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Genetically Modified Organism

GloFish photograph showing several fish, transgenic zebrafish in an aquarium. Fish yellow, red and green are visible, while the zebrafish wearing blue and white horizontal stripes
GloFish one of the first genetically modified animals sold as pets.

A genetically modified organism (GMO) is an organism whose genetic heritage has been altered by humans. Depending on the laws, the means these changes range from selection methods of genetic engineering. These latter methods can modify organisms by transgenesis is to say, the insertion into the genome of one or several new genes. A "transgenic organism," a term that refers to organisms that contain genes in their genome "foreigners" is always a genetically modified organism, the reverse is not always true.

The implementation of transgenesis allows the transfer of heritable genes ). The innovative aspect of these new techniques and their potential applications, including medical and agricultural sectors, have started to consider ethical . Within biotechnology , GMOs are an area of research done since the 1990's the subject of considerable investment in research and development funding from both public and private.

While some GMOs may pose risks, especially vis--vis the health (production of molecules unwanted) or the environment (unwanted spread of genes ), some scientific organizations, including the International Council for Science , argue that GMOs are not marketed dangerous for human health, and that risks are properly controlled release. Others, such as the Research Committee and Independent Information on Genetic Engineering (CRIIGEN) , in France , or the Independent Science Panel , the UK , believe that the studies accreditation bodies references are insufficient, and that in the area of field crops precautions fail to prevent genetic pollution of the environment. They are supported in that by supporters of anti-GMO.

Nonexistent in 1993, cultivated GMOs (soya, maize, cotton, etc..) are continuously expanding and in 2009 are around 134 million hectares, " , or more than 9% of the billion and a half hectares farmland.

In May 2010, the journal Science reports the completion of the first organism whose entire genome has been synthesized by scientists. It is not a "creation" as such but to the artificial production of existing genome , .

Summary

"A genetically modified organism (GMO) is an organism (animal, plant, bacteria) which was modified genetic material (gene array) by a new technique called" genetic engineering "to give it a new feature. "
The OECD
glossary of the OECD
"Plant or animal micro-organism or virus, Which Has Been Genetically engineered or modified"
Flag: United States United States
FDA
Authority to monitor feed and medicine 		For this central U.S. the term GMO is not used but they use the term Genetically engineered, according to the FDA and USDA :

"What is a genetically engineered food?
A genetically engineered food is produced from seed whose genetic makeup has been altered by a technique called recombinant DNA or gene splicing, to give the plant a desired character. Foods derived from genetic engineering are also called genetically modified , although may also apply to foods derived from plants modified by other culture methods (intersection according to James Maryanski, biotechnology coordinator at the Food FDA. "Farmers and scientists genetically modify plants for centuries, "he said (...)

Flag: United States United States
Department of Agriculture USDA 		"Genetic modification: the production of hereditary improvement of plants or animals for a specific purpose both by genetic engineering techniques by more traditional methods of improvement. Some other countries that the U.S. uses this term only for what is genetically engineered.

GMO organism produced by genetic modification. "

Flag: Canada Canada
Agency Canadian Food Inspection 		"Genetic modification (GM): Changes in the genetic material of an organism, whether through conventional breeding, genetic engineering, mutagenesis, etc.. A GMO is a genetically modified organism. For some, however, the use of the term GMO is smaller and involves only organisms modified by genetic engineering techniques.

Selected classical method used to select certain traits in the progeny of plants or animals (also known as selective breeding). The use of selective breeding to produce varieties of plants and breeds of animals. Genetic engineering (GE): A method by which the genetic material of an organism is changed in a way that does not occur naturally by mating and / or natural recombination. For example, a method used to transfer (or remove) a direct gene from one organism to another (also known as recombinant DNA technology

"A" GMO "is an organism (plant, animal or micro-organism) whose genome has been deliberately altered by man through a technique: transgenesis, involving in vitro culture and genetic engineering. "
ISAAA
Educational publication for journalists, page 25 		"A genetically modified organism (GMO) is an organization in which one or two (rarely more) genes of an organism whose appearance is close or distant have been introduced to give it a new feature. In the case of plants, a genetically modified plant contains one or more genes that were inserted through biotechnology, rather than being acquired through pollination and selective breeding of plants. The sequence of the inserted gene (ie d. Transgene) may come from the same species or a species completely different. "

Different GM

In theory, every living organism can be genetically engineered, it is still necessary that the tools are available for each species, or that it has a scientific or commercial interest. The vast majority of GMOs are created for purely scientific. The modification of the genome of an organism is now one of the most used tools for understanding the functioning of an organism , , .

Many micro-organisms ( bacteria , algae , yeasts ) are relatively easy to change and grow, and are a relatively economical to produce specific proteins referred to medical insulin, growth hormone, etc.. Tests are also conducted for the same purpose from mammals, to produce the desired protein in milk, easy to collect and process . The proteins thus obtained recombinant say are not themselves GMO.

The major crops (soybean, corn, cotton, tobacco, etc..) Have genetically engineered versions, with new agricultural properties: resistance to insects, resistance to a herbicide, nutrient enrichment components . However, in the context of food, these claims are controversial .

The main GM crops grown in 2006 are soybeans, used to feed livestock, and corn.

The transgenic animals are more difficult to obtain, and the resulting varieties are not yet marketed for consumption .

If a line of men came from genetic modification, it would be part of GMOs .

Comparison with other gene exchanges

Exchange of genes without human intervention

The name of genetically modified organism refers to an artificial modification of the genetic heritage of an organism. But spontaneous mutations as well as systems for natural transfer of DNA called horizontal transfer of genes exist that lead to the appearance of organisms whose genetic material is unpublished. Thus, for example, tobacco (Nicotiana tabacum) and wheat resulting from the addition of spontaneous ancestral genomes . Discovered in the late 1950s , , the a href = "% C3% Transfert_horizontal_de_g a8ne"> horizontal gene transfer has since been recognized as a major process of evolution of bacteria but also eukaryotic . The emergence of new genes in a species is an important part of the process of evolution.

The main features of the natural exchange of genes, some of which are operated by the techniques of genetic engineering are as follows:

  • The retroviruses are viruses able to integrate their genetic information in the genome of their host. Through sequences present on both sides of the viral DNA, which are recognized by the host genome, it accepts its hyphenation , and integration of viral DNA. The consequences for the host are rarely positive, they consist mainly of disease, cancer, scabies, and even sudden death.
  • The plasmid , which is a small circular DNA molecule is mobile and can move from one cell to another. Some plasmids can then integrate into the genome of the host cell. This form of DNA transfer is observed for bacteria , including genes for resistance to antibiotics. The integration of bacterial plasmid into the genome of a domain different ( eukaryotic or archaeal ) is limited to specific bacteria, and for pairs of species identified. Thus, Agrobacterium tumefaciens is a bacterium which a fragment of the plasmid (T-DNA) is able to enter into a plant cell and integrate into its genome.

We also include other types of events that do not participate in exchanges of genetic material, but which remain important in the context.

  • The reproduction interbreeding between individuals allows the diffusion of genetic material. The product may be a hybrid with specific genetic characteristics. In addition, the reproduction may be an opportunity for viruses and other exchange factors of genes to move from one partner to another.
  • The mutations are not in themselves a means of exchange, but they can produce new genetic material to be broadcast later by exchange, thus contributing to the evolution of species. Many mutations are neutral, some are supportive, but others are associated with genetic diseases or cancers.

Exchange of genes carried by humans before GMOs

The Man in the trade of genes in plants and animals since the invention of agriculture, through selection and hybridization.

Selection

The plants grown man now, and animals including humans farming practice, did not exist 10,000 years. They are the result of a process of domestication introduced to the beginnings of agriculture , about the year -8000. Consciously or not, humans have selected - by choosing to eat and grow plants with higher yields (larger seeds, smaller seeds, less bitter taste ...) - some individuals within populations of plants . Indeed, genetic mutations occur spontaneously and continuously generate living individuals. Thus, the maize grown is the result of introgression of 5 mutations in teosinte (wild maize), which transformed the morphology of the plant especially at the branching of the plant and the attachment of corn kernels roundup , .

Hybridization
Main article: Hybrid.

Hybridization is the crossing of two individuals in two varieties, sub-species (interspecific crossing), species (interspecific crossing) or genera (intergeneric crosses) different. The hybrid is a blend of features DNA from both parents. The hybridization can be caused by man, but it can also occur naturally . It is used, for example, to create new varieties of apples , by crossing two existing varieties with interesting features .

Selection and hybridization are that the vast majority of plants now grown around the world are the result of a considerable number of the successive genetic mutations that made not only more productive but also better suited to different uses at different conditions farms and their land.

History

From genetics to genetic engineering

Related Articles: Genetics , DNA and genetic engineering.

In the early twentieth century, the rediscovery of the work of Gregor Mendel (1822-1888) and the work of Thomas Morgan (1866-1945) on the fly Drosophila melanogaster to understand that heredity is due to transmission of particles called genes arranged linearly on chromosomes. In 1941, two U.S. geneticists (George Beadle and Edward Tatum) have shown that a gene encodes a protein given. In 1953, the work of James Watson , Francis Crick , Maurice Wilkins and Rosalind Franklin , highlight the double-helix molecular structure of DNA. This discovery opens the way for a new discipline of molecular biology in 1965 , the discovery of restriction enzymes , proteins capable of cutting the DNA at specific sites, giving researchers the tools they needed to establish a mapping of the genome. It also opens the way for development of genetic engineering by enabling the "manipulation" in vitro to specific portions of DNA and genes so. This is the technology of recombinant DNA , which allows the insertion of a portion of DNA (a gene or genes) in another DNA . This finding was confirmed in 1973 by Paul Berg and colleagues.

Getting Started

The first GMOs are genetically modified bacteria. The first attempt to transgenesis by American Paul Berg and colleagues in 1972 , consisted of the integration of a fragment of DNA virus SV40 , a carcinogen , into the genome of the bacterium E. Coli present naturally in the human gastrointestinal tract , . This trial aimed to demonstrate the ability to recombine in vitro, two DNA of different origins. The recombinant DNA could be replicated in bacteria . However, before the power tools at their disposal, the concerned scientists decide at the Asilomar conference of a moratorium to be lifted in 1977.

In 1977, the Ti plasmid of the soil bacterium Agrobacterium tumefaciens is identified. This plasmid is used to this bacterium as a vector to transfer a DNA fragment, the T-DNA (transfer DNA or transferred DNA) in the genome of a plant. This DNA contains several genes whose product is required for the bacterium during its infection cycle. A few years later this bacterium will be used to create the first transgenic plants , .

In 1978, a strain of yeast (eukaryote) auxotrophic for leucine is transformed with a bacterial plasmid carrying the LEU2 gene.

In 1978, a gene encoding human insulin is introduced into the bacterium Escherichia coli , so that it produces the insulin human. This so-called recombinant insulin is the first commercial application in 1982 of genetic engineering . Insulin currently used to treat diabetes is produced from GMOs .

In 1982, the first genetically modified animal is achieved. It's a mouse in which the giant gene of rat growth hormone was transferred . In 1983 , the first genetically modified plant is obtained: a tobacco plant modified to resist the antibiotic kanamycin . 1985 sees the first transgenic plant resistant to an insect : a tobacco gene in which a toxin of bacterium Bacillus thuringiensis has been introduced.

In 2010, the first organism containing a full genome produced by humans is described in the journal Science. It is a strain of Mycoplasma capricolum , whose genome has been removed is replaced by the genome "JCVI-syn1.0" designed by the team of Craig Venter , giving rise to a strain Mycoplasma mycoides. The genome was created by the synthesis of 1078 oligonucleotides of 1 080 base pairs is 1078 fragments were assembled into 109 fragments of 10 080 base pairs, assembled themselves into 11 fragments of 100 000 pairs bases finally meeting in the circular genome of 1,077,947 base pairs. ,

Evolution of Law

Related Articles: Patenting Life and regulation of GMOs.

Louis Pasteur was granted in 1873 the first patent for a living organism, a strain of yeast used in the manufacture of beer.

In 1977 and 1978 , the United States , sixteen bills designed to regulate practices related to scientific research in molecular biology have been introduced in Congress. None succeeded .

In 1980 , the Supreme Court of the United States admits for the first time ever the principle of patenting of life for a bacterium genetically modified. This is a new oil-eating bacteria known as bacteria developed by Dr. Chakrabarty. This legal decision is upheld in 1987 by the U.S. Patent Office, which recognizes the patentability of living , with the notable exception of humans.

In 1986 , then what made its territory on the first field trial of transgenic plant (a tobacco resistant to an antibiotic ), the France set up the Biomolecular Engineering Commission (CGB), National Commission, which depends on the Ministry of Agriculture. She is responsible for compliance with regulations, control field tests and issues licenses for testing and marketing of GMOs.

In 1989 , establishment of the Commission on Genetic Engineering (CGG). The GSA depends on the Ministry of Research. She is responsible for assessing the risks associated with obtaining and use of GMOs and to propose measures for containment desirable to prevent these risks.

In 1990 , the European Commission takes the issue of GMOs. She said: "The use of modified foods should be introduced to limit the negative effects it can have on us." She asked that the precautionary principle , which involves extensive research on product safety, is respected .

In 1992 , the European Union in turn, acknowledges the patenting of life and gives a patent for creating a transgenic mouse. It adopts in 1998 the Directive on the patentability of biotechnological inventions : inventions are now on plants and animals and gene sequences.

The principle of substantial equivalence appears for the first time in 1993 in a report The OECD .

In 1998 , Europe adopted a Directive on the fundamental protection of biotechnological inventions are now patentable inventions of plants and animals and gene sequences.

If the first marketing approvals have resulted in the establishment of bodies responsible for assessing the risks of GMOs, Susan Wright wrote in 1994 : "When genetic engineering was seen as an investment opportunity, it has produced an adaptation of standards and standard scientific practices at companies. The awakening of gene coincides with the emergence of a new ethics radically defined by trade "

In twenty years, in parallel with the emerging science of biotechnology and economic issues, a branch of law and regulations were created. The two most important patents are those of health and agriculture. The potential market is in the hundreds of billions of dollars . Ethical goals, economic and political GMOs are now a global issue .

Progressive Marketing

1982 saw the first commercial application of genetic engineering: the production of insulin to treat diabetes . The insulin protein is now used by millions of diabetics worldwide .

In 1990 , the first food product of genetic engineering is marketed in the United States and Canada , it is chymosin , enzyme digestion specific for the casein and used in the food industry as substitute the rennet to curdle milk.

In 1993 , the recombinant bovine growth hormone (rbGH or rBST) is authorized for marketing in the United States by the Food and Drug Administration. Designed to make the most productive dairy cows, the hormone that may be present in many countries is banned in the European Union and Canada . In August 2008 , the company Monsanto , the only company to market the rbST under the brand name Posilac announces its withdrawal from the manufacture .

Produced by micro-organisms genetically modified, the insulin , the chymosin or bovine growth hormone, known as "recombinant" are not themselves of GMOs , .

1994 : The first genetically modified plant is sold: the tomato Flavr Savr , designed to stay firm longer once picked, it is no longer sold since 1996 as it was, according to some, considered bland and too expensive by consumers . However, the case of the Flavr Savr was in 1998 integrated in a lawsuit with the U.S. Agency for Food and Medicine by an advocacy group for consumers, which resulted in a conviction of this organism .

Since then, dozens of genetically modified crops were commercialized in the world and, according to the WHO consumption had no effect on human health .

1 995 - 1996 : Marketing the United States by the company Monsanto 's soya Roundup Ready, resistant to herbicide nonselective Roundup , maize "yield gard", resistant to stem borer of maize and of cotton 'Bollgard' is permitted . The organization Greenpeace launched an international campaign against the commercialization of GMOs in the field of nutrition and against their spread in the environment .

January 29, 2000 , is signed the Cartagena Protocol on Biosafety to the Convention on Biological Diversity, more commonly called the Cartagena Protocol on Biosafety. Under the aegis of the UN , it is the first international environmental agreement on GMOs. Identifying their characteristics, it is a legal instrument based on the principles of precaution and prevention that States may oppose to the rules of the WTO . Entered into force September 11 2003 , it has so far received 157 instruments of ratification

In 2000, The European Union sets the threshold to 0.9% of GMOs as a food product may contain European without being obliged to report on the label .

In 2001 : On the occasion of the first World Social Forum in Porto Alegre , Via Campesina launched an international appeal to the union to fight against GMOs and seeds for farmers. At the close of the forum, as Attac, 184 environmental organizations committed to supporting the struggle of La Via Campesina worldwide and to organize actions to stop the importation and use of GMOs

Although the GM maize cultivation is authorized in France until 21 March 2000 , producers have decided not to plant to meet their choice of clients and consumers. The European judges in Luxembourg conclude that France is obliged to allow the cultivation of GMOs within its territory unless it can provide information proving that the food poses a risk to human health or the environment. They extend the authorization period to 10 years of cultivation, while the initial order and limited to 3 years. The State Council bows to EU law. On 14 December, Montpellier , Greenpeace and several hundred people, with Jos Bov , protesting against GMOs at the conference of the UN dedicated to them . On May 13, 2003, the U.S. government filed a complaint with the World Trade Organization to force the EU to lift its "de facto moratorium" on the sale of seeds and genetically modified foods .

The World Trade Organization allows the restriction of imports in the case of a "protection against risks to food safety and the risks of invasive species from plants genetically modified" , but these conditions are not met, according to the WTO, the dispute between the producing countries (USA, Canada, Argentina) to the EU . The European community has pledged to respect the rules of the WTO on GMOs, by February 2008 .

Development of transgenic organisms

Related article: Transgenic (biology).

Except for the xenobiology , the possibility of producing a GMO is based on the fact that the genetic language is universal throughout the living world known so far. Because of this universality, a gene , from a body donor ", can be introduced into an organism" recipient ", which takes its own account, is able to decode and produce the well (s) protein (s) that corresponds to each of them having a function. This linearity based on an interpretation of the central dogma of molecular biology is actually more complex:

  • one gene can encode multiple proteins
  • protein may have several functions
  • the expression of a gene depends on various environmental factors.
  • the universality of the genetic code , does not guarantee that the expression of a gene from one organism be carried out properly or be carried into another organism. A number of information contained in genes are not (or poorly) included one species to another. A series of modifications of the gene is then necessary. The transgene introduced ultimately is not the original gene, but a modified gene, an artificial genetic construction.
  • even if the gene inserted into the new organization is effectively translated into the protein it is supposed to express, it is not in the state of knowledge empirically and systematically assess the transgenesis did not alter the quality of the protein in question. Genetic diseases in the prion are due to simple defects in protein folding of a particular .

After transgenesis, the protein may be subject to post-translational modifications necessary for its functionality. The cellular environment varies from one organism to another, it is not in the state of knowledge to determine the identity assumed to exist between the place of original expression of the protein (in the body "donor" ) and place the final expression (in the body "recipient").

Different stages of development of transgenic organisms

The various steps of creating a GMO are:

  • Identification and cloning of the sequence of interest to introduce into the target organism,
  • The realization of the transgene, that is to say, the DNA molecule to be introduced into the target organism, it may be the sequence of interest only, or sequences containing multiple genes.
  • The introduction of the transgene in a cell of the target organism and its integration into the genome.
  • In some cases a step of regenerating a complete organism is necessary (eg you can modify a plant cell from which a plant grows)

The latter comprises two basic steps, different from each other, but often confused. The transfer of a molecule of DNA in an organism and the transfer of the same molecule in the genome of the organism. This confusion is reinforced by the use of the term vector which refers to both a DNA molecule containing the gene of interest ( plasmids , transposons , viruses (genome)), or living organism ( Agrobacterium tumefaciens , virus) that allows the introduction of the first vector in the target organism.

Techniques of gene transfer in prokaryotes, bacteria and archaea

Transformation without integration into chromosomal DNA

The plasmids bacteria have the advantage of being easy to purify and change to incorporate new genes. The transformed plasmid is incorporated into the bacteria where it remains distinct from the chromosomal DNA (except in the case of episomes ), while being able to express one or more gene (s) of interest. The modified plasmid usually has a gene for resistance to an antibiotic that is used as a marker of transformation (or selection). Thus, only bacteria that have incorporated the plasmid are capable of growing in a medium containing the corresponding antibiotic.

With large capacities multiplication of bacteria ( Escherichia coli doubles its population every 20 minutes), it is possible by this technique have the genetic sequence of interest in large quantities.

However, the specificity of plasmid systems limit bacteria capable of incorporating the modified plasmid. On the other hand, the stability of the transformation plasmid is dependent on the need of the cell to maintain this plasmid, that is to say the bacterium retains the plasmid acquired if it confers a selective advantage, usually it is the resistance to an antibiotic. If these bacteria are cultured in the absence of the antibiotic, they will tend not to retain the plasmid, then said he must exert selection pressure for bacteria to maintain it.

Some archaea can also be transformed with a plasmid, but the methods of molecular biology associated with these organisms are still poorly developed.

Transformation with integration into the chromosomal DNA

The episomes are plasmids with certain genes for further synthesis of restriction enzymes that lead to its integration into chromosomes by bacterial recombinant episomal.

Once integrated into the chromosome of the cell, or the transmission of genetic traits is ensured during the mitosis of stem cells into daughter cells, unlike the plasmids are distributed randomly.

Another way to make a transformation of bacteria with DNA integration, is to use transposons. In some bacteria, these active transposons can carry and to integrate the gene of interest.

Some viruses are also capable of infecting bacteria and archaea, and integrate some of their genome into the genome of their host.

Technology transfer of genetic material in eukaryotes (plants, animals, fungi, etc.).

Production scheme of a GMO

Genetic Vectors

Like bacteria, it is necessary to use genetic vectors to introduce DNA sequences of interest into the genome of the organism to modify. Many types of vectors exist after the body targets, for example:

  • Plasmids : They are also plasmids can be introduced into eukaryotic organisms. These can either be maintained in the cell or integrated (at least in part) to the genome of the target organism.
  • Transposons : transposable DNA sequence that is used with a transgene which were added to the ends of the recognition sites of DNA. The size of the transgene must be limited. The transposon-based techniques are used primarily on Drosophila.

span class = "mw-headline" id = "Transfert_du_matriel_gntique_dans_l_organisme_cible"> Transfer of genetic material in the target organism

Transfer indirect transfer of DNA or biological

The DNA sequences of interest ( DNA ), foreign to the body, can be introduced into the body of destination through another living organism:

The main techniques used are the following:

  • Agrobacterium tumefaciens : This bacterium has a plasmid (called Ti plasmid ) and a portion of DNA (the T-DNA for DNA Transferable) can integrate into the genome of plants, making it the most widely vector used to create transgenic plants. The transgene is integrated into the plasmid of this bacterium, which the vehicle until the chromosomal DNA of the host. Several methods exist for transforming a plant with Agrobacterium tumefaciens:
  1. The bacteria can be infiltrated into the leaves, or penetrate to the level of injury.
  2. The "soaking" of flowers in a solution of Agrobacterium tumefaciens. This method has the advantage of integrating the transgene in the germ cells (pollen and ovules) and thus to obtain transgenic offspring.
  3. The transformation of plant cell undifferentiated (callus) by Agrobacterium tumefaciens. It must then regenerate plants from these calli.
  • Retrovirus : these viruses with the ability to integrate their genetic material into host cells to develop infection, vectors have been developed by replacing the gene allowing infection by a transgene. However, retroviruses are very specific to their host, and these vectors can accept transgene too large.
Direct transfer of DNA
Photograph showing a gun DNA
Gun DNA

Bodies whose membranes are weakened or plant cells devoid of walls (such as protoplasts) are brought into contact with DNA. Then a physical or chemical treatment allows the introduction of DNA into cells. Other techniques such as micro-injection, macro-injection and other techniques biolistic allow the mechanical introduction of DNA into cells.

Crossing and cell fusion
Main article: Cell Fusion.

The oldest methods of transferring genetic material used by man is a cross between individuals. This can be achieved between individuals of the same species or closely related species ( hybrid ).

One or two individuals may be transgenic individuals, this is particularly used to combine several traits changed in a single individual.

The cell fusion (including fusion of protoplasts ) which results in living cells with new combinations of heritable genetic material are formed through the merger of two or more cells using methods that are not implemented in a natural way.

Integration of genetic material into the genome of the modified organism

The genetic material transferred to the modified organism, can be contained in a plasmid to be retained as is, in this case there will be no integration into the genome in the proper sense. In other cases, the transgene is integrated by recombination into the genome of the organism.

Genes used

The list of genes that may be used is virtually infinite, but it is possible to define different categories of genes.

Marker Genes

Main article: gene marker.

This is not characteristic that is desired to give to the organization, but fireworks technique for identifying and sorting cells in which the desired gene construct was introduced, those where the operation failed.

The antibiotic resistance genes used as markers for selection simple and practical: it is sufficient to transplant cells in a medium containing the antibiotic, to keep the cells in which the operation was successful. Genes for resistance to antibiotics (which can still be found in some current PGM) were those for resistance to kanamycin / neomycin, streptomycin and ampicillin. Their choice was a natural, in that they were commonly used to ensure the purity of microbial cultures, medical research and biology, and little or no use in medicine man. Since 2005, they are prohibited for any new GMO.

Never to leave in place the gene of interest , so be sure that resistance genes do not interfere with the phenotype observed, two methods are possible:

  • a method of excision of these cassettes "resistance genes"
  • transgenesis with a binary (two plasmids: one carrying the cassette "gene of interest", the other tape "marker gene". In the offspring of the GM plants obtained, only those with the cassette "gene interest "are deducted.

Resistance Genes

Main article: resistance gene.

For insects

Related article: Bt Corn.

This resistance is conferred to plants by genes encoding a truncated form of protein endotoxins , produced by certain strains of Bacillus thuringiensis (bacteria that live in soil). There are many toxins , active on different types of insects : for example, some plants resistant to lepidopteran insects , such as the European corn borer (Ostrinia nubilalis), carry genes Cry1-type (A).

Herbicide

Examples of genes conferring tolerance to glufosinate ammonium (in the Basta, Rely, Finale, Challenge, Liberty and bilanafos) and glyphosate (as Roundup ).

Gene sterility

Gene male sterility

Main article: male sterility.

The male sterility gene (barnase) encoding a ribonuclease which precludes the expression of molecules of ribonucleic acid necessary for fertility. It is controlled so as not to be expressed only in the pollen grain.

The barstar gene, meanwhile, is an inhibitor of the ribonuclease, and makes its pollen fertility.

The combination of the two genes can, for example, to prevent inbreeding in a variety of pure carrier barnase, but to allow seed production by a hybrid of this variety and another carrier barstar. Thus, one can obtain homogeneous hybrid seeds (used for salads in Europe), or prevent the reuse of seeds.

Technology "Terminator"

It's actually a "technology protection system", patented by the company Delta & Pine Land and the U.S. Department of Agriculture. This technology allows genetic modification of seeds to prevent germination of the next generation of seeds. It's not about sterility in the strict sense since plants can produce seeds, germination is of the latter is inhibited. This technology has been dubbed Terminator by its opponents gene antisense or sense blocking the translation of other genes

The operation involves introducing an extra copy of a given gene, but in reverse orientation (referred to as gene "antisense"), or sometimes in the same direction, but truncated. The presence of this gene "wrong" leads to the phenomenon of RNA interference and reduces drastically the amount of RNA corresponding, decreasing the synthesis of the enzyme encoded by this gene. One such example is the potato , which synthetases are produced in limited quantities, so as to produce a different starch.

reporter genes

Main article: reporter gene.

In basic research the genes can be modified to study the expression profile and / or location of the associated protein. Why the gene of interest is fused to a reporter gene (gene encoding a fluorescent protein such as GFP or an enzyme whose action can be viewed as the beta-glucuronidase ).

Production of proteins

In some cases the goal of a GM will be producing large quantities of a protein of interest, also known as recombinant protein in this case. The most famous being the insulin , the growth hormone or the factor VIII. In this case a single cell (bacteria, yeast, cell Chinese hamster ovary (en) ) or an entire organism (tobacco), has received a transgene encoding the protein of interest. The isolated cells were first cultured in the bioreactor , and a cleansing of the protein of interest takes place. One method of purification is the most common use of the technique of chromatography , either affinity, ion exchange or sharing.

Major applications of GMOs

GMOs are used in the fields of research , the health of the agricultural production , and industry .

GMOs used in basic research

In basic research , obtaining GMOs is not necessarily a goal but often a way to find answers to some problems: how genes do they control the development of an embryo? What are the stages of cell division? What does each phase of development?

The inactivation of a gene is a method used in the laboratory to understand the role and function of this gene. In some instances this inactivation is by transgenesis by inserting a DNA fragment in place of the gene to be studied .

Study of developmental genes, and evolution

For example by transferring a gene from mice in the Drosophila , it was shown that in addition to sequence similarity there was a similarity of function between genes of two species. Thus the gene Hox -b9 mouse was transferred into a Drosophila embryo which has changed its organization plan showing a blank tab instead of antennas . We get the same result if we mutate the gene Antennapedia of Drosophila. So there is a similar function for these two genes they control embryonic development in both species. It is shown that the mechanisms of gene expression during embryonic development are the same in both species, which highlights the relationship and processes of species evolution.

Mapping and sequencing genomes

Main article: Draft genome sequencing.

The sequencing of the human genome and other species, such as Drosophila melanogaster or Arabidopsis thaliana , were conducted in a context of basic research with a goal to run applications medical.

The analysis of whole genomes requires the creation of "gene banks" , that is to say hardware devices in which DNA analysis is "stored" and available. The DNA of the species studied is cut and inserted into the genome of microorganisms (bacteria or viruses). Each of these microorganisms is a clone containing a specific part of DNA, which can handle at any time. This allows the identification of genes and their position on chromosomes. Finally this leads to the complete sequencing of the genome.

GMOs used in the medical field

What exists

The first genetically modified organisms have enabled the production of medical substances: insulin used to treat diabetes , growth hormone human used to treat certain forms of dwarfism, vaccine hepatitis B made from yeast and hamster ovary cells (CHO) .

Today, if the research effort still exists in these areas, a pole very attractive commercially grows with the production of nutraceuticals. Foods fortified with drug substances in the milk of mammals exist already .

Searching

GMOs represent a promising technology for medicine and the pharmaceutical industry because of their potential for breeding . The genetic engineering could, for example, help in the fight against certain diseases by implementing new processes for obtaining products such as therapeutic antibodies to treat cancer . Remove the genes for resistance to an antibiotic currently used in gene selection is a major challenge of current research.

food industry
: functional foods. They deal with different ways of producing molecules for therapeutic use. Among these means of production are:

One of the most promising in terms of profitability is applied to the transgenic dairy species, because the milk is easy to "harvest" in large quantities.

The first case of molecular animal was a sheep in GM developed to synthesize the milk of a-antitrypsin , a protein used to relieve the emphysema in the human. The transgene encoding this molecule has been isolated from the human , then introduced into the genome of the sheep .

The possibility of producing drugs in cells of insects appears to be an important route to Grard Devauchelle, of the Research Unit of Comparative Pathology at the INRA of Montpellier , which predicts that: "In the coming years is certainly this kind of method that will produce molecules for therapeutic use to replace those who today are extracted from bodies. " .

The use of a method over another is determined by its effectiveness in individual cases .

Xenograft
Main article: Xenotransplantation.

The idea of using animal organs for human transplants is old. The pig , which has the double advantage of being both physiologically quite similar to humans and have very few diseases transmitted to it, is regarded by experts as the best organ donor possible. Of pigs transgenic could provide organs "humanized". This therapeutic approach is of real interest but still requires extensive research, including the discovery of genes inhibit reactions of rejection .

Gene Therapy
Main article: Gene Therapy.
Main article: Transgenic animal.

Gene therapy involves transferring genetic material into cells of a patient to correct the absence or disability of one or more genes that cause disease. She is still in clinical research .

GM plants used in food processing

What exists

Transgenic crop traits tested (in%) over the period 1987-2000
In countries
industrialized 		countries
Least Developed
Herbicide tolerance 29 37
Insect resistance 19 29
Product Quality 16 6
Added genes 12 10
Virus resistance 8 10
Agronomic
(Yield, drought tolerance, etc.). 		5 1
Resistance to fungi / bacteria 5 3
Other 6 4

The main crops ( maize , rice , cotton , rapeseed , beet , potato , soybean , carnations , chicory , tobacco , flax , sunflower ) have genetically modified varieties. There are also tomatoes , strawberries , bananas , cabbage , cauliflower , etc..

The first genetically modified (GM) were the to be made tolerant to a herbicide. Today, the corn , the soybean , the cotton of canola , the sugar beet , flax are genetically modified to resist a herbicide molecule content in total, the glyphosate.

Another perspective has led to the development of plants secreting insecticide. The Bt maize , Bt cotton their name from Bacillus thuringiensis , a bacterium that produce insecticidal proteins, which gives these plants resistance to major insect pests to them, including the ECB in the case of corn or budworm in case of cotton.

Processed foods (oils, flours, etc..) From genetically modified raw materials are also commercially .

Current Research

A third way is to produce genetically modified crops to increase their nutritional value ( golden rice ) and their resilience to climate variations (drought, monsoons, etc..) , . Tell GM 2nd-generation, these cereals are still under development.

Research today is moving toward changing several lines in a single GM plant. For example, the Chinese government pilot project aimed at improving the nutritional quality of rice, but also its adaptation to stressful environments (drought, salinity, etc.).. This rice, called SUPER GREEN RICE, should also contain several genes for resistance to insects and diseases .

The deletion of genes for resistance to an antibiotic used in gene selection and the elimination of toxic substances produced naturally by some plants are set axes of ongoing research .

GM animals used in food processing

Current Research

In 2011, the journal Science reported the creation of genetically modified chickens to inhibit the activity of the polymerase of the virus from bird flu. This inhibition prevents the virus from passing phase of viral replication and therefore prevent its spread in poultry .

Use in industry

What exists

GMOs allow the production of raw materials for industry: GMO poplar trees with a rate of lignin has been less successful, facilitating the process of making paper pulp by reducing the use of chemicals needed to break the wood fiber. However, due to the limited application of Stationers, this production should shift to the production of bioethanol , .

Today, biotechnology using enzymes used to treat industrial wastewater .

In March 2010 , the European Commission has decided, since the Parliament could not reach a decision by the voice of the Commissioner for Health and Consumer Policy John Dalli , to allow the cultivation of the apple Earth transgenic Amflora. It is intended for the production of potato starch for the textile, adhesive or paper. Is referred to improved productivity through savings on the production of raw material, starch. Its license is validated by the Directive 2001/18/EC (known as "the dissemination of GMOs "). Its use by the food industry is not expected, but the presence of unwanted residues in the potato products for consumption (maximum 0.9%), the subject of complementary authority dependent Regulation 1830/2003 , said "the traceability of GMOs, and Regulation 1829/2003 , said "on the labeling of GMOs .

Searching

Of research focuses on plants or micro-organisms genetically modified to remediate contaminated soils and more generally to eliminate environmental contaminants (nitrate traps, etc..) .

Some research also aims to produce low-cost materials scarce or expensive, such as hydrocarbons from ordinary nutrients. Thus, a French company based in the Genopole of Evry (Essonne) announced October 6, 2010 have made the bacteria capable of synthesizing the isobutene from glucose .

Regulation and use of GM crops worldwide

Main article: Regulation of GMOs.

The regulation of genetically modified organisms varies widely by country; wide range of legal measures have been taken worldwide for research, production, marketing and use of GMOs in their various fields of application (agriculture, Medical ...). The regulations in Europe is more restrictive than in North America and in emerging countries , as regards their farms, their marketing and food consumption.

The European Food Safety Authorities: Roles and functions

In Europe, the rules regulating the presence of GMOs in the food market is subject to the Directive 2001/18/EC amended and clarified by regulations 1830/2003 and 1829/2003 . The Directive 2001/18/EC (known as "the deliberate release of GMOs ") regulates the deliberate release of GMOs into the environment (field crops for research or commercial, transport, handling ...). The Regulation 1830/2003 (called "on the traceability / A> GMO ") applies to GMOs intended for marketing either as food for humans and / or animal or industrial products. Are affected by this regulation, the genetically modified seeds, their products, derivatives of these products. Excluded are GMOs for medical and / or veterinarian. It is relayed by the Regulation 1829/2003 EU , when a company wants to market a genetically modified plant as products or in products, it addresses one of the governments of European countries. The latter, through the competent authority of Aboriginal health security, reviews the file provided by the company. In France , the jurisdiction falls under AFSSA which works in collaboration with the CGB . Following this observation, the authority said government safety issues an opinion which may be favorable or not. If unfavorable opinion, the company can seize the competent authority of another state which will in turn issue an independent opinion of the first. In the case of a favorable opinion, the state that received the application (called "notification") issued the report and inform the other Member States through the European Commission. These institutions will examine in turn the evaluation report, issue any comments and / or objections. In the absence of objection, the competent authority which carried out the initial assessment grants permission to market the product. It is placed on the market throughout the EU, in compliance with any conditions imposed by the authorization. The permit has a maximum of ten years and may be renewed under certain conditions. In the presence of objection (s), the procedure provides for a conciliation phase among Member States, the Commission and the notifier (company). If at the end of the conciliation phase the objections are maintained, the Commission seeks the opinion of the EFSA ). It is re-examining the report and an opinion . The Commission submits a draft decision to the Regulatory Committee composed of representatives of Member States. If the Committee gives a favorable opinion, the Commission adopted the decision. Otherwise, the draft Decision is submitted to Cabinet for adoption or rejection by qualified majority. The Council must act within three months, otherwise the Commission adopts the decision.

May 12008 , 23 PGM for food, feed and / or import and processing are allowed in the European Union: 12 corn , 5 cotton , 3 soy , 1 beet , 1 eyelet .

experimental in the environment must obtain written permission from the competent national authority of the Member State in whose territory the release will be experimental. This authorization is issued on the basis of an assessment of risks posed by the PGM to the environment and health human. The other Member States and the European Commission may make observations that the competent national authority consider.

May 1 2008, 4 PGM for cultivation is permitted. This maize MON 810 from Monsanto , corn T25 Bayer , herbicide-tolerant and 2 eyelets Florigene. . In June 2009 , approval for cultivation of MON810, valid for 10 years, having expired, the EU must decide on its possible renewal.

A 2004 survey of Friends of the Earth , an NGO, is the possibility of conflicts of interest within the EFSA and raises the issue of independence of the evaluation committee . In July 2009, Corinne Lepage , a founding member of the Research Committee and Independent Information on Genetic Engineering (CRIIGEN) , Association study of the impact of gene technology on living, stressed that the EFSA opinion on studies with "confidential information remains classified, despite the wording of the EU Directive on GMOs" .

The use of GMOs is permitted in all countries of the world on the basis of experimental results showing no danger to human and animal health. In general, the principle of substantial equivalence is the starting point for assessing product safety. Plant non-GMO is compared to the GM plant because all plants have toxic qualities and / or allergies. The assessment ensures that the amendment does not induce toxic effects and / or allergenic new (or increase these effects). However, toxicology tests are also performed in addition. These tests help to ensure the safety of GMOs. In many European countries including France , the principle of equivalence is applied and is also an element in the overall assessment: GMOs received a favorable opinion if all the tests used (including toxicology and allergenicity ) do not indicate a potential hazard. To date, the toxicological and allergenicity tend to prove that GM crops intended for human consumption are safe for human and animal health (Hrout 2003 , Hrout et al. 2005 , and Guicheney Hrout- al 2009 ). Some scientists dispute the validity of these tests, accusing them of not being inquisitive enough. This is the case Sralini et al., Which rely on to do an analysis of toxicology tests maize MON 863 . Health agencies responsible for scientific management of food risks that meet their objections are unfounded .


The World Trade Organization allows the restriction of imports in the case of a "protection against risks to food safety and the risks of invasive species from genetically modified plants. " , but these conditions are not met, according to the WTO, the dispute between the producing countries (USA, Canada, Argentina) to the EU . The European community has pledged to abide by WTO rules on GMOs, by February 2008 .

Areas of GMO crops

Growing areas of GMO plants in 2005 in orange, the 5 countries growing more than 95% of agricultural GMOs commercialized in 2005, hatched, other countries marketing of GMOs in 2005. The points denote the country allowing field experiments
Related article: Cultivated GMOs.

In 2009 , according to ISAAA , 14 million farmers using GMOs, 90% are farmers in developing countries. The area planted with transgenic crops worldwide would reach 134 million hectares, an increase of 7% over 2008. 8 countries with the greatest product in 2009 were the United States (47.8%), Brazil (16%), Argentina (15.9%)., India, Canada, China, Paraguay and South Africa. Also according to the ISAAA , the share of GM crops in agricultural production in the European Union , one of the largest in the world, is very low. And transgenic crops in the EU fell between 2008 and 2009 by 11%, from 106,739 ha to 94,708 ha .

The GMO debate

The introduction of biotechnology represented by GMOs has met with resistance and opposition that have continued to fuel the debate from the late 1990s . The intensity of this opposition, whether expressed in populations affected by the consumption of products derived from this technology , is variable depending on the country. Scalded by health crises like the mad cow , the government has, at least in Europe , sought to address concerns expressed by their public opinion by proposing moratoriums and regulations intended to allow the isolation of traditional crops and GM crops. However, whereas seed dispersal and probable cause is a risk , anti-GMO accordingly continue their struggle , embodied and symbolized in France by the movement of " volunteer reapers ".

Fruits of genetic engineering, GMOs are presented by its advocates as a cure for world food problems including their ability to overcome or live with difficult growing conditions and provide better returns. They would also reduce in part the use of pesticides on crops. Despite the concurrence of the international scientific bodies who claim that GMOs currently approved for production and food does not pose health and environmental problems . Thus, while the vast majority of GM crops grown worldwide are "plant pesticides", that is to say they produce an insecticide as in the case of MON863 and MON 810 , or they tolerate a herbicide as in the case of NK 603 , they are not tested as such.

Proponents of GMOs and researchers who are developing these techniques consider that it is only prolonging the action of man, in his gradual mastery of agriculture and the farm during his evolution, has always sought to select and cross species employed . It is to them a progress of science to control his environment by man. Their opponents believe that a GMO is radically different from other organizations that changed their genetic heritage are not by genetic engineering operation . The techniques used combine and transform the genetic information of organisms beyond the species barrier.

Ethically, the development of GMOs is part of the controversy surrounding the patenting of life. Patenting by large industry groups which gives them exclusive rights over a portion of the gene pool is very critical, beyond the circles anti-GMO. Opponents of GMOs fear a takeover of more and more of the food industry on the universal common good for agriculture that are natural species .

Economically, the International Service for the Acquisition of Agri-biotech Applications (ISAAA), an organization specializing in the development of GMOs in developing countries, believes that the wealth created in 2005 by GMOs to farmers is a gain of about 4%, and that prices should be brought down as is the case for soybeans . For supporters of peasant agriculture , and in the context of promotion of organic farming , cultivation of GMOs appears as the last card of industrial agriculture. They see the development of GMOs strengthening the grip of the food industry on global agriculture that is opposed by them in part to the development of food sovereignty in countries where agricultural production is mainly for the export . Moreover, many countries of Africa (among the exceptions are the South Africa , the Egypt and Burkina Faso , GMO-producing countries ) themselves have strongly denounced in a statement in June 1998 the use that was made by the company Monsanto , and their image of poverty in order to help promote GMOs in industrialized countries. Especially when they complained that "images of poverty and hunger in our country are used by multinationals to promote a technology that is neither safe nor environmentally friendly and do we benefit in any way" .

References

Notes

  1. for rBGH Recombinant Bovine Growth Hormone, or rBST for Recombinant Bovine Somatotropin (term used by the company Monsanto )
  2. WHO wrote that "there has never been shown that their consumption by the general public in countries where they have been approved had had any effect on human health" WHO, answers to questions about GMOs , Q8. Accessed May 12, 2008
  3. The potential is the theoretical possibility to change a character by character, in the gene, whereas traditional methods for improving organizations based on the character selection visible, without control at the gene concerned, and neighboring genes
  4. The International Council for Science , which brings together authoritative scientific organizations in all areas, considered in a study published in 2003, the consumption of GMOs is safe contemporaries: "Currently available are Genetically Modified foods safe to eat. Food Safety Assessment by the National Regulatory Agencies in Countries Have SEVERAL Currently available GM foods Deemed to Be as safe to eat as Their Conventional and share Suitable for human consumption. This View is shared by SEVERAL Intergovernmental Agencies, Including The FAO / WHO Codex Alimentarius Commission on food safety, Which Has 162 Member Countries, the European Commission (EC), & the Organization for Economic Cooperation and Development (OECD). "(En) New Genetics, Food and Agriculture: Scientific Discoveries - Societal Dilemmas , International Council for Science, May 2003 , p.8

References

  1. Sralini Gilles-Eric, These GMOs are changing the world, Champs Flammarion, p.9.
  2. Jean-Paul Renard, " Text of the 28th conference of the University of All Knowledge, Cloning "on National Computer Center for Higher Education, 28. Accessed April 23, 2009
  3. site of the Ethics Committee, Science and Technology ( Quebec ): introduction , bibliography
  4. The Independent Science Panel on GM Final Report
  5. ISAAA data in 2010 See also

    Bibliography

    Reference works

    • Dominique de Vienne, molecular markers in genetics and biotechnology, INRA Editions, 1998
    • Sandy Primrose, Richard Twyman, RW Old, Old Bob, Lionel Domenjoud, Principles of Genetic Engineering, Oxford University Press 2004

    Studies

    • Hrout-Guicheney, C. Rouqui, D. Zhou, J., Freyssinet, M., Currier, T., Martone, A., van Hooren, A., Hendrickx, K., van der Klis, RJ., Rouan, D. Safety Evaluation of the double mutated maize 5 enol pyruvylshikimate 3 phosphate synthase (2mEPSPS) That confer glyphosate tolerance to herbicide in transgenic plants. Regulatory Toxicology and Pharmacology. 54:143-153
    • Hrout, C., Esdaile, DJ, Mallyon, BA, Debruyne, E., Schulz, A., Currier, T., Hendrickx, K., van der Klis, R. and Rouan, D. 2005. Safety Evaluation of the phosphinothricin acetyltransferase proteins encoded by the pat and bar sequences The confer tolerance to That glufosinate ammonium herbicide in transgenic plants. Regulatory Toxicology and Pharmacology. 41: 134-149.

    Trial


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