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What are Genetically modified organisms (GMOs)What are Genetically modified organisms (GMOs)

GMO is defined as an organism in which genetic matter is altered in

a way that does’nt occur naturally. This technology is called

“Genetic engineering or recombinant DNA technology”Genetic engineering or recombinant DNA technology .

Most GM plants are generated by the biolistic method (particle gun)

or by Agrobacterium tumefaciens mediated transformation.

Such method are used to create GM plants-which are then used to

grow GM food crops.grow GM food crops.

These techniques are much more precise than

mutagenesis (mutation breeding) where an organism is exposed to

radiation or chemicals to create a non-specific but stable change.

GM CROPS DISTRIBUTION WORLD WIDEGM CROPS DISTRIBUTION WORLD WIDE

GM crops have been grown commercially since 1996. Sincethen the GM market has grown 74 folds and spread to 25countries. The global value of the GM crop market was 7.5billion dollars in 2008.

90% of GM crops, and almost all GM food crops, are grown infour countries—the United States, Argentina, Brazil, andCanada. The U.S. produces almost half of all GM crops.

The top three GM crops in 2010 were soyabeans (53 percentof total GM area), maize (30 percent), and cotton (15 percent).Others include rapeseed (canola), alfalfa, and papaya.

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WHY GM FOODS ARE PRODUCED:WHY GM FOODS ARE PRODUCED:

GM foods are developed – and marketed – because there is

some perceived advantage either to the producer or

consumer of these foods.

This is meant to translate into a product with a lower price,

greater benefit (in terms of durability or nutritional value)

or both with resistance against plant diseases caused by

insects or viruses or through increased tolerance towards

herbicides.

Common GM crops:1. GM soyabeans2.GM corn3. Bt Cotton4.Canola Others are GM tomatoes, potatoes, papayas,chicory melons rice squash sugar beets and wheatchicory, melons, rice, squash, sugar beets, and wheat.

Agricultural benefits1. Herbicide tolerance2.Protection against insect damage3.Virus resistance4.Tolerance to salty soily5.Drought toleranceHuman Health Benefits1.Reduction of mycotoxin contamination2.Lowered food costs potentially leading to more varied diets3.Nutrient enhancement4.Vaccine production

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How GM food/crop is produced?How GM food/crop is produced?GM crops are produced using laboratory techniques where

genetic material from the cells of one species is transferred

i h i ifi i ll li iinto another species to artificially create new living

organisms that would never naturally occur through

breeding.

Method-''Genetic modification involves the insertion or

deletion of genes. It involves majorly three mechanisms:

1. Conventional breeding (previously used)

2. Cisgenesis

3.Transgenesis

In conventional breeding multiple backcrosses must bemust be performed, each taking at least several months, to create a new cultivar.

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• In the process of cis genesis , genes are artificially transferred between organisms that could be conventionally bred.conventionally bred.• Cis genesis differs from conventional breeding because it can potentially create new varieties of crops more quickly and ycheaply and only selected beneficial genes are transferred and not other genes nearby on the chromosome.

• Transgenesis is the process of introducing an exogenous gene –called a transgene – into a living organism so that the organism will exhibit a new property and transmit that property to its p p yoffspring.• Transgenesis can be facilitated by liposomes, plasmid vectors, viral vectors, pronuclear injection, protoplast fusion, and ballistic DNA injection.•Transgenic organisms are ableTransgenic organisms are able to express foreign genes because the genetic code is similar for all organisms. This means that a specific DNA sequence will code for the same protein in all organisms.

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GM organism produced when exogeneous DNA penetrates the cell GM organism produced when exogeneous DNA penetrates the cell

membrane for any reason. membrane for any reason.

To do this artificially may require transferring genes as part of an To do this artificially may require transferring genes as part of an To do this artificially may require transferring genes as part of an To do this artificially may require transferring genes as part of an

attenuated virus genome or physically inserting the foreign DNA attenuated virus genome or physically inserting the foreign DNA

into the nucleus of the intended host using a microsyringe, or as a into the nucleus of the intended host using a microsyringe, or as a

coating on gold nanoparticles fired from a gene gun. coating on gold nanoparticles fired from a gene gun.

However, other methods exploit natural forms of gene transfer, such However, other methods exploit natural forms of gene transfer, such

as the ability of as the ability of AgrobacteriumAgrobacterium to transfer genetic material to plants, to transfer genetic material to plants,

etc.etc.

Specific examples of GM cropsSpecific examples of GM crops

The first commercially grown GM whole food crop was a

tomato (called FlavrSavr), which was modified to ripen without

softening.

• GM tomatoes can remain fresh longer they can be allowed to ripen in the sun before picking - resulting in a better tasting tomato.

• GM tomatoes can tolerate a lengthier transport time. • The producers also have the advantage that all the tomatoes can

be harvested simultaneously.

GM foods were first put on the market in the early 1990s.

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INSECT RESISTANCEINSECT RESISTANCEInsect resistance is achieved by incorporating into the food plant the gene for toxin production from bacterial strains such as bacterium Bacillus thuringiensis (BT).

This toxin is currently used as a conventional insecticide in agriculture and is safe for human consumption.

GM crops that permanently produce this toxin have been shown to require lower quantities of insecticides in specific situations, e.g. where pest pressure is high.

Bt crops, such as Bt corn and Bt cotton have an inserted gene from the Bt bacteria which enables them to produce a poisonwhich shall kill the dominant pests like-Corn borer, Cotton boll worm.

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•Bt brinjal is a GM brinjal, carrying an additional gene that provides an in-built insect protection against fruit and shoot borer (FSB).

Bt Brinjal

•The development of Bt brinjal involves the introduction of the so-called cry1Ac gene from a ubiquitous soil bacterium called Bacillus thuringiensis (Bt), expressing insecticidal protein to confer resistance against FSB.

•The cry1Ac gene along with two other supporting genes namely nptII and aad genes are put together in such a way that they work in tandem to produce insecticidal protein that is toxic to the targeted insect.

Scientists have created these plants by adding an antifreeze Gene from a coldwater fish to it. • The antifreeze gene comes from the coldwater flounder, a fish that can survive in very cold conditions. This is how it was done.1. The flounder has a gene to make an antifreeze chemical. This is removed

from the chromosomes within a flounder cell

Frost resistant tomato:

from the chromosomes within a flounder cell.2.The antifreeze DNA is joined onto a piece of DNA called a plasmid. 3.This hybrid DNA, which is a combination of DNA from 2 different sources, is known as recombinant DNA.4.The recombinant DNA, including the antifreeze gene, is placed in a bacterium.•The bacterium is allowed to reproduce many times producing lots of copies

f th bi t DNAof the recombinant DNA.5.Tomato plant cells are infected with the bacteria. As a result, the antifreeze gene in the plasmid, in the bacteria becomes integrated into the tomato plant cell DNA.6.Tomato cells are placed in a growth medium that encourages the cells to grow into plants.7.Tomato plant seedling is planted.

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Golden rice is GM rice that now contains a large amount of vitamins-A, more precisely this GM rice contains the element beta-carotene which converts into Vitamin-A inside the body.Beta-carotene gives carrots their orange colour and is the reason why

Golden rice:

Beta carotene gives carrots their orange colour and is the reason whygenetically modified rice is golden.For the golden rice to make beta-carotene three new genes areimplanted: two from daffodils and the third from a bacterium.

Importance of Golden rice:• People in various countries (mostly Asians) eat only an extremelyp ( y ) y y

limited diet lacking in the essential bodily vitamins causing deathor blindness.

• The GM rice (Golden Rice) can be considered a particularadvantage to poor people in underdeveloped countries.

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Disease resistance :-There are many viruses, fungi and bacteria that cause plant diseases. Plant biologists are working to create plants with genetically-engineered resistance to these diseases.

C ld t lCold tolerance:-Unexpected frost can destroy sensitive seedlings. An antifreeze gene from cold water fish has been introduced into plants such as tobacco and potato. With this antifreeze gene, these plants are able to tolerate cold temperatures that normally would kill unmodified seedlings.

Drought tolerance/salinity toleranceDrought tolerance/salinity tolerance Creating plants that can withstand long periods of drought or high

salt content in soil and groundwater will help people to grow crops in formerly inhospitable places.

Pharmaceuticals:Medicines and vaccines often are costly to produce andsometimes require special storage conditions not readilyavailable in third world countries. Researchers are working todevelop edible vaccines in tomatoes and potatoes.develop edible vaccines in tomatoes and potatoesThese vaccines will be much easier to ship, store andadminister than traditional inject able vaccines

Phytoremediation:Not all GM plants are grown as crops. Soil and groundwater

ll ti ti t b bl i ll t f th ldpollution continues to be a problem in all parts of the world.Plants such as poplar trees have been genetically engineeredto clean up heavy metal pollution from contaminated soil.

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Future Prospects of GM cropsFuture Prospects of GM cropsThere will be a wide range of crops resistant topests, diseases & herbicides.

Food materials with improved keeping &processing qualities such as fruit much lesssusceptible to mould spoilage & reduced oreliminated natural toxicants (such asglycoalkaloids in potatoes ) or allergens ( such asallergenic proteins in nuts ).g p )

Better understanding of responses of crops toenvironmental stress & development of varietiesthat can grow in areas currently too inhospitable.

Production of high value drugs such as vaccines inhigh volume agricultural crops such as oilseed rape orlivestock such as in milk of dairy cattle.

Development of renewable & sustainable sources ofDevelopment of renewable & sustainable sources offew materials (such as plastics based on starch orvegetable oil) in designer agricultural crops such asoilseed rape, potato & maize.

Despite the technical difficulty, substantial progress isp y, p gnow being made with genetically modifying thecompositional & processing characteristics. of foodcrops

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Criticism towards GMO foodCriticism towards GMO foodMost concerns about GM foods are as follows:

Environmental hazards, Human health risks, Economic concerns,Legal concerns.

1. Environmental Hazards.(a) Unintended harm to other organisms:

•A study showed that pollen from B.t. corn caused high mortality rates in monarch butterfly caterpillars.y y p

• Monarch caterpillars consume milkweed plants, not corn, but the fear is that if pollen from B.t. corn is blown by the wind onto milkweed plants in neighboring fields, the caterpillars could eat the pollen and perish.

(b) Reduced effectiveness of pesticides:Just as some populations of mosquitoes developedresistance to the now-banned pesticide DDT, it is aconcerned that insects will become resistant to GMcrops to produce their own pesticides.

(c) Gene transfer to non-target species:Another concern is that crop plants engineered forherbicide tolerance and weeds will cross-breed,resulting in the transfer of the herbicide resistance genesresulting in the transfer of the herbicide resistance genesfrom the crops into the weeds. These "superweeds"would then be herbicide tolerant as well.

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2. Human Health Risks

Allergenicity:Many children in the US and Europe have

developed life-threatening allergies to peanutsand other foods.

There is a possibility that introducing a geneinto a plant may create a new allergen or causean allergic reaction in susceptible individualsan allergic reaction in susceptible individuals.

Extensive testing of GM foods may berequired to avoid the possibility of harm toconsumers with food allergies.

3. Economic concerns

Bringing a GM food to market is a lengthy and costlyprocess, and of course agri-biotech companies wish toensure a profitable return on their investment.

Many new plant genetic engineering technologies andGM plants have been patented, and patent infringement isa big concern of agribusiness.

Yet consumer advocates are worried that patenting thesenew plant varieties will raise the price of seeds so highthat small farmers and third world countries will not beable to afford seeds for GM crops.

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4. Legal Concerns

GM foods do not contain substantially increasedlevels of previously known toxic substances, newhazardous substances or different levels ofhazardous substances, or different levels ofnutrients than traditional counterparts.

It is crucial to address whether known orpotentially new allergens have been transferred tothe modified product.

If so, then the product must be labeled as such.This labeling policy applies to all foods to avoid thepossibility that they may unexpectedly containallergenic potential.

GENETICALLY MODIFIED ANIMALS

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Transgenic organisms , a subset of GMOs, are organisms which have inserted DNA that originated in a different

species.Some Genetically modified Organisms:

Transgenic microbes:Transgenic microbes:

Bacteria were the first organisms to be modified in the laboratory, dueto their simple genetics.

GM bacteria are used to produce the protein insulin to treat diabetes.

Similar bacteria have been used to produce clotting factors totreat haemophilia.

GM bacteria also produce human growth hormone to treat variousforms of dwarfism

Transgenic animals:• Genetically Modified (Genetically Engineered) animals are becoming

more vital to the discovery and development of cures and treatments formany serious diseases.

• By altering the DNA or transferring DNA to an animal, we can developcertain proteins that may be used in medical treatment.

• Stable expressions of human proteins have been developed in manyanimals, including sheep, pigs, and rats.

• Some chimeras, like the blotched mouse, are created through geneticmodification techniques like gene targeting.

• Transgenic animals are used as experimental models toperform phenotyping and for testing in biomedical research.

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Glofish:The GloFish is a patented brand of GM fluorescent zebra fish with

bright red, green and orange fluorescent color.A gene called green fluorescent protein (GFP), originally extracted from a

jellyfish, that naturally produced bright green bioluminescence,inserted into a zebra fish embryo, allowing it to integrate into the zebrafish’s genome which caused the fish to be brightly fluorescent underfish s genome, which caused the fish to be brightly fluorescent underboth natural white light and UV light.

Vacanti mouseThe Vacanti mouse was a laboratory mouse that looked like a human eargrown on its back. The “ear” was actually an ear-shaped cartilagestructure grown by seeding cow cartilage cells into a biodegradable ear-shaped mold.

Glofish Vacanti mouse

Sudden-Death MosquitoOxitec which is a British bio-tech company, has created GM mosquitoes,

which are programmed for sudden, early death.It involves irradiating male insects, causing mutations that make

them sterile. When released into the wild, they mate with femalespassing on lethal genes which either kills the female or at least kills theyoungs in her so then she fails to reproduce.

See through frogSee-through frog does not require dissection to see its organs, blood vessels,and eggs.Enviro pig (phytase transgenic pig)A genetically engineered pig approved for limited production whichproduces 65 percent less phosphorous in animal waste thus veryp p p p yenvironmental friendly.

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Fruit flies:In biological research, transgenic fruit flies (Drosophilamelanogaster) are model organisms used to study the effects ofgenetic changes on development (Developmental research)

i fli f f d h i l d h i hFruit flies are often preferred over other animals due to their shortlife cycle, low maintenance requirements, and relatively simplegenome compared to many vertebrates.

Cnidarians:Cnidarians have become attractive model organisms to study th l ti f i it d t i d l t lthe evolution of immunity and certain developmental processes.

FutureFuture Prospective of GM animalsProspective of GM animals

Blood replacement- Functional human haemoglobin production is inprocess in transgenic swine.

Farm animals, such as pigs, sheep or even cattle may be appropriatemodels for potential therapies for human diseases which require longobservation periods such as atherosclerosis, non-insulin dependantdiabetes, cystic fibrosis, cancer and neuro-degenerative disorders.

The pig could be a useful model for studying defects of growthhormone releasing hormone (GHRH),which are implicated in varietyof conditions such as Turner syndrome & renal insufficiency.

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ConclusionConclusionGM foods have the potential to solve many of the world's hunger

and malnutrition problems.

GM foods may help to protect and preserve the environment byGM foods may help to protect and preserve the environment byincreasing yield and reducing reliance upon chemical pesticides andherbicides.

Yet there are many challenges ahead for governments, especially inthe areas of safety testing, regulation, international policy and foodlabelling.

Thus we cannot afford to ignore a technology that has suchenormous potential benefits. However, we must proceed with cautionto avoid causing unintended harm to human health and theenvironment as a result of our enthusiasm for this powerfultechnology.