specifically, there was no evidence
for health risks, and the nutritional content was unchanged
GOLDEN RICE
Golden rice is a variety of Oryza sativa produced through genetic engineering to biosynthesize
beta-carotene, a precursor of vitamin A, in the edible parts of rice. The creation of plants that
make or accumulate micronutrients is called Biofortification. The main purpose is to provide provitamin A to the developing countries, where malnutrition and vitamin A deficiency are common.
Why rice?
rice is the basic staple crop
cultivated for over 10,000 years
provides as much as 80% or more of the daily caloric intake of 3 billion people, which is
half the world’s population
The Golden Rice Project Started in 1982 by Ingo Potrykus-Professor emeritus of the Institute for
Plant Sciences and Peter Beyer-Professor of Centre for Applied Biosciences, University of
Freiburg, Germany. The Rockefeller Foundation, the Swiss Federal Institute of Technology, and
Syngenta, a crop protection company, funded the project.
Symptoms of vitamin A deficiency (VAD) include: night blindness, increased susceptibility to
infection and cancer, anemia (lack of red blood cells or hemoglobin), deterioration of the eye
tissue, and cardiovascular disease.
Nearly 9 million children die from malnutrition each year. A large proportion of those children
die from common illnesses that could have been avoided through adequate nutrition.
The reduced immune competence increases the morbidity and mortality rates of children.
VAD detrimental effects
•
•
coronary heart disease.
certain cancers (e.g., cancer of the lungs, prostate, etc.)
•
•
•
various childhood diseases which result in death (e.g., due to a weakened immune system).
childhood blindness (estimated to afflict 350,000 - 500,000 children per year).
macular degeneration, a leading cause of blindness in older people.
Mutate rice plants to produce carotenoids, or organic pigments, specifically β-carotene (provitamin A) in the endosperm, the edible part of the grain.
Golden Rice should be accessible locally, free of charge to farmers, who are able to grow, save,
consume, replant locally and sell Golden Rice.
Technically, the addition of 2 genes in the rice genome complete the biosynthetic pathway:
1. Phytoene synthase (psy) – derived from daffodils
2. Lycopene cyclase (crt1) – from soil bacteria Erwinia uredovora
These enzymes are involved in the biosynthesis of carotenoids (β-carotene) in the endosperm.
The presence of pro-vitamin A gives rice grains a yellowish-orange color, thus, the name ‘Golden.
Controversy against Golden Rice
Health
◦ May cause allergies or fail to perform desired effect
◦ Supply does not provide a substantial quantity as the recommended daily intake
Environment
◦ Loss of Biodiversity. May become a gregarious weed and endanger the existence of natural
rice plants
◦ Genetic contamination of natural, global staple foods
Culture
◦ Some people prefer to cultivate and eat only white rice based on traditional values and
spiritual beliefs
Other GMO Crops
POTATO: Potato is an excellent source of carbohydrates, feeds much of the world's population
due to its high starch content. To enrich the content, some researchers have transformed potato
tubers, obtaining samples with 60% starch more. But in the engineered tubers is increased
tendency to bruising.
CORN: The best known is the food transgenic Bt maize, much more productive than the "natural
brother", thanks to the ability to kill the larvae of moths and herbicides resistant.
SOY: GM soy is enriched with unsaturated fatty acids useful against many cardiovascular
diseases. Fairly widespread and contested is “rr” soy, which is resistant to herbicides. The
controversies arise from the fact that because of this additional property will have the increased
use of herbicides and the risk that residues of these "poisons" remain on the plant and to come
up in the consumer's plate.
SALMON: The salmon was modified to develop a rapid growth and resistance to cold.
In conclusion, GM crops available on the international market today have been designed using
one of three basic traits: resistance to insect damage; resistance to viral infections; and tolerance
towards certain herbicides. GM crops with higher nutrient content (e.g. soybeans increased oleic
acid) have been also studied recently.
SOME QUESTIONS ABOUT GENETICALLY MODIFIED FOODS
Are people’s reactions related to the different attitudes to food in various regions of the world?
Depending on the region of the world, people often have different attitudes to food. In addition
to nutritional value, food often has societal and historical connotations, and in some instances
may have religious importance. Technological modification of food and food production may
evoke a negative response among consumers, especially in the absence of sound risk
communication on risk assessment efforts and cost/benefit evaluations.
Are there implications for the rights of farmers to own their crops?
Yes, intellectual property rights are likely to be an element in the debate on GM foods, with an
impact on the rights of farmers. In the FAO/WHO expert consultation in 2003
(http://www.who.int/entity/foodsafety/biotech/meetings/en/gmanimal_reportnov03_en .pdf),
WHO and FAO have considered potential problems of the technological divide and the
unbalanced distribution of benefits and risks between developed and developing countries and
the problem often becomes even more acute through the existence of intellectual property
rights and patenting that places an advantage on the strongholds of scientific and technological
expertise. Such considerations are likely to also affect the debate on GM foods.
Why are certain groups concerned about the growing influence of the chemical industry on
agriculture?
Certain groups are concerned about what they consider an undesirable level of control of seed
markets, by a few chemical companies. Sustainable agriculture and biodiversity benefit most
from the use of a rich variety of crops, both in terms of good crop protection practices as well as
from the perspective of society at large and the values attached to food. These groups fear that
as a result of the interest of the chemical industry in seed markets, the range of varieties used
by farmers may be reduced mainly to GM crops. This would impact on the food basket of a
society as well as in the long run on crop protection (for example, with the development of
resistance against insect pests and tolerance of certain herbicides). The exclusive use of
herbicide-tolerant GM crops would also make the farmer dependent on these chemicals. These
groups fear a dominant position of the chemical industry in agricultural development, a trend
which they do not consider to be sustainable.
. What further developments can be expected in the area of GMOs?
Future GM organisms are likely to include plants with improved resistance against plant disease
or drought, crops with increased nutrient levels, fish species with enhanced growth
characteristics. For non-food use, they may include plants or animals producing pharmaceutically
important proteins such as new vaccines.
What has WHO been doing to improve the evaluation of GM foods?
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WHO has been taking an active role in relation to GM foods, primarily for two reasons:
on the grounds that public health could benefit from the potential of biotechnology, for example,
from an increase in the nutrient content of foods, decreased allergenicity and more efficient
and/or sustainable food production; and
based on the need to examine the potential negative effects on human health of the
consumption of food produced through genetic modification in order to protect public health.
Modern technologies should be thoroughly evaluated if they are to constitute a true
improvement in the way food is produced.
WHO, together with FAO, has convened several expert consultations on the evaluation of GM
foods and provided technical advice for the Codex Alimentarius Commission which was fed into
the Codex Guidelines on safety assessment of GM foods. WHO will keep paying due attention to
the safety of GM foods from the view of public health protection, in close collaboration with FAO
and other international bodies.