Since last month’s post on the role of technology in feeding the world, I’ve been thinking a lot about the fundamental issue of GMO’s.

A primary GMO-related fear is the unknown consequences of the genetic manipulation.  I won’t discount this concern, but I would like to put it into perspective.

Every bit of variation in all the food crops (plant or animal) we consume arises by genetic mutation.  As humans domesticated plants and animals, we selected mutants (sounds a lot scarier than ‘variants’, doesn’t it?) that suited our needs better.  These mutations had some visible difference (color, faster growth, better taste), but beyond what we could see, we had NO idea what other changes were caused by the mutation.

Since early in this century, plant breeders have produced new varieties of all sorts of plants by something called “mutation breeding“.  Seeds are subjected to some form of mutagenizing agent, such as a chemical, UV light or x-rays.  Thousands are planted to screen for and select desirable mutations.  This is a primary way in which disease-resistant varieties of vegetables, fruits and other crops are developed.  The FAO maintains a database with thousands of catalogued varieties.

Even heirloom varieties are mutants.  Are you familiar with those cool zebra-striped heirloom tomatoes?  Those stripes are caused by a “jumping gene” that randomly inserts itself in the genome, sometimes disrupting a color gene.

At least the GMO varieties had to go through some sort of characterization of their biochemical properties.

1. Rebecca T. of HonestMeat Says:
   January 11th, 2009 at 10:47am

   The majority of commercial GMO crops are either Roundup Ready or include the Baccilus thurgensis bacteria in them. These differ dramatically from mutation breeding that selects for different traits within a species. As a result, there has been exponential growth in the last 15 years of glyphosate-resistant weeds and now Bt is loosing its effectiveness as a pesticide (see the article below). All herbicides and pesticides have a useful life- genetically engineering them into crops (as either resistance to an herbicide or inclusion of a pesticide) will only shorten the usefulness of those chemical resources for the rest of agriculture. I think most people are not afraid of the method, they are afraid of the consequences.

   http://www.sciencedaily.com/releases/2008/02/080207140803.htm



2. Sara Says:
   January 11th, 2009 at 12:07pm

   Rebecca:

   Thanks for the link to the great article. It is nice to see some scientific data (and seemingly unbiased) on the subject. Note that there has been a previous case of Bt resistance from sprays, and this is the first case from GMO.

   You make a very valid point about effectiveness and resistance that points to a debate on widespread use of many things such as antibiotics, pesticides, etc. How much do we limit use of something that has economic benefit because of the possibility of downstream resistance?



3. Rebecca T. of HonestMeat Says:
   January 12th, 2009 at 5:46pm

   If we know that the useful life of a pesticide or antibiotic will be cut in half due to a new technology that dramatically increases overall use (for corporate profits), perhaps we should use our noggins to think of something different. For example, we know fully well at this point that sub-therapeutic dosages of antibiotics in chickens and other meat & dairy animals have made several antibiotics used in humans less effective. There are new strains of bacteria that are building resistance to antibiotics used in livestock, such as MRSA (which is transferable to humans). I would say without any doubt that reducing the effectiveness of human medicines for increased profits in the livestock industry is never worth it. The economic benefits of today should not destroy the quality of life for our children.