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Purpose of gene cloning To study genes in the laboratory, it is necessary to have many
copies on hand to use as samples for
different experiments. Such experiments include Southern or Northern blots, in which genes
labeled with radioactive or fluorescent chemicals are used as probes for detecting specific
genes that may be present in complex mixtures of DNA. Cloned genes also make it easier to
study the proteins they encode. Because the genetic code of bacteria is identical to that of
eukaryotes, a cloned animal or plant gene that has been introduced into a bacterium can
often direct the bacterium to produce its protein product, which can then be purified and used
for biochemical experimentation. Cloned genes can also be used for DNA sequencing, which
is the determination of the precise order of all the base pairs in the gene. All of these
applications require many copies of the DNA molecule that is being studied. Gene cloning
also enables scientists to manipulate and study genes in isolation from the organism they
came from. This allows researchers to conduct many experiments that would be impossible
without cloned genes. For research on humans, this is clearly a major advantage, as direct
experimentation on humans has many technical, financial, and ethical limitations. Importance
in medicine and industry
The ability to clone a gene is not only valuable for conducting biological research. Many
important pharmaceutical drugs and industrial enzymes are produced from cloned genes.
For example, insulin, clotting factors, human growth hormone, cytokines cell growth
stimulants, and several anticancer drugs in use are produced from cloned genes. Before the
advent of gene cloning, these proteins had to be purified from their natural tissue sources, a
difficult, expensive, and inefficient process. Using recombinant methods, biomedical
companies can prepare these important proteins more easily and inexpensively than they
previously could. In addition, in many cases the product that is produced is more effective
and more highly purified. For example, before the hormone insulin, which many diabetes
patients must inject, became available as a recombinant human protein, it was purified from
pig and cow pancreases. However, pig and cow insulin has a slightly different amino acid
sequence than the human hormone. This sometimes led to immune reactions in patients.
The recombinant human version of the hormone is identical to the natural human version, so
it causes no immune reaction. Gene cloning is also used to produce many of the molecular
tools used to study genes. Even restriction enzymes, DNA ligase, DNA polymerases, and
many of the other enzymes used for recombinant DNA methods are themselves, in most
cases, produced from cloned genes, as are enzymes used in many other industrial
processes.
These benefits and risks must be weighed in light of their moral. during. that it represents a
slippery slope to a dehumanized future. There is also current research into gene therapy for
embryos before they are implanted into the mother through invitro fertilization. The hope is
that soon. a fetus w/ a genetic defect could be treated and even cured before it is born. that it
would be playing God. spiritual. and ethical perspectives. Over the past ten years. or even
performing genetic surgery. reproductive technology. Eventually the hope is to completely
eliminate certain genetic diseases as well as treat nongenetic diseases with an appropriate
gene therapy. many pregnant women elect to have their fetuses screened for genetic
defects. Gene therapy is the medical treatment of a disease by repairing or replacing
defective genes or introducing therapeutic genes to fight the disease.What are the benefits of
human genetic engineering The benefits of human genetic engineering can be found in the
headlines nearly every day. Currently on the market are bioengineered insulin which was
previously obtained from sheep or cows and human growth hormone which in the past was
obtained from cadavers as well as bioengineered hormones and blood clotting factors. ALS
Lou Gehrigs disease. These new pharmaceuticals are created through cloning certain genes.
through genetic engineering. The results of these screenings can allow the parents and their
physician to prepare for the arrival of a child who may have special needs before. The field of
human genetic engineering is growing and changing at a tremendous pace. that everybody
has a . Another benefit of genetic engineering is the creation pharmaceutical products that
are superior to their predecessors. Currently. scientists all over the world are aggressively
researching the many different facets of human genetic engineering. The most promising
benefit of human genetic engineering is gene therapy. The potential power of human genetic
engineering comes with great responsibility. World Transhumanist Association December
Slightly revised April and March Imagine that you are one of the human clones that will be
born there is little doubt that this will happen sooner or later. legal. With these changes come
several benefits and risks. You hear people opining that cloning threatens human dignity.
One possible future benefit of human genetic engineering is that. a cure can be found for
these diseases by either inserting a corrected gene. modifying the defective gene. with gene
therapy. and countless other fields. And imagine yourself listening in to the current
arguments for making cloning illegal. and cystic fibrosis are caused by a defective gene.
pharmacology. such as Huntingtons disease. With the successful cloning of mammals and
the completion of the Human Genome Project. The hope in the future is to be able to create
plants or fruits that contain a certain drug by manipulating their genes in the laboratory. and
after delivery. Many diseases. Oxford University Chair. certain autoimmune diseases and
heart disease have been treated with gene therapy. Human Reproductive Cloning from the
Perspective of the Future Nick Bostrom Faculty of Philosophy. These continuing
breakthroughs have allowed science to more deeply understand DNA and its role in
medicine.
suppose you were a slightly deformed human clone . and so forth. not realizing that personal
identity is not reducible to genetic identity.a unique human person. By the time the first
human clone becomes an adult. with just as much human dignity as those of us who were
conceived in more traditional ways.would you agree that it was a terrible moral offense to
have caused you to come into existence Historically. How yucky to take a living heart out of
one person and put it in the chest of another And such was the case with in vitro fertilization.
In the big scheme of things. Such was also the case with heart transplantations. The
argument that we ought to postpone human cloning until we have perfected the method in
animals makes some degree of sense. People argued that it was unnatural and that it would
weaken our moral fiber. the people who choose this option will be in a tiny minority. There is
one argument that. cloning will not significantly change the world. the moral debates over
cloning will probably be long forgotten. was in its own time condemned by bioconservative
moralists. heart transplantation is seen as one of medicines glories. Some people may
choose to have a child that is a clone of a stranger they admire. we should be wary of
viewing it as embodying a great quotWisdom of Repugnancequot. Some people will owe
their lives to this technology. Even so. pace Leon Kass. Such was the case with anesthesia
during surgery and childbirth. we find that many a great medical breakthrough. and. Some
people may misguidedly use cloning to try to bring back a lost child or a loved one. yet if the
current level of demand for elite sperm or elite eggs is any guide. We all have a moral
responsibility to recognize the clone for what she is . We are prone to prejudice and to
narrowminded underestimatation of the longterm benefits of technological development.
perhaps a great scientist. of course. now rightly seen as a blessing. and some infertile
couples will be grateful for having had the chance to raise a child of their own. I think we can
learn something from these historical episodes. How would it make you feel To hear all these
dignified people talking about you as if your very existence were a crime against humanity
Such an imaginary pointofview can help us put things in perspective. The quotyuck
factorquot needs to be treated with a great deal of skepticism. Today.right to a unique
genome except identical twins or to an unknown genome. anesthesia is taken for granted. .
especially for the purposes of making public policy. These quottest tube babiesquot would be
dehumanized and would be suffer grave psychological harm. The present opponents of
cloning may have retired or moved on to being outraged about other things. you might
understand and agree with concerns about the safety of the procedure. as a future clone.
and the public approval rate of IVF is up from in the early seventies to over today. The clone
will hopefully be descibed in more welcoming language than that used by many current
commentators. athlete or religious leader. One lesson is that our immediate emotional
reactions to medical developments are an unreliable indicator of their morality.
This doesnt mean that we should subordinate ourselves to some grand technological
imperative. and in the future few would wish to return to the present day. Or we can stand by
the sidelines and passively watch the future unfold. learned to use fire. that we should not
automatically reject opportunities for growth merely because they would change our current
human nature in some way. One day we will find ways of halting and reversing human
senecence. leading to developments that will overshadow cloning. however. Or . Those
prospects deserve our serious attention and concern. or even you and I if we manage to stay
alive until then. use and oversight of transgenesis for the purposes of food animal production.
We have a choice. We should strive to be humane rather than just human. Few of us would
want to go back to that stage. physical. and the beginning of what one might call a
quottranshumanquot era. emotional.genetically engineered biowarfare agents. . and physical
capacities. cognitive. We will have the option of extending our intellectual.and this is I think is
the best alternative .in fact. Some of these developments will be truly frightening . This will be
the end of humanitys childhood. . Other developments will open up unprecedented
opportunities for human growth and flourishing. for example. The Consultation also
discussed future perspectives on development. and took up agriculture. and new weapons
based on molecular nanotechnology. the Consultation considered the potential hazards of
transgene expression on the animal and on human healthrelated environmental issues. It
does mean. anticipated applications and possible outcomes from transgene integration and
expression. and spiritual capacities beyond the levels that are possible today. will look back
on today and todays primitive condition in much the way we now look back on our humanoid
ancestors before they developed language. more so. Introduction A safety assessment of
foods derived from GM animals must be grounded in an understanding of transgenesis
methods. State of the art in GM animal production .we can actively participate in creating a
future that will eventually enable us all to reach nearly unimaginable levels of human
flourishing and wellbeing through the use of advanced technology to defeat disease and
aging and to increase our human emotional. Against this background. Our descendants. We
can work against the transhumanizing developments and join the reactionary forces that
decry each new technological breakthrough that changes human nature.Meanwhile. other
areas of technology will be advancing fast and furiously. Ethical sensibility and a broad
conception of human flourishing is as important than ever .
Although issues posed by genetically modified insects need discussion.a DNA element
capable of excising itself from one location in the genome and inserting itself into another
location. Techniques A number of techniques can be utilized for transferring genes into
animals Houdebine.The Consultation also noted that genetically modified insects are being
produced.genes may be introduced into oocytes or spermatocytes. .coating the expression
vector on to gold particles. nuclei from successfully transformed cells can be transferred into
enucleated eggs and implanted into surrogate dams to generate somatic cell cloned animals.
and that has been modified to contain the fusion gene.g. followed by cloning . which has
been modified to contain the fusion gene. by application of antibiotics.. generating a whole
animal. Some marker genes are simply reporters for successful gene transfer. The use of
different types of expression vectors poses methodological advantages for different classes
of animals. Common methods for introducing an expression vector into the host include y y y
y y Microinjection . Transformation of gametes .a virus that can integrate itself into the
genome and become expressed through the host cells replicative processes.introduction of
the expression vector into fertilized eggs or host cells by application of pulses of electricity to
induce transient pores in the membrane of host cells. which are also transgenic. while others
encode gene products so that transgenic individuals can be selected for. Biotechnologists
may purposely transfer into a host a y y y Fusion gene .a gene encoding a product of interest
with an element that will regulate its expression in the host. Transposon . Particle
bombardment . they were beyond the scope of this Expert Consultation. and introduction in
host cells by bombardment with the particles. They differ in their suitability for different
classes of animals. Retrovirus . Electroporation . although not currently for food
production.since it is more straightforward to add or knock out genes for cultured cells than
for fertilized eggs. . Cell transformation. Techniques and applications . and in their
implications for risk assessment. The gene to be transferred is incorporated into an
expression vector that also contains genetic elements to control its expression.direct injection
of the expression vector into fertilized eggs or host cells using a fine glass needle. and also
affects the likelihood of subsequent genetic or immunological hazards being realized. . e.
Many expression vectors contain marker genes. and the transformed gametes used for
fertilization. in their efficiency of transformation. Utilization of the gene transfer approach
depends upon knowledge of a gene encoding a product conferring a trait of interest.
nuclei from transformed cultured cells or transformed cells from a mosaic animal can be
used as donor material for somatic cell nuclear transfermediated cloning. posing a range of
possible benefits to food production or human health Table . Transgenics Introduction of a
transgene into an animal is not a precisely controlled process. Insertion of a transgene
sometimes can affect expression of another genes. Applications and their potential benefits
Transgenic animals expressing one introduced gene have been or might be developed for a
variety of applications. producing individuals that are transgenic in all cells. sometimes
affecting the viability or health of the host. Such animals are at various stages of
development. and can result in a variety of outcomes regarding integration. thereby
becoming nonfunctional.e. as is already being applied for development of pigs intended for
xenotransplantation. they have it in some. . However.. Foodrelated hazards associated with
producing GM animals The discussion below addresses hazards associated with
transgenesis methods and the environmental release of GM animals that have a bearing on
food safety. The possible hazards of transgenesis discussed below must be placed into
perspective by considering their relative likelihood and the degree of harm they pose. i. but
not all.. especially because of their low reproductive rate and internal fertilization and
development. We note that these hazards are not unique to transgenesis.Application of any
one of these methods will result in the successful transformation of a small percentage of the
animals so produced. A transgene may become rearranged before integration. Early
applications for approval of transgenic animals for food production involve several species of
fishes expressing introduced growth hormone genes. . . including integration of multiple
copies of the transgene at one locus or insertion of the transgene at multiple locations in the
genome. For these reasons. of their cells. undesired DNA sequences may become inserted
into the genome. other outcomes are frequently observed. and not in a functional gene or a
regulatory element. Many transgenic founder individuals are mosaic for the transgene.
Production of transgenic agricultural mammals is challenging and expensive. . expression
and stability of the transgene in the host. This approach might eventually be used to produce
transgenic lines for food production. Transgenic individuals can then be identified and bred to
develop a transgenic line. Insertion of the transgene into a host gene may turn the host gene
off. During the process of transgenesis. where several transgenes will have to be expressed
and several host genes knocked out. development of transgenic agricultural mammals has
lagged. The desired outcome generally is stable integration of a single copy of the transgene
into a single location in the genome. However.
Other outcomes. The transgene can be silenced by methylation or through other
mechanisms. Work with Drosophila suggests that transposons may have a greater
probability of movement following crossing into a new background strain. that is. sheep and
fish exhibiting a range of morphological or metabolic abnormalities.. Hazards stemming from
insertional events or genetic instability can be identified by screening and managed by culling
individuals that have undesired events during the course of development of the transgenic
line. Other pleiotropies. have been observed. sexes or life stages where it is not expected.
and could also give rise to a new evolutionary pathway for adaptation of pig viruses to
humans. Expression of the transgene ideally should have no undesired effects on the
expression of other host genes or health of the host. Ectopic expression of the transgene
may occur in tissues. and have included pigs. The development of pigs for
xenotransplantation involves knocking out expression of molecules that elicit immune
response in humans and adding molecules that make the surface of pig cells more like that
of human cells. . Because expression of the transgene often is controlled by novel regulatory
elements outside the hosts normal homeostatic feedback mechanisms. expression of the
transgene can have pleiotropic effects. effects upon multiple traits of the host. This results in
some degree of altered gene expression. did not address the risks associated with cloning
per se especially somatic cell nuclear transfer. Even though the vectors were engineered to
lack all the DNA sequences needed to be packaged into virions or to transpose. Hazards
stemming from transgene expression can be identified by screening and managed by culling
individuals with undesired expression phenotypes during the course of development of the
transgenic line. and may affect the health of the host and the safety of its food products.
Notable pleiotropies have been observed among animals expressing introduced growth
hormone genes.such as marker genes or selectable markers from the expression vector or
contaminating bacterial DNA left over from vector production. may be positive. This raises
the possibility that pigs might become more susceptible to human viruses. Cloning Cloning
may be used to propagate GM animals and raises its own issues. however. thereby gaining
infectivity or mobility. The effects of altered gene expression and of reproductive
manipulations needed for the cloning process may result in high . Somatic cell nuclear
transfermediated cloning requires reprogramming of the genome from a differentiated cell to
allow it to drive embryogenesis. Development and use of welldesigned vectors will reduce
the likelihood of these hazards. however. The use of viral and transposon vectors poses the
hazard that the transgene might subsequently move within the genome. or with exogenous
viruses or transposons. The Consultation. especially early in the life of the cloned individual.
such as endogenous transposable elements. This could provide an alternative host for
spread of human disease. such as increased carcass yield. there is a theoretical possibility
that they could recombine with other DNA sequences in the genome. This hazard could
theoretically be minimized by using pig breeds lacking known endoviruses for development
of xenotransplantation lines and by maintaining such lines in strict quarantine.
transgenic line and local environmental conditions. posing additional routes for accidental
entry into the environment. dog. cat. mobility and historical reports of ecological community
disruption Such a ranking from high to low for North America National Research Council. .
focuses on the connection between environmental entry of GM animals and food safety.
Observation of the limited numbers of offspring of cloned animals produced to date suggests
that they may be phenotypically normal. pig. The assessment should compare the GM
animal with its conventional counterpart. given the estimated rate of escape. would consist of
insects. sheep and cattle. The potential entry of GM animals into the food supply via the
environment will vary owing to different predispositions of the animals to enter the
environment and spread. i. horse. the relevance of this ranking to food safety will change
depending upon whether these animals are widely eaten by humans. fish. chicken. has a
lower. but the same risk factors apply. . could be harvested without being detected and
subsequently eaten by people. purging would be a safer . rabbit. This discussion does not
address all environmental issues but. Recent research suggests that the transgene could be
purged within a few generations or could spread through the natural population and possibly
affect its abundance Muir and Howard.rates of prenatal and postnatal mortality and of
morphological or physiological abnormalities in cloned individuals. equal or higher potential
for gene flow to any wild or feral relatives found in the receiving ecosystem. rather. and
somewhat later for some kinds of GM poultry such as ducks and quail. differences in the
farming systems ability to reduce animal escape. Furthermore. Pew Initiative on Food and
Biotechnology. . Scientists Working Group on Biosafety. . The current status of development
of GM animals suggests that food safety managers might be faced with this issue first for GM
fish and shellfish. likelihood of escape from captivity. Some farmed animals are often
transported and sold alive. .e. . micerats. Key species or taxa of GM animals can be ranked
in terms of their ability to become feral. shellfish.. goat. This involves assessing whether y the
GM animal. On a regional scale. Escaped GM fish and shellfish. . or their descendants. For
potential entry into the food supply. . The assessment should estimate the probability of
movement of the GM animal or its transgenes into the environment. The potential spread of
GM animals or their transgenes in the environment is an environmental hazard that provides
a route for entering into the human food supply. which may in turn affect animal health and
food safety National Research Council. Environmental considerations that can affect food
safety Different GM animals pose different potential environmental benefits and risks
National Research Council. Assessment of the potential environmental spread of GM
animals or their transgenes should be done casebycase for each combination of integration
event i. and differences in whether humans hunt or fish for the same species.e. the rankings
will vary among regions owing to different environmental conditions. unmodified animals
derived from the same genetic source. compared with the conventional counterpart.
. There is a need to validate this methods predictions. and entering the fitness data from step
into a simulation model that predicts the fate of the transgene across multiple generations.y
outcome. Status of methods for estimating potential environmental entry The best methods
for reliably characterizing potential environmental entry have not yet been standardized.. .
Biological. The primary focus of these measures should be to ensure that release does not
occur. i.g.. compared with the conventional counterpart. The netfitness methodology Muir
and Howard. . the GM animal. screens in effluent pipes of landbased fish tanks or ponds and
physical confinement involves making an aqueous escape pathway lethal by changing a
physical attribute of the water e. . . If this cannot be assured. However. Mechanical
confinement involves application of some kind of implement to prevent or reduce escape of
animals from the aquaculture system e. . Scientists Working Group on Biosafety. mechanical
and physical/chemical confinement measures are available for fish and shellfish produced in
different aquaculture systems Agricultural Biotechnology Research Advisory Committee. and
then cool down before discharge. their conventional counterparts or wild relatives. then it can
be complemented by the use of methods to ensure that any escaped individuals cannot
reproduce.reeusda. has a lower.e. Biological confinement measures typically involve
disrupting the animals ability to reproduce. heat effluent water to lethal temperature.
Kapuscinski.htm. For example. . resulting in individuals with three sets of chromosomes
rather than the normal two sets. . efforts to gather such data have recently begun for a few
cases of GM fishes.gov/crgam/biotechrisk/biotls. initial experiments are under way towards
this end. and crosses between the two. There is also a need to add stochasticity. Other
confinement systems could be developed for GM terrestrial animals. elaborate additional
features and improve the userfriendliness of the simulation model. such as sterilizing fish and
shellfish by induction of triploidy. then risk managers should consider the need to apply
confinement measures to prevent or reduce escape of GM animals or their viable gametes
into the environment. . . It involves a twostep process measuring fitnesscomponent traits
covering the entire life cycle for GM animals.. a transgenic fish project is testing the validity of
the netfitness models predictions summary at www. these animals may still enter the food
supply because the purging process is likely to take one or more generations. Pew Initiative
on Food and Biotechnology. The data needed to apply this methodology have yet to be
obtained for most GM animals. Confinement of GM animals If the combined conclusions from
the environmental hazard characterization discussed above and the food safety assessment
discussed in section are that GM animals or their transgenes will spread in the environment
to a degree that poses a risk to the human food supply.g. equal or higher potential to invade
and establish itself as an alien species. particularly when the receiving ecosystem lacks wild
or feral relatives. provides a systematic and comprehensive approach based on
contemporary evolutionary and population biology National Research Council.
it will be important to consider whether or not to apply postmarket monitoring for unexpected
environmental spread of the GM animals and their transgenes that pose food safety hazards.
There is a need to develop and validate better methods for reliably inducing reproductive
sterility of GM animals. For instance. such as honey bees. and also necessitate their
assessment with respect to food safety and environmental impacts e. In such situations. in
particular GM fish and shellfish. allfemale triploid populations of salmon can be used to
ensure that any individuals that might escape physical confinement are unable to reproduce
in the wild. Monitoring for environmental entry and spread In future.g. there is a need to
develop fully appropriate protocols for the application of these methods to postmarket
detection of environmental spread of GM animals and their transgenes.. . Transfer of new
genes and advances in gene transfer and cloning techniques will facilitate developments
contributing to human health by means of new animal models of human disease. there is a
need for multiple confinement measures because no single measure is fully effective. by
inserting antisense genes to disrupt key steps in the endocrine pathway controlling
reproductive development. gene silencing and epistatic and pleiotropic effects of transgenes.
Monitoring can also be helpful to assure confinement of GM animals during research and
development. risk management and risk communication. . These innovations may include
using improved expression vectors to target transgenes to specific places in the host
genome or incorporating transgenes on to bacterial or yeast artificial chromosomes and their
introduction into the host. However. Although many potential benefits from GM animals can
be anticipated. There is also a need for robust verification of confinement measures.
especially development of embryonic stem cells or primordial germ cells from additional
species. for instance. Future perspectives Realizing the full range of potential benefits from
use of GM animals will depend on advances in technical aspects of their production. insects
with food safety implications. . innovative molecular methods will be needed in order to
address current limitations with respect to low frequency and randomness of integration.. For
instance. expression of pharmaceutical proteins and development of genetic lines for
xenotransplantation. Methods for detection of such GM animals and their transgenes in the
environment are likely to involve the application of two wellestablished bodies of scientific
methodologies diagnostic. DNAbased markers and sampling protocols that are adequate in
terms of statistical power and costeffective. Improved methods could include repeatable
protocols for induction of triploidy applicable to animals other than birds and mammals and
new methods for inducing sterility via chemical treatments or gene transfer.In many cases.
either with or without approval to enter them in the human food supply. Greater experience
with antisense gene expression and homologous recombinationbased gene knockout
techniques will allow the turning off of targeted genes. will facilitate a greater range of genetic
modifications of those animal species. Other advances. specific GM animals may gain
approval for widespread production. Identification and the transfer of genes will promote
beneficial food uses. these will present more challenging conditions for risk assessment.
and Nile tilapia rate Improved disease resistance Lactoferrin gene in carp cecropin gene in
channel catfish Increased tolerance of Antifreeze protein in Atlantic Cold tolerance was
environmental conditions. salmon and goldfish improved in goldfish such as low temperature
but not in salmon Improved digestibility of feed ingredients Phytase gene in pig Approach
could also be used to adapt carnivorous fishes to a plantbased diet Improved Change in
nutritional product quality profiles Remove allergens from food Reduced lactose
concentration in milk Knock out gene for allergenic protein in shrimp Novel ornamental
animals Fluorescent protein genes expressed in zebrafish Novel products Pharmaceuticals
for human Genes for monoclonal and veterinary use antibodies. lysozyme. growth hormone.
Examples of application of gene transfer to animals Application Improved animal production
Intended outcome Example Comments Increased yield by Growth hormone gene in
accelerated growth rate or Atlantic salmon. etc. tissues and organs for xenotransplantation
Animal health Prevention of transmissible Knock out Prnp gene of spongiform cattle and
sheep encephalopathies Biocontrol Pesticideresistant beneficial insects Introduction of
pesticide Ability to use both resistance gene into predators chemical and and parasitoids
biological means of .TABLE .. expressed in milk or blood of farm animals Industrial products
Bioindicators Sensors for pollution Spider silk expressed in milk of goats Expression of
reporter genes linked to metallothionein promoter in topminnows exposed to heavy metal
ions Knock out of galactosyl transferase gene in pig Cloning may also be needed Prevention
of mad cow disease and scrapie Human health Cells. common improved feed conversion
carp. insulin.
failure rate. Many people see cloning as a way to provide children for those couples who
cannot have them naturally. if scientists clone these exceptional cows. However. However.
cloning is the best option. Because natural breeding can lead to the decay of the new/altered
gene. While there is always someone willing and able to pay the price. there are some
practical applications currently being considered. special cows that can make up to . is the
cloning of humans morally right . Mad scientists with armies of cloned zombies are highly
improbable due to the current cost. gallons a year. But what can we do with it Very few see a
future society of cloned humans. and time involved. if the new/altered gene is damaged.
Farming The average dairy cow puts out roughly . there are certain. Which are possible and
which are doomed to remain in the realm of science fiction Only the future will tell. In
fact.insect pest control Control transmission of disease Reproductive and sex control
Introduce genes for resistance Could reduce to Plasmodium parasite to transmission of
Anopheles mosquito malaria Introduce antisense gene for Could be used to GnRH or
aromatase control invasive exotic species Cloning is truly a monumental accomplishment.
mammalian cloning was only pursued as a step toward copying genetically altered cells. the
animal carrying the damaged gene will not be as useful to the scientists. it is also unlikely
that it will never be attempted. Scientists have to be very careful about protecting the altered
portion of the genome. Infertility Treatment While it is unlikely that the cloning of humans will
ever become standard practice. Most Prevalent Application What many scientists forsee as
the most probable and widespread application of cloning is the mass production of
genetically engineered animals. Selectively breeding for this trait is nearly impossible given
the complexity of the genetics governing milk production. However. the profit gained from
increased milk outweighs the money spent on a cloned cow. because the original DNA is
used over and over to make new animals. gallons of milk a year.
These biological products have prime importance in medical utility.C. However. . they should
be able to grow those cells into a working. On July . If scientists can find a way to force cells
to differentiate to become a failing organ. once the worlds largest bird. all attempts to make
her pregnant using the frozen sperm have failed. high milk or crop production etc. Lady was
cloned. . Applications Gene cloning has various applications in different realms of biology.
Therefore.Jurassic Park Scientists have told us that it would be virtually impossible to find an
intact cell from a extinct dinosaur. many people die. Gene cloning provides a feasible method
to produce bulk of these products. Protein synthesis is a major field where gene cloning has
found its application. Each year. Crop improvement and boost in food production are the two
main objectives of cloning. Research was stopped by the Ngai Tahu Maori tribe. Because the
new organ would be an exact match for the patient. Some of the major applications are
discussed below. because it is a liquid organ and has no shape.. which claims to own the
DNA because they were sole owners of the land when the bird became extinct around .
Many predict that the first organ to be cloned in this way may be bone marrow. The scientists
were then going to breed the new moa with an ostrich or an emu to create a new giant bird.
is the hope of preserving the nearlyextinct Enderby Island cows. there would be no need for
antirejection drugs. Gene cloning is used for synthesizing many therapeutic and
pharmaceutical proteins like insulin. In . Gene cloning has played a remarkable role in
agriculture. Because Lady is so old. Crop improvement can be done both by introducing a
useful gene in crops like nitrogen fixing genes are transferred to some major crops. interferon
and hormones. Elsie L. Several genes in plants as well cattle are manipulated to develop
various qualities pest resistance. Organs for Transplant Another option open to the future is
the cloning of specific organs for transplant. a herd of cows that was damaging the ecological
balance of New Zealands Enderby Island was almost completely destroyed. adult organ. It
can also be done be suppressing the expression of some undesirable genes like blocking the
genes responsible for ageing. those who do find donors many times have to take
antirejection drugs for the rest of their lives. All that remained was the frozen sperm of ten
bulls. unable to find a suitable organ donor. it is conceivable that solid organs would be able
to be cloned outside a body as well. and one living female. Lady. However. at New Zealands
University of Otago. Ladys Clone was delivered by Casarean section. The expression of
these proteins in large quantity via the cloning plays an important role biotechnological
development. scientists are trying to clone the extinct moa. In addition. . The plan was to take
DNA from its leg bone and implant it into a chicken egg to grow. Cloning of stem cells will
provide treatment to various diseases.
atbiotechbook. Hence it acts as a store house of genetic material.com/.htm http//www. This
technique is also used for creating gene library. agricultural and industrial applications but
there are certain disadvantages like loss of gene
diversity.jrank.org/pages//CloningGenes.com/GeneCloning. It is also a major topic of ethical
debate.php . it is possible to identify any specific gene and whenever required any desirable
gene can be multiplied by growing in relevant host.html
http//medicine.fao.com/views/cloning.html http//www. If gene diversity is lost due to
excessive cloning.naturalnews.. there are no mutations to allow some of the cloned group to
survive a newly introduced disease. The gene library contains multiple copies of genes/
genomes.html http//www. http//www. Conclusion Gene cloning has various
medical.nickbostrom.org/DOCREP//YE/ye. It is a boon or curse will remain a question in
recent future. As every coin has two faces so does this technology have.