2. DECLARATION
The investigation presented in this Project work entitled “process of
development of genetically modified organism” is our own
work under the guidance of smt. SUBHALAXI JENA lecture in our
Department of Zoology, D.K. College, Jaleswar, Balasore. This work has
not been previously submitted by anybody else for any purpose. We hereby
submit this Project report for the partial fulfillment of Degree Examination of
Zoology Discipline Specific Elective Course paper DSE-4 of UG 6Th
Semester Practical Examination under F.M. University, Balasore for the
session 2019-12 A.D.
Full Signature of the student
Class : 4Th Semester Zoology (H)
Roll No :
Date :
3. ACKNOWLEDGEMENTS
I express my indebtedness and gratitude to my guide teacher, smt.
Subhalaxmi Jena lecture, Department of Zoology, D.K. College, Jaleswar,
Balasore. for suggesting the topic and proper guidance for this project work
entitled “process of development of genetically modified
organism”.
I am grateful to Mr. H. S. Jena, Demonstrator, Dept. of Zoology
Ch. S. C. Nanda, Principal, D.K. College, Jaleswar, Balasore for their generous
gesture by way of providing necessary facilities to complete this project
work.
It is almost impossible to acknowledge the various help extended by
the people of this area I dealt with to complete the project. However, I
extend my gratitude to all of them for their help during the work. I am also
thankful to my friends of the same honours for their cooperation.
Full Signature of the student
Class : 6Th
Semester Zoology(H)
Roll No :
Date :
4. Dr. Dharani Dhar Ghosh, Dinakrushna College,
Reader, Dept. of Zoology Jaleswar, Balasore,
Odisha.
Certificate
This is to certify that the project work entitled “process of
development of genetically modified organism” submitted by
Sri Subhrajyoti Sahoo bearing Roll no 5906B16020 of UG 6Th
Semester
Zoology Honours for the partial fulfillment of CC-XIII Examination under F.M.
University, Balasore for the session 2019-20 A.D. is based on the result of
bonafide project work carried out under my supervision.
(Dr. D. D. Ghosh)
Asso. Prof and Head
Department of Zoology,
D.K.College,Jaleswar.
6. ABSTRACT
A genetically modified organism is any organism whose genetic material has
been altered using genetic engineering techniques. A wide variety of organisms have been
genetically modified, from animals to plants and microorganisms. Genes have been
transferred within the same species, across species and even across kingdoms. Genetic
engineers must isolate the gene they insert into the host organism and combine it with
other genetic elements. Bacteria are the easiest organisms to engineer and have been used
for research, food production, industrial protein purification and agriculture. There is
potential to use them for environmental, purposes or as medicine. Genetically modified
crops are publicly the most controversial genetically modified organism. Animals are
generally much harder to transform and the vast majority are still at the research stage.
Mammals are the best model organisms for humans, making ones genetically engineered
to resemble serious human diseases important to the discovery and development of
treatments. Human proteins expressed in mammals are more likely to be similar to their
natural counterparts than those expressed in plants or microorganisms. Livestock are
modified with the intention of improving economically important traits such as growth-
rate, quality of meat, milk composition, disease resistance and survival. Genetically
modified fish are used for scientific research, as pets and as a food source. Genetic
engineering has been proposed as a way to control mosquitos, a vector for many deadly
diseases. Although human gene therapy is still relatively new, it has been used to
treat genetic disorders such as severe combined immunodeficiency. Transgenic animals
are routinely used in the laboratory as models in biomedical research. Over ninety-five
percent of those used are genetically modified rodents, predominantly mice. They are
important tools for researching human disease, being used to understand gene function
in the context of disease susceptibility, progression and to determine responses to a
therapeutic intervention. Transgenic animals are also being explored as a means to
produce large quantities of complex human proteins for the treatment of human disease.
Such therapeutic proteins are currently produced in mammalian cell-based reactors, but
this production process is expensive.
7. INTRODUCTION:-
A transgenic animal is one that carries a foreign gene that has been deliberately
inserted into its genome. The foreign gene is constructed using Recombinant DNA
methodology. In addition to the gene itself, the DNA usually incorporated into the DNA of the
host and to be expressed correctly by the cells of the host. Transgenesis has now become a
powerful tool for studying the gene expression and developmental processes in higher
organisms to improvement in their phenotype. Transgenic animals serve as models for
understanding the human disease. Several proteins are produced by transgenic animals
which are importance for pharmaceutical applications. The transgenic animals are a part of
the lucrative worldwide biotechnology industry with benefits to mankind. Genetically
modified organism, organism whose genome has been engineered in the laboratory in order
to favor the expression of desired physiological traits or the production of desired biological
products.
In conventional livestock production, crop farming, and even pet breeding, it has long
been the practice to breed select individuals of a species in order to produce offspring that
have desirable traits. In genetic modification, however, recombinant genetic technologies are
employed to produce organisms whose genomes have been precisely altered at the molecular
level, usually by the inclusion of genes from unrelated species of organisms that code for traits
that would not be obtained easily through conventional selective breeding.
Since the 1980s transgenic mice have become a key model for investigating disease.
Mice are the model of choice not only because there is extensive analysis of its completed
genome sequence, but its genome is similar to the human. Moreover, physiologic and
behavioral tests performed on mice can be extrapolated directly to human disease. Robust
and sophisticated techniques are also easily available for the generic manipulation of mouse
cells and embryos. Another advantage of mice is the fact that they have a short reproduction
cycle. Other transgenic species, such as pig, sheep and rats are also used, but their use in
pharmaceutical research has so far been limited due to technical constraints. Recent
technological advances, however, are laying the foundation for wider adoption of the
transgenic mice.
The definitions focus on the process more than the product, which means there could
be GMOS and non-GMOs with very similar genotypes and phenotypes. This has led scientists
to label it as a scientifically meaningless category, saying that it is impossible to group all the
different types of GMOs under one common definition. It has also caused issues
for organic institutions and groups looking to ban GMO sit also poses problems as new
processes are developed. The current definitions came in before genome editing became
popular and there is some confusion as to whether they are GMOs. The EU has adjudged that
they are changing their GMO definition to include "organisms obtained by mutagenesis”. In
contrast the USDA has ruled that gene edited organisms are not considered GMOs.
8. REVIEW OF LITERATURE:-
1. first genetically modified organism in 1973. By Herbert Boyer and Stanley Cohen.
Abstract: -
Humans have domesticated plants and animals since around 12,000 BCE, using selective
breeding or artificial selection (as contrasted with natural selection). They took a gene from a
bacterium that provided resistance to the antibiotic kanamycin, inserted it into a plasmid and
then induced other bacteria to incorporate the plasmid. The bacteria that had successfully
incorporated the plasmid was then able to survive in the presence of kanamycin. Boyer and Cohen
expressed other genes in bacteria. The process of selective breeding, in which organisms with
desired traits (and thus with the desired genes) are used to breed the next generation and
organisms lacking the trait are not bred, is a precursor to the modern concept of genetic
modification. Various advancements in genetics allowed humans to directly alter the DNA and
therefore genes of organisms.
2. GENETICALLY MODIFIED ORGANISMS AND CHALLENGES by Bishnu Karki.
Abstract: -
Genetically modified organisms have been developed by application of advanced
techniques of genetic engineering. GM crops offer distinctive advantages like insects, weed,
disease and drought resistance, better nutritional value and higher yield. There are several
environmental and public issues concerning the GMO’s. Overall, genetic engineering of the
organisms, plants and animals is accepted conditionally; the gene inserted and its products
should be carefully assessed both for human and environmental safety before release into the
nature and to the public market. In many countries in the world, especially, those is the
European Union, GM food is still considered as undesirable. Mandatory labeling is required
when more than 1% of any ingredient of food which originates from the GMO. Thus, there are
several researches are on progress for development of the valid GMO detection method.
3. GENETICALLY MODIFIED ORGANISMS(GMOs) & AGRICULTURE trade by Michelle
Cynthia john.
Abstract: -
9. AIMS AND OBJECTIVE
1. Method of production of Genetically Modified Organism.
2. Types of method
3. Method implication in mice (Transgenic mice).
4. Method implication in sheep (Transgenic sheep).
10. Method of production of GMO:-
The production of transgenic animals is the introduction of a foreign gene or genes into an
animal by transgenesis. The foreign genes which are transferred to the animal are known as
transgene. The foreign genes must be transmitted through the germ line, so that every cell,
including germ cells, of the animal contain the same modified genetic material. Germ cells are cells
whose function is to transmit genes to an organism’s offspring.
There are three basic methods of producing transgenic animals:
▪ DNA microinjection
▪ Retrovirus-mediated gene transfer
▪ Embryonic stem cell-mediated gene transfer
Gene transfer by microinjection is the predominant method used to produce transgenic
farm animals. Since the insertion of DNA results in a random process, transgenic animals are
mated to ensure that their offspring acquire the desired transgene. However, the success rate of
producing transgenic animals individually by these methods is very low and it may be more
efficient to use cloning techniques to increase their numbers.
1. DNA Microinjection method:-
This method involves the direct microinjection of a chosen gene construct from another
member of the same species or from a different species, into the pronucleus of a fertilized ovum.
It is one of the first methods that proved to be effective in mammals. It was first discovered by
Gordon and Ruddle in 1981. The introduced DNA may lead to the over- or under-expression of
certain genes or to the expression of genes entirely new to the animal species. The insertion of
DNA is, however, a random process, and there is a high probability that the introduced gene will
not insert itself into a site on the host DNA that will permit its expression. The manipulated
fertilized ovum is transferred into the oviduct of a recipient female, or foster mother that has
been induced to act as a recipient by mating with a vasectomized male. A major advantage of
this method is its applicability to a wide variety of species.
11. 2. Retrovirus-Mediated Gene Transfer method:-
To increase the probability of expression, gene transfer is mediated by means of a carrier
or vector, generally a virus or a plasmid. Retroviruses are commonly used as vectors to transfer
genetic material into the cell, taking advantage of their ability to infect host cells in this way.
Offspring derived from this method are chimeric, i.e., not all cells carry the retrovirus.
Transmission of the transgene is possible only if the retrovirus integrates into some of the germ
cells.
For any of these techniques the success rate in terms of live birth of animals containing
the transgene is extremely low. Providing that the genetic manipulation does not lead to
abortion, the result is a first generation (F1) of animals that need to be tested for the expression
of the transgene.
Depending on the technique used, the F1 generation may result in chimeras. When the
transgene has integrated into the germ cells, the so-called germ line chimeras are then inbred
for 10 to 20 generations until homozygous transgenic animals are obtained and the transgene is
present in every cell. At this stage embryos carrying the transgene can be frozen and stored for
subsequent implantation.
12. 3. Embryonic Stem Cell-Mediated Gene Transfer method:-
This method involves prior insertion of the desired DNA sequence by homologous
recombination into an in vitro culture of embryonic stem (ES) cells. Stem cells are
undifferentiated cells that have the potential to differentiate into any type of cell
(somatic and germ cells) and therefore to give rise to a complete organism. These
cells are then incorporated into an embryo at the blastocyst stage of development.
The result is a chimeric animal. ES cell-mediated gene transfer is the method of
choice for gene inactivation, the so-called knock-out method.
This technique is of particular importance for the study of the genetic control of
developmental processes. This technique works particularly well in mice. It has the
advantage of allowing precise targeting of defined mutations in the gene via
homologous recombination.
13. 1. TRANSGENIC MICE :-
As already started, mouse is the animal of choice for choice for transgenic experiments.
Being a small animal, it can be handled, and mouse is regarded as researcher-friendly by
biotechnologists. Another important reason of choosing mice for transgenic experiments is it
produces more eggs unlike the large domestic animals. In the last two decades, hundred of
different genes have been introduced into the various mouse strains. And as such, the
methodology of transgenesis is well developed with laboratory mouse.
Transgenic mice have significantly contributed to the understanding of molecular biology,
genetics, immunology and cancer, besides creating animal models for several human genetic
diseases.
There are three methods for introducing a foreign gene into mice, and in fact the same
methods are applicable to other animals as well.
A. Retroviral vector method.
B. Microinjection method.
C. Embryonic stem cell method.
It may be noted here that the term transfection is used for introducing a foreign gene into
animals. This is quite comparable to transformation that is carried out in lower organisms
1. RETROVIRAL VECTOR METHOD: -
The transfer of small pieces (8 kb) of DNA can be effectively carried out by retroviruses.
This method, however, is unsuitable for transfer of large genes. Further, even for small genes,
there is a risk of losing some regulatory sequences. Above all, the biggest drawback is the risk of
retroviral contamination in the products, obtained from transgenic animals. Because of these
limitations, the retroviral methods not in regular use for transgenesis.
14. 2. MICROINJECTION METHOD:-
The introduction of DNA by microinjection method involves the following steps.
1. The young virgin female mice (4-5 weeks age) are subjected to superovulation. This is
achieved by administration of follicle-stimulating hormone, followed by human
chorionic gonadotropin. The super ovulated mouse produces 30-35 eggs (instead of
normal 5-10 eggs).
2. The above female mice are mated with males and sacrificed on the following day. The
fertilized eggs removed from the fallopian tubules.
3. By micromanipulation using a micro-injection needle and pipette, the DNA is injected
into the male pronucleus of the fertilized egg. Adequate care must be taken to ensure
that while the elastic nuclear membrane is punctured, the needle does not touch the
nucleoli. A dissection microscope can be used for identifying the male pronucleus
(large in size) and for microinjection.
4. The eggswith transgenes are kept overnight in an incubator to develop to a 2-cell stage.
These eggs are then implanted micro surgically into a foster mother i.e., pseudo-mouse
pregnant female mouse which has been mated the previous might with vasectomized
(or infertile) male. The foster mother can deliver pups after 3 weeks of implantation.
The presence of transgene in the pups can be identified by polymerase chain reaction or
Southern blot hybridization.
The mouse carrying the foreign gene is the transgenic founder from which pure transgenic
lines can be established.
The microinjection method involves several steps and none of them is 100% efficient for
any animals to develop into transgenic animal. In case of mouse, it was found that about 65% of
the fertilized eggs survive microinjection procedure, about 25% of the implanted eggs develop
into pups, and only 25% of them are transgenic. Thus, if one starts with 1000 fertilized eggs, only
30 to 50 transgenic pups may be produced i.e., 3-5% of the inoculated eggs develop into
transgenic animals.
15.
16. 3. EMBRYONIC STEM Cell METHOD: -
Cells from the inner cell mass of the blastocyst stage of a developing mouse embryo can
proliferate in cell culture. These cells, referred to as pluripotent embryonic stem cells, are capable
of differentiating into other types of cells (including germ line cells) when transferred to another
blastocyst embryo.
The embryonic stem cell technology basically involves the introduction of a foreign DNA
into ES cell. Embryonic stem cells in culture can be subjected to genetic manipulations without
changing their pluripotency. Foreign DNA can be introduced into ES cells by electroporation or
microinjection. The desired genetically engineered cells with transgene can be identified by a
selection procedure using a marker gene or PCR gene analysis. The transfected cells can be
cultured, introduced (by micro injection) into blastocyst and then implanted into foster mother.
By this way, transgenic founder mice are produced. Transgenic lines can be established by
suitable breeding strategies of the founder mice.
The methods are:-
1. Purify the undigested plasmid containing the transgene construct by either CsCl gradient or by
a membrane column method (e.g., Qiagen Plasmid Maxi/Midi Kit or Promega Wizard Plasmid
Purification Kit).
2. Restriction digest the vector with appropriate restriction enzymes to completely release and
separate the transgene from vector/prokaryotic sequence. The construct must therefore be
designed with unique restriction enzyme(s) at each terminus of the transgene (at both junctions
with the prokaryotic backbone), permitting isolation by restriction enzyme digest.
3. Electrophorese the products of the restriction digest through a <1.25% agarose gel in 1x
Modified TAE buffer.
4. Using a transilluminator, excise the DNA band with a razor and place into the Montage DNA
Gel Extraction Device. The volume should be less than 100 mg.
5. Close lid and spin assembled device for 10 minutes at 5000x g. When finished, discard the
Sample Filter Cup and Gel Nebulizer.
6. Determine the volume of my sample. Add 1/10 volume of 3M Sodium Acetate pH 5.5 and 2.5
volumes 100% ethanol. Mix and centrifuge at 15,000x g for 15 minutes. Wash with 70%
ethanol, air dry, and resuspend in Embryo Max Injection Buffer. Concentration should be
greater than 2.0 ng/ul.
17. SELECTION OF TRANSGENE CONTAINING CELLS
Several strategies have been developed for the selection of transgene containing cells. The
importance is briefly described
Selection by use of marker gene coding for thymidine kinase: it is worthwhile to know the
role of thymidine kinase to understand its utility as a marker gene. There are two pathways for
the synthesis of deoxyribonucleotides (dATP, dGTP, dCTP, dTTP), the basic units of DNA
structure. One is the salvage pathway that recycles the degraded nitrogenous bases formed from
DNA. The other alternate pathway is an endogenous synthetic pathway from different precursors
(glycine, aspartate, glutamine, methyl tetra-hydrofolate etc.).
The enzyme thymidine kinase (TK) is involved in the salvage pathway. TK phosphorylates
thymidine to produce thymidine monophosphate(dTMP) which is finally converted into
thymidine triphosphate(dTTP).
The gene that encodes the enzyme thymidine kinase can be used as a marker to determine
whether the transgene has been inserted. The mammalian cells are capable of synthesizing dTTP
by salvage pathway and endogenous synthetic path way.
The cell lacking TK gene cannot produce dTTP. If such cells are cultured in a HAT medium
containing hypoxanthine (H), aminopterin (A), and thymidine (T), they cannot grow and
therefore die. This is because thymidine cannot be utilized in the salvage pathway due to lack the
enzyme thymidine kinase. Further, aminopterin blocks the endogenous pathway (by inhibiting
the enzyme dihydrofolate reductase, required for one carbon metabolism).
If a transgene is joined to a TK gene, inserted into a mammalian cell. And logically, the cells
that survive in HAT medium carry the trans gene. In this fashion, thymidine kinase can be
effectively used as a marker gene.
There are other enzymes that serves as markers for identifying transgene insertion. This
include dihydrofolate reductase (resistant to methotrexate) and neomycin phosphotransferase
(resistant to antibiotic G418) and PCR analysis for selecting transgene containing cells. The last
one is a more direct and recent method, and is successfully used for detecting transgene
containing cells.
19. APPLICATIONS 0f TRANSGENIC MICE :
Mouse, although not close to humans in its biology, has been and continues to be the
exploited animal model in transgenesis experiments. The common feature between man and
mouse is that both are mammals. Transgenic mice are extensively used as animal models for
understanding human diseases and for the production of therapeutic agents, Adequate care,
however, must be exercised before extrapolating data of transgenic mice to humans.
Mouse models for several human diseases (cancers, muscular dystrophy, arthritis,
Alzheimer’s disease, hypertension, allergy, coronary heart disease, endocrine diseases,
neurodegenerative disorders etc.) have been developed. A selected few of them are briefly
discussed.
i. THE HUMAN MOUSE
The transgenic mice with human immune system were produced, and they are commonly
referred to as human mice. For this purpose, mice with severe combined immune deficiency
(SCID-a condition characterized by total lack of immune system cells) were chosen. Human
thymus tissue from an aborted fetus was transplanted under the capsule membrane of the kidney
of the mouse. Human lymph node was placed on the opposite kidney of the mouse. After about a
week, immature immune cells (T-lymphocytes) from a human fetus were injected into the mouse
tail vein. These lymphocytes enter the thymus tissues under the kidney and matured to T-
lymphocytes. The so produced T-lymphocytes enter the circulation and in the lymph node
(present under the second kidney), they multiply to form a full-pledged functional immune
system. It takes about two weeks after the transplant for the mice to display the human immune
system (characteristics of both T-lymphocytes and B- lymphocytes).
The human mouse, being a close animal model for human immune system is a boon for
immunologists, particularly working on AIDS. This is because the various immunological aspects
of AIDS including the possible development of AIDS vaccine can be explored by using human
mouse.
ii. THE ALZHEIMER’S MOUSE
Alzheimer’s disease affects about 1% of the population between 60-65 years old, and
about 30% of the population over 80 years old. This disease is characterized by progressive loss
of memory and personality change (decline to think, judgement etc.). the postmortem analysis of
brains of Alzheimer’s patients revealed plaques of dead nerve cells entangled in a protein called
amyloid. This protein was purified and its amino acid sequence determined. Later, amyloid
precursor protein (APP) and itsgene sequence were also identified. Alzheimer’sis more prevalent
in some families, clearly indicating a genetic basis for this disease.
Transgenic mice were developed by introducing amyloid precursor gene into fertilized
egg cells of mice. The synthesis of human amyloid protein and its accumulation as typical plaques
in the mice brain were observed. The Alzheimer’s mouse is very useful in understanding the
pathological basis of the disease. Certain mutation in APP gene, and the environment of some
other genes are believed to be responsible for Alzheimer’s disease.
20. iii. THE ONCOMOUSE
The animal model for cancer is the oncomouse (onco refers to cancer). First develop for
developed breast cancer, the onco is useful for understanding of cancer and evolving modalities
for cancer therapy.
The oncogene c-myc in association with mouse mammary tumor (MMT) virus was found
to be responsible for breast cancer in mammals. Transgenic mice were produced by introducing
chimeric DNA consisting of c-myc gene and sections MMT virus into fertilized mouse egg cells.
Breast cancer developed in adult female mice and the trait was passed on to the offspring.
Oncomouse (the mouse that is genetically altered and is susceptible for cancer) was
patented by U.S. Patent office in 1988. In fact, it was very first animal to be patented.
iv. THE PROSTATE MOUSE
The prostate gland, surrounding the urethra of males is responsible for secreting semen
fluid. In the older men, particularly above 60 years of age, prostate gland begets enlarged and may
become cancerous. The oncogene for prostate cancer was identified (int-2). A chimeric DNA by
joining int-2 with viral promotor was prepared and introduce into fertilized mouse eggs. In the
transgenic mice so developed, enlargement of prostate gland was observed. There prostate mice
were also patented in 1991.
v. THE KNOCKOUT MICE
The basic principle underlying gene knockout have been described. Several knockout
mice have been developed. It is not an exaggeration that the knockout mice have become as
common as test tube in the laboratory for a biotechnologist.it must noted that not all the knockout
mice are immediately useful for human health and welfare. A selected few of the knockout mice
are described.
vi. SCID MOUSE
Severe combined immunodeficiency (SCID) is a condition with a total lack of immune
system. SCID mice were developed my eliminating a single gene and the resultant mice lost the
ability to produce B-lymphocytes and T-lymphocytes. The human mouse was later developed
from the SCID mouse.
vii. TRANSGENIC MICE FOR HUMAN DISEASES
Transgenic mice are important for the development of therapeutic drugs and possible
gene therapies, besides the understanding of human disease. Many transgenic mice with human
disease equivalents have been developed.
21. Transgenic sheep
Transgenic experiments in sheep mostly involve the development of mammary glands as
bioreactors for the production of proteins for pharmaceutical use. This is possible despite fact
that quantity of milk produced by sheep is less than that of dairy cattle. some other proteins
produced by sheep have good pharmaceutical use.
Keratin is the wool protein with highly crosslinked disulfide bridge. For good production
of quality wool, the amino acid cysteine is required in large quantities. However, cysteine supply
to sheep is always inadequate, since the microbes harboring the rumen utilize it and release the
form of sulfide. This problem can be overcome by producing transgenic sheep containing
bacterial genes for synthesis of cysteine. Thus, good supply of cysteine to the improves the quality
and quantity of wool.
The rate of transgenesis in sheep is very low (0.1% to 0.2%). This can be improved, if only
transgenic viable embryos are transferred to surrogate ewes (female sheep). Embryos at 8-16
cell stage can be split into two parts, one foe continued culture and other for detection of
integrated genes using polymerase chain reaction (PCR). Although microinjection is the most
common method for DNA delivery, gene targeting may be increasingly used in future. In this
approach, embryonic stem (ES) cells in culture are transfected with a vector which targets the
gene to a particular site by homologous recombination.
Recombination DNA technique can also be used to increase the ability of sheep for wool
growth. For this purpose, genes essential for synthesis of some important amino acid found in
keratin proteins in wools, have been cloned and introduced in embryos to produce transgenic
sheep.
22. CONCLUSION
We reaffirm our view that Genetically modified organism represents an important new
technology which ought to have the potential to do much good in the world provided that proper
safeguards are maintained or introduced. All those who are involved in developing the new
technology, whether they are researchers in the public sector, in agrochemical or agricultural
businesses or farmers, or food manufacturers and retailers need to recognize and accept a very
broad responsibility to the public.
They need to ensure that ethical concerns are taken account of, that their new technologies
and products are safe for human consumption and avoid further harm to the environment, that
the potential of GM technology is harnessed to meet the most urgent food needs of the world as
well as commercial benefit, that impartial information is made widely available to the public and
that consumer choice is fully respected.
Many objections have been raised over the development of GMO's, particularly their
commercialization. Many of these involve GM crops and whether food produced from them is safe
and what impact growing them will have on the environment. Other concerns are the objectivity
and rigor of regulatory authorities, contamination of non-genetically modified food, control of
the food supply, patenting of life and the use of intellectual property rights. Although there is
a scientific consensus that currently available food derived from GM crops poses no greater risk
to human health than conventional food, GM food safety is a leading issue with critics.
Gene flow, impact on non-target organisms and escape are the major environmental
concerns. Countries have adopted regulatory measures to deal with these concerns. There are
differences in the regulation for the release of GMOs between countries, with some of the most
marked differences occurring between the USA and Europe. One of the key issues concerning
regulators is whether GM food should be labeled and the status of gene edited organisms
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