Generic modified food

1. Genetically Modified Foods
By:-
kishan koyani
RDMSFT181901
3

2. Introduction
 Role of biotechnology.
 scientists can transfer genes from one organism to another unrelated organism, producing
what is now known as “genetically modified organism” or “transgenic animal/ plant”.
 Any food produced this way is called Genetically modified food i.e. foods obtained by
added or deleted gene sequence.
 More technically, genetically engineered (GE) food are defined as foods produced from
plants, animals and microbes that have had their genetic code modified by the selective
introduction of specific DNA segments.

3. Why Produce GM Food?
 From economical and agricultural standpoints, it is advantageous to grow crops that have
higher yield or improved quality, pest or disease resistance, or tolerance to heat, cold and
drought.
 Desirable genes may provide means for plants to combat these conditions.
 The development of transgenic technology allows useful genes from various living
sources to be brought together in a relatively simple manner.

4. History of GM foods
 In the 1960s, a lot of breakthroughs were recorded in the field of genetics. It was proven
that this new knowledge had the potential to revolutionize food production, thus creating
huge benefits for the world (Hammer, 2003).
 By 1972, another scientific breakthrough was recorded by Paul Berg, who joined together
DNA from two different organisms, to create the first recombinant DNA molecule
(Griffiths, 2006).
 This breakthrough was followed by a pioneer study in which Stanley Cohen and Robert
Boyer inserted DNA from an African clawed toad into the Escherichia coli bacterium.

5. Cont.
 1960-1970 : Isolation of restriction enzymes and their use to analyse DNA structure.
 1981-1982 : First transgenic animals (mice) produced.
 1983-1985 : First transgenic plants produced.
 1990-1992 : First transgenic cereal plants (maize and wheat)
 1992-1993 : Regulations for deliberate release of genetically engineered organisms.
 1994 : Genetically engineered tomato marketed in USA.

6. Types of GM Foods
1. First-generation crops:-
Examples of such crops are herbicide resistant soybean, insect resistant, maize, and
herbicide and insect-resistant potato.
2. Second-generation crops:-
Examples of such crops include rice with a higher level of betacarotene, tomatoes with
higher levels of carotenoids, maize with increased vitamin C, soybean with improved amino
acid composition, and potatoes with higher calcium content.
3. Third Generation:-
may provide health benefits. Yet, another objective may be to create “pharmaplants” to help
produce active pharmaceutical products.

7. Current Status of GM Food in India
 India is a signatory to the Cartagena Protocol on Biosafety (CPB) since 2003.
 India's apex biotech regulatory committee, the Genetic Engineering Approval Committee
(GEAC) that functions as a statutory body under the Environment Protection Act 1986 of
the Ministry of Environment & Forests (MoEF), has been changed to Genetic
Engineering Appraisal Committee in July 22, 2010.
 Biotechnology Regulatory Authority of India (BRAI) Bill.

8. Advantage of genetically modified foods
 Improved yield
 More resistant to disease
 Less likely to be damaged by insect
 Tolerance to herbicides
 Better nutritional value
 Increased shelf life
 Improvement in health and environment

9. Cont.
 Better climatic survival by increasing tolerance to draught, flood or frosty conditions to
allow the use of previously inhospitable land.
 Higher crop yields
 Reduced farm costs
 Increased farm profit

10. Herbicide-Resistant GM Crop
 Weed infestations destroy about 10 percent of crops worldwide.
 Herbicide-tolerant varieties are the most widely planted of GM crops, making up
approximately 70 percent of all GM crops.
 Glyphosate
examples:- Corn, soy, cotton, canola, rice, alfalfa, beet, flax

11. Insect-Resistant GM Crops
 Insect damage is one of the most serious threats to worldwide food production.
 The most widely use GM insect-resistant crops are the Bt crops(Bacillus thuringiensis).
 Each insect species has specific types of gut receptors that will match only a few types of
Bt Cry toxins. As there are more than 200 different Cry proteins.
Examples:- Corn, cotton, potato, tomato

12.  Frost resistance crop
 Drought and Salinity resistance crop

14. Cont.
1.Indirect method-
 Agrobacterium mediated gene transfer.
2.Direct methods-
 Particle bombardment (biolistics).
 Micro projectile gun method.
 Electroporation.
 Silicon carbide fibres.
 Polyethylene glycol (PEG)/protoplast fusion.
 Liposome mediated gene transfer.

15. Agrobacterium mediated gene transfer:-
 Agrobacterium:-
1. Soil borne, gram negative, rod shaped, motile found inrhizosphere.
2. Causative agents of “Crown gall” disease of dicoltyledones.
3. Have ability transfer bacterial genes to plant genome.
4. Attracted to wound site via chemotaxis in response to chemicals(sugar and Phenolic
molecules: acetosyringone) released fromdamaged plant cells.
5. Contains Ti plasmid which can transfer its T-DNA region intogenome of host plants.

16. Ti plasmid

17. Process of T-DNA transfer
 1. Identify a suitable explants.
 2. Co-cultivate with the Agrobacterium.
 3. Kill the Agrobacterium with a suitable antibiotic.
 4. Select for transformed plant cells.
 5. Regeneration of whole plant.

18. Cont.

19. Advantage and Disadvantage
1. Advantages
 Agrobacterium mediated gene transfer is a natural means of transfer and therefore
perceived as more acceptable technique.
 Agrobacterium capable of infecting intact plants cells, tissue and organs, tissue culture
limitations are very less.
 Transformed plants can be regenerated more rapidly.
 Stability of gene transferred is excellent.
2. Disadvantages
 It has limitation of host range.
 Some of the important food crops can not be infected by this.
 Sometimes, the cells in a tissue that are able to regenarate are difficult to transform.

20. Electroporation technique
 Is the process where by electrical impulses of highfield strength are used to reversibly
permeabalize cellmembrane to facilitates uptake of large molecules,including DNA.
 It has been used for long time for transient andintegrative transformation of protoplasts
 1 to 1.5 k V. so uses low capacitance hence shortdecay time .
 It can be used to deliver DNA into plant cells and protoplasts.
 Plant materials is incubated in a buffer solution containingDNA and subjected to high-
voltage electric pulse.

22. Advantages and disadvantages
 Both intact cells and tissue can be transformed.
 The efficiency of transformation depends upon the plantmaterials, electroporation and
tissue treatment conditions usedfor transformation.
 ~40 to 50% incubated cells receive DNA.
 ~50% of the transformed cells can survive.

23. Biolistic/Particle bombardment
 Is the most powerful method for introducing nucleic acids into plants, because the
helium pressure can drive micro carriers through cell walls.
 Is much easier and less time consuming than micro injecting nucleic acids into plant
cells or embryos.
 Allows transformation of animal cells that have unique growth requirements and that are
not amenable to gene transfer using any other method.
 Requires less DNA and fewer cells than other methods, and can be used for either
transient or stable transformation.

24. Principle
 The gold or tungsten particles are coated with
the DNA thatis used to be transform the plant
tissue.
 The particles are propelled at high speed into
the targetplant material where the DNA is
released within then celland can integrate into
the genome.

25. Advantages
 Method is easy to use, rapid and versatile.
 Transient or stable expression is possible.
 Small amounts of nucleic acids and few cells are required for efficient transformation.
 Potentially toxic treatments such as using viruses or chemical are avoided.