Transcript IntroToGMOs
From Cows to Canola
An Introduction to
Genetically Modified Organisms (GMOs)
Traditional Breeding
Traditionally, plants and animals with favorable traits
have been bred to perpetuate these traits in offspring.
+
=
The pug and beagle have been bred to produce the ‘puggle’,
a mixed breed with both pug and beagle traits.
Traditional Breeding
This has been
particularly important
in agriculture, where
crops and animals
are prized for having
certain traits.
Advances in Breeding Methods
Over time, more
sophisticated breeding
practices emerged, such
as mutation breeding.
This is a process in
which organisms are
exposed to chemicals
or radiation.
This changes their
DNA in an effort to
produce new desired
genetic traits.
Mutation breeding (gamma radiation) was used
to develop these drought-resistant soybeans.
Mutation Breeding
MB has been applied for decades
to yield products such as:
Rio Red grapefruit
Golden Promise Barley
(used in fine beers)
Nearly 200 types of
bread wheat
Beans, lettuce, rice, oats
How is Genetic Engineering Different?
Genetic engineering is a
laboratory technique
that allows for greater
precision and a wider
array of possibilities.
For example, genes
from one species
can now be inserted
into another.
Example 1: A Golden Opportunity
Daffodil and soil
bacterium genes were
introduced into
white rice to produce
Golden Rice.
White Rice vs. Golden Rice
A Golden Opportunity
The golden color results
from elevated levels of betacarotene, which boost the
nutritional value of the rice.
Golden Rice will be
grown in places that
lack adequate sources
of beta-carotene.
Example 2: Antioxidants, Anyone?
Genes from the
snapdragon flower were
incorporated into
tomatoes to create this
antioxidant-rich fruit.
Meaningful Silence
Transferring genes
isn’t the only way
genetic engineering can
be applied. It has
other uses, too!
For example, genetic
engineering allows us
to “shut off” genes
within an organism so
that the products they
normally express are
not produced.
Gene silencing techniques have been used
to lower the allergenicity of peanuts.
Genetic Engineering: Other Advantages
Plants
• Increased crop yields
• Pest resistance
• Environmental tolerance
(to drought, extreme
temperatures, etc).
• Virus resistance
Other organisms
(animals, fish, etc.):
• Faster growth rates
• Ability to produce valuable
proteins in animal milk
• Ability to overcome limited
availability of certain
resources (eg, rChymosin)
Example 1: SunUp Papaya
The papaya ringspot
virus was on course
to wipe out the Hawaiian
papaya industry.
This prompted the
development of the
SunUp papaya,
which is genetically
modified to be resistant
to this virus.
The SunUp papaya is believed to have
rescued Hawaii’s ravaged papaya industry.
Example 2: Got Fibrinogen?
Fibrinogen is a
protein that helps
blood to clot.
GM cows that secrete
fibrinogen in their
milk can make this
protein widely
available to patients
who need it.
Example 3: GM foods have been
a regular part of our diets for years.
An estimated ~75% of
processed foods in the United
States contain genetically
modified ingredients.
Examples include canola oil
and rChymosin, an ingredient
found in many commercially
available cheeses.
Concerns about GMOs
‘Superweeds’
Ecosystem disruption
Unknown long-term
health effects
Inadequate regulation
Allergens transferred
to new foods
?
?
?
?
?
Moral concerns
(‘playing God’?)
?
?
Cross-pollination
?
?
?
?
?
?
?
Example: 2S Albumin
Pioneer Hi-Bred
wanted to boost the
nutritional value of its
soy-based animal feed.
It developed GM
soybeans containing
2S albumin, a protein
from Brazil nuts.
2S albumin is a human
allergen, and the
allergen was transferred
into the beans.
Although they were intended solely
for animal consumption, Pioneer’s
soybeans were not released for use.
The Future
Genetic engineering has
opened the door to
countless possibilities in
food, health, and beyond.
However, each new
genetically modified
organism brings certain
unknowns.
Careful monitoring and
testing, regulations, and
other factors will all play a
role as genetic engineering
plays a growing part in
our daily lives.
Review
Genetic engineering enables us
to do something that isn’t done
via traditional breeding or
mutation breeding. What is it?
Answer: Transfer a Gene from
One Species to Another
This GM lettuce carries
the insulin gene. It
relieves diabetes in
mice and holds promise
for future applications
for humans.
Review
Describe two ways in which
the genetic makeup of an
organism can be changed
via genetic engineering.
Review
1. A foreign gene can be added to an
organism to create a new trait in that
organism.
2. An existing gene within the organism
can be “shut off” so that the product it
normally expresses is not produced.
Review
What kinds of
advantages can genetic
engineering impart?
Review
Increased crop yields
Virus resistance
Pest resistance
Faster growth rates
The ability to produce
important proteins in
animal milk
Environmental tolerance
(to drought, extreme
temperatures, etc).
Enhanced nutritional
value
Ability to overcome limited availability
of certain resources (eg, rChymosin)
Review
What are some of the
concerns people have about
genetic engineering?
Review
Development of
‘superweeds’
Unknown long-term
health effects
Allergens transferred
to new foods
Cross-pollination
Ecosystem disruption
Inadequate regulation
Moral concerns
(‘playing God’)
Discussion
1.
What do you think about genetic engineering?
2.
Do you view it as more helpful or harmful? Why?
3.
Would you eat foods that you knew were
genetically modified? Why or why not?
4.
How do you think GM foods should be regulated?
Image Citations
(by slide number)
1. http://www.cartoonbank.com/2000/We-would-like-to-be-genetically-modiied-to-taste-like-Brusselssprouts/invt/119426
2. http://panzercow.files.wordpress.com/2010/02/pug.jpg, http://www.krittercards.com/images/beagle1.jpg,
http://petsworldri.com/yahoo_site_admin/
3. http://media-cdn.tripadvisor.com/media/photo-s/01/4f/cb/a6/colorful-vegetables-at.jpg,
http://news-libraries.mit.edu/blog/date/2009/01/page/2/
4. http://www.pnri.dost.gov.ph/pnri.php?pnri=nrd
5. http://www.texascitrusexchange.com/rio_red_facts.htm,
http://www2.science.unsw.edu.au/news/newsArchive.html
6. http://en.wikipedia.org/wiki/File:Genetic-engineering-wheat.jpg
7. http://www.jamesandthegiantcorn.com/2009/11/14/genetically-engineered-crops-rice/
8. http://www.learner.org/courses/envsci/unit/text.php?unit=7&secNum=7, http://www.goldenrice.org/Content3Why/why1_vad.html
9. http://webecoist.com/2009/09/01/10-more-intriguing-genetically-modified-fruits-veggies/
10. http://runforlife3.wordpress.com/2009/04/15/peanut-peanut-butter-and-jelly/
11. http://homegardeningzone.com
12. http://www.ctahr.hawaii.edu/seed/seeds.asp
13. http://news-libraries.mit.edu/blog/date/2009/01/page/2/
14. http://images.businessweek.com/ss/07/12/1206_biotech_brunch/source/5.htm,
http://www.seriouseats.com/2007/04/stinky-wine-shops-now-serving.html
16. http://www.ctahr.hawaii.edu/biotech/safety.html
19. http://floridatrend.com/article.asp?aID=89695759.8573667.651898.21069602.9810479.224&aID2=50137