Friday, August 10, 2012

GM: truth or consequences?

Whenever science tries something new, and especially perhaps if it is tried by a big business, you can count on a reaction.  But when is it just reactionary?

We are skeptical and critical of many things in science, including crass or misleading commercialism, hyperbole, or waste of research resources in genomics.  But we try to keep it to the science and to be fair and balanced (not in the Fox 'News' sense!).

GM crops have created much contentious controversy.  Many have condemned the capitalist exploitation that is involved in many instances, or the push towards transgenic monocropping.  Sometimes this has been sociopolitical protest.  It's a mix of back-to-the-land nostalgia, belief in mixed, small-farm agriculture, and feeling for the exploited farmers around the world--and allegations against GM crops.  And anger at agri-business for making farmers buy new seed each year.

The scientific (non-political) complaints have been, essentially, that:  (1) the crops spread genomic uniformity in a world where evolutionary variation is required, so that pests can eventually overcome the anti-pest modifications in some GM crops; (2) the transgenes may spread to wild strains, making future diversity unavailable even if needed; (3) the transgenic crops may devastate needed insect pollinators, pest-eaters, and so on; and (4) the crops may contain items harmful to their consumers (us, or our livestock).

GM manufacturers may be greedy and crass, and worthy of scorn and deserving of regulation, but they certainly do at least test their modified crops. They aren't pulling their claim that the transgenic protein changes aren't harmful to people or cattle out of thin air.  Years of use have not revealed many, if any, serious problems of this sort.

So when a story is circulated like this one, that animals fed on GM produce lose fertility and have stunted growth, how should we react? 
Yet another study has concluded that feeding animals GMOs results in higher rates of infant mortality and causes fertility problems. Russian biologist Alexey V. Surov and other researchers fed Campbell hamsters (which have fast reproduction rates) Monsanto GM soy for two years. It should be noted that hamsters do not evolutionarily eat soy—just as cows fed Monsanto corn are actually ruminants and would not naturally eat corn.
Many animals on the GM diet even displayed rare, strange pathologies like hair growing in recessed pouches inside their mouths. “Some of these pouches contained single hairs,” said Surov in Doklady Biological Sciences, “others, thick bundles of colorless or pigmented hairs reaching as high as the chewing surface of the teeth. Sometimes, the tooth row was surrounded with a regular brush of hair bundles on both sides.  The hairs grew vertically and had sharp ends, often covered with lumps of mucous.” Surov and other authors concluded that because rates of hairy mouths occurred more frequently in third-generation GM-fed animals, the condition may have resulted of the GM feed. Surov says contaminants and herbicide residue (like Roundup) could be to blame as well.
We need to be as suspicious of underlying motives of authors of such reports, just as we are of positive claims by promoters of GM crops.  If this report truly indicts GM soy, how could such a result not have been noticed before?

First, was this study well-conducted?  Did they feed control animals non-GM soy (hard to find, granted) so they could eliminate the possibility that any experimental effect was due to the transgene rather than simply a diet of soy?  And, what about the possibility that it is contaminants and herbicide residue that could be to blame?   In either case, indicting the GM diet is premature.  And note, we aren't defending GM foods here, just good science!  Using bad science even for a good cause isn't much help to that cause.

And, second, to show harm, drug companies or regulators often hugely overload test animals with exposure to the test agent.  This could be the case here, too.  If so, one could defend the GM crops by saying that many things in massive doses cause harm, but are harmless and routine in daily life.  In that sense, this story is an exaggeration that misrepresents risk--even if there are no problems with the study.

Another point of view would be that most things in evolution are gradual, small, and slow, but accumulate over time.  It is obvious from the accumulating data about GM crops that they don't have dramatic effect or they'd' not ever be marketed, even by agribusiness.  The thing to fear and object to, if there is anything like that, would be small risks to individuals, even if substantial to large populations.

We avoid unnecessary X-rays because though the risk is small, on a population basis they may in fact cause many cases of disease.  Likewise here, if GM crops do have some risk, it is almost necessarily going to be small.  Again, if it were very large, nobody would ever market the crops.

If this is the case here--and we can't judge just from this story--then it's an instance of the politics of population risk vs corporate gain, or gain in efficiency, pest-control, or whatever.  The political issues need to be re-framed.

Much of life consists of small risks.  How we deal with them scientifically or politically, is not easy to decide.

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