Transcript Genetically Modified Plants - Georgia Public Broadcasting

Genetically
Modified
Plants
Stacy Byrd
Fernbank Science Center
November 3, 2007
The end of the hunter-gatherer:
AGRICULTURE
Mural from Catalhoyuk excavation,
Turkey 8,000 – 10,000 years ago
Traditional
breeding
methods

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Artificial selection for
traits to create new
hybrids
Slow, requiring many
generations
Limited to traits within
species that will
interbreed
Engineered
Plants



Photo: Univ. of Minn.
Desired trait is linked to a
specific gene.
Gene can be isolated and
inserted into the target
plant’s genome regardless
of the relatedness of
donor to recipient.
New plant variety can be
produced relatively
quickly.
Famous Modified Plants:

Source: Santa Monica College Human Genome timeline
Flavr Savr Tomato
Developed by
Calgene in late
1980’s and approved
by the FDA in 1994.
“Antisense”
technology
Famous modified plants:
 Golden
Rice
insertion of gene
from daffodil to
produce beta
carotene
(pro Vitamin A)
Source: www.scienzz.com
Vitamin A deficiency in the world
Source: World Health Organization
The most common modified crop
plants in current production
display one or both of these traits:


Herbicide Tolerance – allows crop to be
sprayed with an herbicide: kills the
weeds but doesn’t damage the crop,
e.g. Round-up Ready
Systemic Toxicity to Insect Pests – plant
tissue produces a natural pesticide e.g.
Bt cotton
Plant Biotechnology

“Conversations about Plant Biotechnology” videos
sponsored by Monsanto Corporation .
Frankenfoods ?
RISKS
Source: www. bioteach.ubc.ca
RISKS to
non-target species?
RISKS to human health?

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Not a single verified case
of allergic reaction due to
GM foods.
If a modified plant were
to contain a protein from
one of the most common
food allergens, it would
have to be labelled for
the consumer.
Source: Univ. of Georgia CAES
Could a genetically modified
allergen-free peanut be on the horizon?
The DNA Files
Designing the Garden: Food in the Age
of Biotechnology


Some say manipulating genes in plants
and animals is the solution to world
hunger; others say genetically modified
organisms are neither safe to eat or to
grow. How do we understand what’s really
on our dinner plate?
Audio Source: www. DNAfiles.org