GENETICALLY MODIFIED FOOD PLANTS

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GENETICALLY MODIFIED FOOD - PLANTS
Cheaper more nutritious food
Frankenfood
or
Without GMOs
With GMOs
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DNA
RNA
PROTEIN
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(No Transcript)
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PLANTS ARE MODIFIED USING RECOMBINANT DNA
Recombinant DNA is a technique that allows us to
move one or more genes, the inherited
instructions for a specific desirable trait from
one organism to another. There are 30,000
genes in the genetic code (DNA) of a higher plant
or animal. When a gene has been identified that
codes for a protein that would give a plant a
desirable trait, that particular gene (a piece of
DNA)can be snipped off the DNA strand with special
enzymes and enzymatically reglued (recombined)
with DNA from another organism to form a new DNA
molecule. This DNA is then transferred into the
desired organism and the DNA becomes part of that
organisms and all its descendants genetic
material. That organism and its descendant's
will all have the desired trait.
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X
ADDING A SINGLE GENETIC TRAIT TO AN ORGANISM DOES
NOT MAKE IT INTO A NEW ORGANISM
DNA for one trait
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TRADITIONAL BREEDING CAN RADICALLY ALTER PLANT
MORPHOLOGY (From Teosinte to Maize)
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BIOTECHNOLOGY ALLOWS US TO BREED PLANTS WITH
DESIREABLE TRAITS FASTER
Think of the genetic information of an organism
as a book. If each unit of information in an
organisms genetic code is represented as a
letter, it would take 1,700,000 pages, or 1,700
books of 1000 pages each, to contain all the
information in a wheat plant.
Traditional breeding combines the instructions on
1.7 million pages from one parent with that of
1.7 million pages from the other parent. The
offspring may contain information for a desirable
trait, such as high levels of vitamin E but may
also include an undesirable trait, such as
lower yield or bad taste.
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With Biotechnology , the page that contains the
information to make large amounts of vitamin E
or other desired characteristics can be
identified, snipped out and inserted into a plant
with high yields. This plant will now have both
high yields and make high amounts of vitamin E.
Instructions for making Vitamin E


High Vitamin E
Biotechnology modified plants currently in the
marketplace have only a half a page of new
information out of the 1.7 million page genetic
code.
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Another advantage of biotechnology is that in
traditional breeding only traits from the same
species can be transferred to a different variety
of the same species. Using genetic engineering we
can transfer an advantageous trait from any
species to another. Scientists wish to improve
the nutrient content of plants, or to use plants
to grow medicines, have more healthy oil content,
etc., and not make dancing grapes.
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TRAITS THAT HAVE BEEN INTRODUCED INTO PLANTS
USING GENETIC ENGINEERING
Viral Resistant Plants
Herbicide Resistant Plants
Insect Resistant Plants
Golden Rice
Vitamin A Enhanced
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Viral Resistance

• Plants like animals can be infected by viruses.
  Plant viruses only infect plants. Individual
  viruses are plant family
• specific. In example Tobacco Mosaic Virus can
  infect the Solanacea family tobacco, tomato,
  peppers, eggplant,
• squash, etc.
• Plant viruses are made up of an outer coat of
  protein (see picture below), and an inner core of
  genetic material,
• either RNA or DNA.
• Plant viruses usually do not kill their hosts but
  usually cause slower growth, decreasing the
  agronomic value of
• the crop, from anywhere from 5 to 100.
• Crop plants infected with plant viruses are not
  destroyed, but are sold everyday in the
  supermarket. All humans
• and animals now alive, or ever alive, have eaten
  many and lots of different plant
  viruses,containing both the
• viral genetic material and the viral coat
  protein.
• Scientists found that if they inserted into a
  plant, the gene for the coat protein of a virus
  which attacked that
• plant, and the plant using this genetic
  information then made many copies of the viral
  coat protein, the plant was
• resistant to the virus.

6. Since we have all already eaten many, many
viruses in infected plants, we know that
eating plant viral coat protein is safe and
non-allergenic. 7. In the body, viral coat
proteins, whether from transgenic plants or from
virus infected plants is digested like any
other protein.
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INSECT RESISITANCE

• Bacillus theringinesis, a bacteria, makes
  proteins that are toxic to insects. These
  proteins are encoded by genes
• named cry.
• These proteins are toxic ONLY to lepidoptera -
  butterflys and moths.
• These proteins are NOT toxic even to other insect
  families and are absolutely not toxic to humans.
• For 50 years, organic farmers have sprayed their
  crops with Bacillus theringinesis. Here, when the
  insect eats
• the plant covered with the bacteria, it eats
  the toxic protein inside the bacteria and is
  killed by the cry protein.
• If you have eaten organically grown produce, you
  have eaten Bacillus theringinesis and cry
  protein.
• Scientists have isolated the genes for many cry
  proteins. One gene that codes for a particular
  cry protein
• is inserted into a plant and the plant now
  makes that protein in all its cells. The plant
  is now resistant
• to some(many) Lepidoptera species.
• Food safety is determined by the US Food and Drug
  Administration.
• Food wholesomeness by USDA.
• Enviromental issues by the EPA.
• All food into which genes are inserted must be
  approved by the FDA, USDA and EPA.
• Note If you cross two varieties of
  nonrecombinant plants, both of which are safe to
  eat, the offspring must
• still be evaluated by the USDA, EPA and
  FDA.
• Alternatives to Insect Resistant Plants
• Spraying with insecticides - Most sprayable
  insecticides work as neurotoxins. Neurotoxins
  are toxic to the

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Herbicide Resistance

• Genes have been inserted into plants which make
  the plants resistant to herbicides.
• The rationale for making herbicide resistant
  plants, is that once the crop plant is
• growing, weeds must be removed mechanically or
  by hand. Mechanical or hand
• removal of weeds takes time and energy and
  increases the cost of food. It is less
• expensive and requires less time for the farmer
  if he can spray his crop
• to remove weeds.
• Two different methods are used to provide
  herbicide resistance
• a. The insertion of a gene that encodes 5-EPSPS
  (5-Enolpyruvyl-shikimic acid
• 3-phoshoric acid synthatase), or
• b. The insertion of a gene that encodes PAT
  (phosphinothricin-N-acetyl-transferase)

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5-EPSPS
The 5-EPSPS gene encodes the information for
making the 5EPSPS enzyme. This enzyme is normally
present in plants and is necessary for plants
to synthesize the amino acids Tyrosine,
Tryptophan and Phenylalanine. Monsanto has
genetically modified plants to makein addition to
the normal 5EPSPS, a second very similiar
5EPSPS. Normal 5-EPSPS is inactivatedby
glyphosate, the active ingredient in Roundup. If
5-EPSPS is inactivated by glyphosate, the
plant cannot make Tyrosine, phenylalanine or
Tryptophan. These 3 amino acids are essential
building blocks of proteins, so without them the
plant cannot make any proteins and dies. The
gene Monsanto inserts into plants makes a
slightly modified 5-EPSPS protein which is not
inactivated by glyphosate. Thus, these plants are
resistant to Roundup. Some of these Roundup
Ready plants have an additional gene inserted
into their chrosomes. This gene codes for a
protein called glyphosate oxidase. This protein
allow the plant within its cells to degrade
glyphosate into two parts, one which is exuded
into the soil by the plant and degraded by
microorganisms for food, and the other which
the plant can convert into chemicals it can use
to survive.
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PAT
Plants that make the enzyme PAT are resistant to
glufosinate herbicides (Basta, Ignite, Liberty,
Harvest, and Finale). These herbicides inactive
a protein called glutamine synthatase. Glutamime
is another essential amino acid necessary as a
building block for making proteins. Again, if the
plant cannot make proteins, it dies. Plants that
have been genetically modified to contain the
gene for PAT and make the PAT protein are now
capable of inactivating the chemical glufosinate
and can survive spraying with these
herbicides. Glufosinate is highly biodegradable,
has no residual activity, and very low toxicity
for humans and wild fauna. This means food can
be sprayed with glufosinate and is safe to eat a
few days later.
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The Future

• Food with enhanced vitamin content.
• Food with different balance of fats to help
  prevent heart disease
• Immunization by eating a banana. (No shots!)
• Plants capable of growing in soils containing
  high amounts of salt.
• Plants capable of resisting short periods of
  freezing. (We wont lose the orange crop.)
• Plants resistant to bacterial and fungal (mold)
  infections.
• Pharmaceuticals
• Etc., etc., and my favorite, a tomato that you
  can buy in the supermarket that
• tastes like a tomato.

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More info
A couple of web sites Neutral http//ccr.ucdavi
s.edu/biot/index.html http//www.agbiosafety.unl.e
du/ Lists of Pro, Con and Neutral
Sites http//csanr.wsu.edu/InfoSources/biotechnolo
gy.htm
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How Transgenic Plants are Made
Agrobacterium is the cause of crown gall
disease. Agrobacterium genomes have 1 chromosome
and sometimes contain a extra small piece of
DNA called a Ti plasmid. To cause crown gall
disease, Agro transfers two genes into the
plant. The genes are inserted (glued)
permanently into a plant chromosome. Scientists
have been able to remove the disease causing
genes from the Ti plasmid. We can then grow up
Agrobacterium with this disarmed plasmid,
isolate the plasmid and insert any genes we
want into the plasmid, put the new plasmid back
into Agrobacteria, and have the bacteria
transfer these new genes into the plant.
Agrobacteria
A crown gall
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REGULATION OF GMOs
The US Department of Agriculture (USDA) and the
Animal and Plant Health Inspection Service
(APHIS) develop policy, regulations and review of
all environmental (field trials to commercial
plantings of genetically engineered
microorganisms, animals and plants). Permits are
issued by APHIS after scientific review of of
potential environmental impacts.
The Food and Drug Administration determines the
safety of new plant or animal products. It does
not focus on the mechanism by which they were
produced. New plants produced by Biotechnology or
by traditional breeding methods must be tested
for safety and nutrition in an alike manner.
The Environmental Protection Agency establishes
regulations and registration requirements based
upon the toxicity and environmental impact of new
pesticidal products or plants with introduced
pesticidal traits.
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Environmental Concerns

• Monarch Butterfly - Exhaustive
• scientific studies have shown no
• effect of BT toxin in corn on
• Monarchs.

• Escape of a genetic trait
• into the environment - EPA assesses
• the danger of release of a genetic
• trait into the environment.

• Patents on technology - Patents are given on
  GMOs. Third World
• Countries have been given the technology and
  genes to produce
• plant GMOs. No patent charges will be made to
  individual farmers
• who farm less than 50 acres.
• APHIS - Maintains seed stocks of all plant
  species of agronomic
• importance.

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ALLERGY PRECAUTIONS
At this time, US companies are not exploring use
of genetic material from foods commonly
associated with allergies, such as peanuts or
wheat. Molecular Biologists and Biochemists know
that most allergens have common structural
characteristics and proteins with such
characteristics are avoided. Additionally, all
plant GMOs, the purified proteins are tested on
animals first(usually two to three vertebrate
species. Most proteins that cause allergies are
digested slowly. All plant GMOs are tested to
determine how quickly they are digested.
Starlink corn was approved only for animal feed
because the transgenic protein in it was digested
slower than the approved limits. All Biotech
companies have agreed voluntarily not to ask for
licensing of GMOs unless they can be approved
for both animal and human consumption.