GloFish: The first pet available to the public, the GloFish is a Zebrafish crossed with a jellyfish.http://www.transgenicanimals.info/examples-of-transgenic-animals/
CHAPTER 5: TRANSGENIC PREPARED BY: SITI RAIHANAH BT SABRI ( SB09014) GAN SIEW MEI (SB09025) SITI HAJAR BT MOHD RASDI (SB09060) NOR ATIKAH BT MAHMOOD (SB09039) NOOR AFIFAH BT FAUZI (SB09059)SHORIYA ARUNI BT ABDUL MANAF (SB09042)
DEFINITIONTransgenic organism is defined as living organisms containing genetic material into which DNA from a different organism has been artificially introduced. (Oxford English Dictionary, 11th edition)
HISTORY Was first created in 1973 by Stanley N. Cohen and Herbert Boyer. Demonstrating the creation of a functional organism that combined and replicated genetic information from different species. The first transgenic animals were mice created by Rudolf Jaenisch in 1974.He managed to insert foreign DNA into the early-stage mouse embryos the resulting mice carried the modified gene in all their tissues. Subsequent experiments, injecting leukemia genes to early mouse embryos using a retrovirus vector, proved the genes integrated not only to the mice themselves, but also to their progeny.
DEFINITION A transgenic microorganisms is a microbe, usually a bacterium, into which genetic information has been introduced from the outside and which possesses the ability to pass that information on to subsequent generations in a stable manner.
Recombinant DNA TechnologySteps:1. Bacterial plasmid is spliced using the restriction enzyme EcoRI and the desired foreign genetic material is cut by the same restriction enzyme2. The cut pieces of DNA are called "sticky ends" because the unpaired base pairs allow them to combine and stick together3. With hybridization and an enzyme, DNA ligase, the two pieces of DNA are combined4. The new plasmid is put into the bacterial cell and now it will produce the protein that the foreign genetic material coded for
Importance:(1) Involve in the production of medicine/food products.Microbes: Escherichia coli, Lactococcus lactis A company called Genentech was among the earliest and most successful commercial enterprises to use genetically engineered bacteria to produce human proteins. Their first product was human insulin produced by genetically engineered Escherichia coli. The drug industry has made good use of this discovery in its production of medication for diseases such as diabetes and haemophilia.
A variety of other human hormones, blood proteins, and immune modulators are now produced in a similar fashion, in addition to vaccines for such infectious agents as hepatitis B virus and measles.• The sweetener in most diet sodas- phenylalanine is made by transgenic bacteria.
Importance:(2) Plays an important role in environmental cleanup, or bioremediation.Microbes: Escherichia coli, Pseudomonas fluorescens, Burkholderia cepacia Scientists have discovered many naturally occurring genes that code for enzymes that degrade toxic wastes and wastewater pollutants in bacteria. Examples: genes for degrading chlorinated pesticides, chlorobenzenes, naphthalene, toluene, anilines, and various hydrocarbons.
Dr. Gordon Hill, a chemical engineer at the University of Saskatchewan created a biofilm reactor that successfully removes pollutants from oil industry waste water. 1. Oil-eating bacteria is grown in the reactor tube until thick film created in the tube. 2. Waste water is pumped into the top of the reactor tube where gravity pulls it down and through the biofilm while air is pumped in from the bottom to induce the bacterias digestion. 3. The thoroughly cleaned water comes out of the tube • However, scientists have not yet discovered what genes are responsible for the conversion of oil into harmless byproducts. • If this happen, they can harvest the protein or enzyme and this will be much less costly than the current biological methods. Courtesy of: The AgBiotech Infosource
Importance:(3) Used in some soils to facilitate crop growth.Microbes:Pseudomonas putida. In 2011, a research has been done using genetically modified bacteria which shown positive result by successfully suppressed the damping- off of cucumber seedlings infected with the plant-pathogenic fungus Rhizoctonia solani. It is an alternative to reduce application of agricultural chemicals for sustainable agriculture.
Other than directly used, transgenic microorganisms can also act as vectors for transgenic animal and plants. The vectors will be inserted into target organisms to express the interested gene .
DEFINITION Transgenic animals are the genetically modified organisms which have a foreign gene in their genome due to which they show certain properties which are different from non genetically modified organisms. Glow-fish as pets Sheep with more wool Cow producing more milk with lower cholesterol Goat producing silk
METHOD Transgenic animals can be produced by using three basic methods which are: DNA microinjection Retrovirus-mediated gene transfer Embryonic stem cell-mediated gene transfer
DNA Microinjection The mouse was the first animal to undergo successful gene transfer using DNA microinjection. This method involves: Transfer of a desired gene construct from another member in the same or different species into the pronucleus of a reproductive cell. Then, it will be cultured in vitro until reaches embryonic phase, then transferred to the recipient female.
Embryonic Stem Cell-Mediated Gene Transfer This method involves: Isolation of totipotent stem cells (stem cells that can develop into any type of specialized cell) from embryos. The desired gene is inserted into these cells. Cells containing the desired DNA are incorporated into the host’s embryo, resulting in a chimeric animal.
Retrovirus-Mediated Gene Transfer A retrovirus is a virus that carries its genetic material in the form of RNA rather than DNA. This method involves: Retroviruses used as vectors to transfer genetic material into the host cell, resulting in a chimera, an organism consisting of tissues or parts of diverse genetic constitution. Chimeras are inbred for as many as 20 generations until homozygous (carrying the desired transgene in every cell) transgenic offspring are born.
IMPORTANCE AgriculturalMedical Industrial Have the potential to improve human welfare in:
MEDICALGene therapy• Process in which healthy genes are inserted in the person’s body in place of defected genes that might cause diseases.• Scientists of Finland have developed a calf which carries a gene that responsible for making a substance which promotes the growth of red blood cells in humans.Pharmaceuticals• Production of insulin, growth hormones and blood clotting factors in the transgenic animals.• These are obtained from cow, goats or sheep’s milk through transgenesis to treat the diseases like cystic fibrosis and phenylketonuria.
Xenotransplantation• A surgical procedure in which tissue or whole organs are transfered from one species to another species.• Scientist successfully done experiments in pigs and developed human organ. But there is a protein in pig which cannot be accepted by human immune system.• Now they are working on this problem and trying to replace this protein with the human protein that can easily accepted by the human immune system.
AGRICULTURAL • Farmers breed the animals selectively to obtained healthy animals that have the required traits for example, increased amount of milk and healthy meat.Breeding • Beneficial for farmers to get the higher yield in short time. • Diseases like influenza can cause damage to the animal body, so that the genes that show resistant against this disease was inserted into animal body. Disease • To avoid the disease spreads from one animal to the other.resistance • Transgenic cows are able to produce milk which has more nutritional value than an ordinary cow’s milk. Quality
INDUSTRIALTwo scientists of Canada have successfully inserted spider genes into goats which arelactating.Along the milk production, goats will also produce silk which is a light flexiblematerial used to make tennis rackets, medicine micro sutures and army uniforms.For the safety of chemicals, scientist have produced toxicity sensitive transgenicanimals.Many proteins have produced by using transgenic animals which in turn convert intoenzymes to perform different functions in the body.
DEFINITION Plants that have been genetically engineered, a breeding approach that uses recombinant DNA techniques to create plants with new characteristics. Can be transformed using 2 approaches: Agrobacterium tumefaciens Gene gun/Biolistic bombardment system
1. Agrobacterium tumefaciens Causal agent of crown gall disease During the infection, a specific segment of the Ti plasmid DNA is transferred from the bacteria to the plant. Scientists have exploited this genetic transfer in order to get genes with desired properties into plant cells.
2. Gene gun/Biolistic bombardment system Desired DNA is coated on microcopic gold or tungsten beads The particles are fired by a gun into plant tissue and penetrate the cell wall DNA unwinds from gold carrier particle and enters the nucleus
BENEFITS1. Improved shelf lifeExample: GMO tomato- Partial inactivation of the polygalacturonase gene increase the time between flavor development and spoilage of the fruit- Delays ripening of fruit and vegetables thus allowing an increased length of storage- Increased flexibility in production and harvest
2. Improved nutritionExample: golden rice (oryza sativa rice)- Designed to produce beta- carotene, a precursor of vitamin A in the rice endosperm by transforming rice with 2 beta-carotene biosynthesis genes.- Reduce blindness and prevent malnutrition worldwide- In august 2012, tufts university published new research on golden rice showing that beta carotene produced by golden rice is as good as beta carotene in oil at providing vitamin A to children.
3. Herbicide resistanceExample: roundup canola- modified using gene technology to tolerate glyphosate by inhibiting the production of EPSPS (5-enolpyruvylshikimate-3-phosphate synthase), an enzyme necessary for the production of amino acids and essential for plant protein production and growth.- New genetic trait enables the canola to produce two enzymes – one which protects it from the glyphosate and another which degrades the glyphosate.- protein cannot be made and the plant system of the target weed collapses
4. Pathogen resistance (viruses)Example: transgenic PRSV-resistant papaya Contain a virus gene that encodes for the production of the coat protein of the virus The coat protein’s primary function is to protect viral genetic information Expression of this gene renders the papaya resistant to the virus. Aphids spread PRSV by feeding off infected and then uninfected plants
5. Pesticide resistance Example:Bt corn- Genetically altered to express bacterial Bt toxin, which is poisonous to insect pests ( European corn borer)- Expressing the toxin was achieved by inserting a gene from the microorganism Bacillus thuringiensis into the corn genome- This gene caused formation of pores in the Lepidoptera larval digestive tract and allow enteric bacteria to enter the hemocoel, where they multiply and cause sepsis.
Political and Legal aspects on biosafety United Nations Envrionmental Programme—GlobalEnvironmental Facility (UNEPGEF) makes efforts in the national biosafety framework project with majority of developing countries, but the synergy efforts with the international organizations specialized in the biotechnology and biosafety are undervalued and underutilized.
Examples : The International Center For Genetic Engineering And Biotechnology (ICGEB) Consultative Group On International Agricultural Research (CGIAR) Have quite strong relationships with the developing countries needing the supports and a long-term assistance for well-identified partners in developing countries and other stakeholders
Evolving regulation for sustainable development ( example : biosafety regulation) Genetically Modified Organisms ( Contained Use) Regulations 2000 (GMO (CU)) o Provide for human health and environmental protection from GM microorganisms and also GM plants and animals Other legislations : o Section 108 (1) of the Environment Protection Act 1990 o The Genetically Modified Organisms ( Risk assessment) (Records and Exemptions) Regulations 1996 o The Gentically Modified Organism (Deliberate Release and Risk Assessment-Amendment) Regulations 1997
Organizing mechanisms :1. Risk/benefit analysis Evaluating benefits Evaluating risk Research and sources information2. Risk management Impact assessement processes Public awareness Design of regulatory system
ECONOMY EFFECTS PROS Improved crop productivity in poor area Able to boost agricultural production Insect-resistant and herbicide-tolerant able to lower the risk of crop losses Potential to produce medicines inexpensively Transgenic plants offer the modest cost for pharmaceuticals. Example: transgenic bacteria produce most of the insulin to treat the diabetics in the United States.
Cons Poor farmers might depend only on international corporations for seedsExample :Some transgenic crops are designed with terminatortechnology. So may have two negative impacts:1. Environmental2. Economic aspects
First, pollen from the plants could invade neighboring fields that cause other plants seeds become infertile. Second, farmers could become dependent on buying seed every year that require high costs.
SOCIO-ECONOMY EFFECTS Threat to food security Threat to livelihood Worsening debt trap and socio-political tension
Threat to food security Weaken any food security policies and practices that may be in place in many developing countries Genetically modified crops require high cost, so might squeeze the small and medium farmers out of business
Threat to livelihood Some companies producing substitute for tropical plants for substance normally derived from it such as vanilla, vegetable oil, chocolate and sugar Example:The livelihood of about 10 million sugar farmers throughout the South being threatened by genetically engineered sugars and sweeteners being grown and processed in the North.This would threaten export earnings of the countries in the South.
Worsening debt trap and socio-politicaltension New technologies are often accompanied with new credit package.Example : The Green Revolution could be implemented only with a credit package to buy high yielding varieties of seeds, chemical inputs and mechanical services. A large number of small farmers who took loans when the Green revolution was introduced could not repay back the loan had to forfeit their land by richer farmers thus causing social tensions.
Animal welfare Animal such as mice and pigs need to be genetically modify and bred to produce animal for biomedical research. Gives rise to many animal welfare problems, examples:1. Oocyte extraction from donor animals is usually surgical – stressed of recovery.2. Pregnancy in surrogates mothers is prolonged and heavy – painful birth.
3. Abnormal fetal development and late pregnancy mortality.4. Health problem during life, due to respiratory problem and immune system deficiency.5. Wasteful of animal life: Continuous breeding needed simply to maintain the transgenic line. Transgenic animal produced may not suitable for research and further breeding
Solutions1. Find a treatment for condition produced.2. Restriction of gene expression to tissue of interest or to certain time period.3. Establishment of endpoint for removing animal from a study before problem appear.4. Use embryo or sperm cryopreservation to maintain transgenic line that may not being actively studied.5. Develop a guideline to ensure transgenic animal are used ethically.
Religion views In US, a majority of Christian and Muslim say they are opposed to move genes from one species or organism to put into another. They believe the fate of humankind is in God’s hand and meddling with nature is sinful and goes against the wish of God. Other religions such as Buddhism and Hinduism do permit genetic engineering on animal if is it done with divine intent but not for selfishness and power. In animal biotechnology, if the intentions are good and the consequences are needed and beneficial, then maybe it is justifiable. So they accept genetic engineering on animal without suffering them.
Food safety concerns Labelling The labelling of the GMOs food products should be applied so that the consumers knows. Use of antibiotic resistance genes Allergenicity and toxicity Introduced genes may toxic itself and may also lead to production of toxin in products
CONCLUSIONTransgenic organism can be conclude as an organism whose genetic characteristics have been altered using the techniques of genetic engineering. Scientists today have the ability to modify the genetic makeup of plants and animals, and even to transfer genes from one species to another. Although it give many benefits, the transgenic organisms might give the problems and effects that are yet unknown.