Sunday, July 28, 2013

Are Genetically-Modified Foods Bad ?

(The cartoon image above is by Peter Schrank, and appeared in The Economist on 2/25/2010.)

I'm probably going to make some of my liberal friends mad with this post. But my purpose in writing this blog is not to placate anyone, but to tell the truth as I see it.

There is a debate raging in this country (and the world) right now over genetically-modified foods (commonly called GMO's). Corporate entities like Monsanto say the GMO's are safe and want to rush them to the market, while many on the left say they are inherently unsafe and should be banned. I have always suspected that the truth probably lies somewhere in the middle.

Humans have been genetically-modifying foods since the invention of farming many centuries ago. Almost all of the foods we eat today have been modified. For instance, the original wheat plant had a very tiny head of grain and the original tomato was about the size of a thumbnail. Both were modified through genetic cross-breeding of the plants to produce the vegetables we enjoy today.

The difference is that in the past this genetic-modification took a long time through the process of cross-breeding to achieve the desirable result, while today it is done much faster through gene-splicing in a laboratory. Does that mean the new way is unsafe? Not necessarily.

One of the best things I have read on this issue comes from the writer of a blog called Saul of Hearts. The writer identifies himself this way:

I'm a crazy hippie.  I go to Burning Man every year.  I teach yoga.  I live in a co-op.  For the past two years I've been delivering organic vegetables for a local delivery service.  I've been eating vegetarian for years, and vegan for the past four months.

I'm also fascinated by genetics.  I read every book that comes my way on evolutionary theory, population genetics, and mapping the genome.  I took several classes on the subject at the University of Pennsylvania.  All told, I have a pretty solid understanding of how genes work.
The writer has written an excellent post on this subject, and I urge you to go over and read the entire post. I am reprinting here only a part of that post that I consider especially important -- a discussion of 3 common myths being circulated about GMO's. Here is what was written about these myths:
1. GMOs create more "unnatural" mutations than traditional breeding methods.
    Genetic manipulation is nothing new.  Humans have been breeding plants and animals for thousands of years.  Many of our staple crops (wheat, corn, soy), would not exist without human intervention.  The same goes for domesticated farm species.
    Whether we're using genetic modification or selective breeding, we're playing God either way.  But some people seem to think that selective breeding is "safer" -- that it allows less opportunity for damaging mutations than genetic engineering does.  This couldn't be more wrong.
    The entire process of evolution is dependent upon mutation.  UV radiation changes the structure of the DNA code in each individual organism.  Most of these mutations aren't beneficial.  Some leave out necessary proteins.  Others add useless information.  And yet, a percentage of these "errors" are helpful enough that they're passed along to future generations and become the new normal.
    If there's any danger with genetic engineering, it's that we can be too precise in our manipulation.  We can ensure that each new generation of seeds contains the exact same DNA sequence, double-checked for errors and mutations eliminated.  The "unnatural" process actually produces less mutations, not more.
2. GMOs contain animal DNA that has been "spliced" into plants.
    One of the most enduring myths about genetic engineering concerns a GM tomato which, as legend would have it, contained flounder genes spliced into tomato DNA.  While it's true that Calgene experimented with a freeze-resistant tomato, they used a "synthesized ... antifreeze gene based on the winter flounder gene" -- not a cut-and-pasted copy of the gene itself.
    Those freeze-resistant tomatoes never made it to market, but a different version called the Flavr Savr did.  Tomatoes contain a protein called polygalacturonase (PG), which breaks down the pectin in the cell walls, causing the tomato to soften as it ripens.  To create a tomato that would ripen more slowly, Calgene took the gene that encodes for the PG protein and reversed it.  This backwards strand of DNA, known as an "antisense" gene, binds to the forward-running strand and cancels it out.  Without PG, the pectin (and therefore the tomato) breaks down more slowly.  The simplicity of the process is remarkable.  No toxic chemicals, no mysterious bits of DNA.  Just a simple tweak of the tomato's own genetic code.
    But hold on a minute.  What if they had used a gene from a fish in creating this tomato?  Would the tomato taste fishy?  Would you have to watch out for fish bones in your pasta sauce?  Not unless you've added anchovies.
    Genes are basically bits of computer code that are interchangeable from species to species.  When you isolate a tiny bit of gene, it doesn't retain the essence of whichever species it came from.  You might have a bit of DNA that says simply, "Grow appendage X on the abdomen," but doesn't specify what kind of appendage.  If you put that code into a fly, it activates the part of DNA that grows a wing.  Put that same code into a mouse and it grows a foreleg.  It doesn't make the mouse any more like a fly.
3. GMO's are radioactive, cause cancer, and are bad for the environment.
    This is a trickier question to answer, and I'll be the first to admit that we need more research into the health effects of GM products.  But I'm going to bet that the answer turns out to be something like this: some GMOs are safe, and others are not.  Lumping all GMOs into the same category is like lumping all fertilizers or all pesticides into the same category.  Genetic changes are only as dangerous as the proteins they encode for -- just as in any plant.  Consider how many "natural" plants have genes that produce poisons and toxins. 
    In the case of the Flavr Savr tomato, I wouldn't be too worried.  It simply blocks a protein that the tomato itself produces.  In the case of herbicide-resistant soybeans, I'd want to know more.  What kind of herbicide is being sprayed on the plants?  Are traces of the herbicide still found in the food when it reaches our plate?
    While I voted for the labeling act that was on the California ballot last year, a simple "contains GMOs" label would be of little use to me.  I want to know what specifically about the organism was modified so I can reach my own conclusions.
I agree with the author of this post. GMO's are not inherently bad -- especially in a world where the population is growing fast. Modifications that make foods more nutritious and more productive are needed. My only concern is that some of these foods may be rushed to the market too fast -- before they have been proven to be safe. We need to find some middle ground -- that will allow modifications that increase yield and nutrition, while insuring safety. 
The government should take a leading role in this effort, but this cannot be done until we get control of the government back. Corporations currently have too much control over our government, and because of that they will automatically come down on the side of corporations. This is just one more area where corporate control of government is not in the best interest of the citizens. The issue of GMO's is not unsolvable, but it cannot be solved until we wrest back control of our government from the corporations.

2 comments:

  1. I agree that GMOs need to be thoroughly tested before being put into our food chain. It still comes down to being able to grow more food faster and without worrying about bugs or some other impediment, or taking care of starving people and all the fallout from that (brain damage, long term care, lost generations, etc). Someone who doesn't have enough food isn't too concerned whether GMOs were in their daily portion of rice or whether antibiotics were added to the feed of the chicken that could keep their children alive.

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  2. I also don't think GMO foods are inherently evil...

    The concern for me is when big corporations such as Monsanto have the entire world food supply copyrighted....and you can't even grow your own backyard veggie garden without committing a crime.

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