Transcript Genetically Modified Foods: Miracles or Monsters?

Part II: Are GM foods safe to eat
 Is DNA safe to eat?
 Could antibiotic resistance genes transfer?
 Could GM foods contain new toxins?
 Could GM foods cause allergies?
Part II: Are GM crops safe to grow?
 Could genes escape from crops to cause problems?
 What kinds of problems does gene flow cause?
 Will GM crops reduce crop diversity?
 Will GM crops reduce biodiversity?
Are GM foods safe to eat?
 Is DNA safe to eat?
All foods contains DNA -- about a teaspoon of DNA in a pound of food
Adding one gene adds roughly 1 part in a million or ~0.0001%
DNA is digested starting in your mouth
Tiny fragments gets through the digestive process
This is always happening when we eat food
It doesn’t change our genes
Are GM foods safe to eat?
 Could antibiotic resistance genes get into people?
No, DNA is broken down into tiny pieces in our digestive tracts
 Could they get into other bacteria in the gut?
Bacteria take up DNA very rarely
Transfers to gut bacteria have been looked for, but not found
Are GM foods safe to eat?
 Could GM foods contain new toxins?
Plants contain chemicals that are toxic -- in large amounts
The FDA requires chemical analyses and toxicity studies
GM foods are better analyzed than any in human history
Are GM foods safe to eat?
 Could GM foods cause allergies?
 Allergy facts
Most food allergies are caused by about half a dozen proteins
Foods contain more than 100,000 different proteins
The FDA requires developers to identify allergenicity potential
Are GM crops safe to grow?
 Could genes escape from crops to cause problems?
Gene transfer from crops to other plants is now called “gene flow”
Gene flow occurs between members of the same species
Gene flow is not a new problem in agriculture
 What kinds of problems does gene flow cause?
It depends on the crop
Are GM crops safe to grow?
 Will GM crops reduce crop diversity?
The monarch butterfly incident
Bt genes in Mexican land races
http://www.scu.edu/cas/research/images/smecology.jpg
http://www.newsroom.ucr.edu/images/releases/997_0.jpg
http://www.botany.org/plantsciencebulletin/images/54-2_raven.jpg
 Will GM crops reduce biodiversity?
“Nothing has driven more species to extinction or caused more
instability in the world’s ecological systems than the development
of an agriculture sufficient to feed 6.3 billion people.”
“To assert that GM techniques are a threat to biodiversity
is to state the exact opposite of the truth.”
“The less focused and productive this agriculture
is, the more destructive its effects will be.”
Peter Raven
Director of the Missouri Botanical Garden
Rapid acceptance of GM crops
Fusarium ear rot
(fumonisins)
Kernel rot (aflatoxin)
http://www.isaaa.org/default.asp
http://www.isaaa.org/default.asp
GM crop statistics 2008
 GM crops were grown on 125 million hectares in 25 countries in 2008
Biological pest control is better than using chemical pesticides
http://evolution.berkeley.edu/evosite/relevance/images/pestspray.jpg
 Pesticides kill both beneficial and harmful insects
http://www.communityipm.org/toxictrail/issue2-Poisoning.htm
 There are 25 million cases of pesticide poisoning/year
Resistance to molecular crop enhancement
cujtokyo.files.wordpress.com/2007/10/gmo-prot...
www.greenpeace.org/raw/image_full/france/
http://www.bayweekly.com/year01/issue9_38/images9_38/lead04protestors.jpg
https://www.penelopebokhandel.no/bookcovers/978/0/6/7/4/0/2/9780674029736.jpg
Indirect effects of anti-biotech attitudes
Rob Paarlberg
http://news.bbc.co.uk/media/images/38232000/jpg/_38232577_levy150.jpg
Resistance to molecular crop enhancement
news.bbc.co.uk/media/images/38455000/gif/_384..
Zambia’s President
Levy Mwanawasa
Famine areas highlighted in yellow
gbgm-umc.org/.../lisutuagdeadfarmfield.jpg
Molecular methods of crop improvement:
why the resistance?
www.nlm.nih.gov/.../smallpox/sp_vaccination.html
A cartoon about smallpox vaccination from 1802 by British satirist James Gillray
Are GM foods safe to eat?
What’s the bottom line?
A GM food is no more likely to cause a
problem than the same non-GM food
Are GM foods safe to grow?
What’s the bottom line?
A GM crop is no more likely to cause a
problem than the same kind of non-GM crop