Map of life expectancy at birth from Global Education Project.

Monday, August 18, 2014

GMO, continued

Okay, back to work. (I did a site visit on Friday and didn't feel like blogging over the weekend.) The GMO Deception is a collection of essays, mostly short, and mostly reprinted from the newsletter Gene Watch. They may date anywhere from the 1980s to the present, and they are in no particular chronological arrangement. This makes it quite difficult for the reader to develop a coherent understanding of the history, or even of the current state of affairs. One must pay close attention to the dates of the various contributions and then try to put things in order. It's always a chore and sometimes impossible. We'll read a passionate polemic decrying the regulatory regime of 1990 or worrying about gaps in knowledge in 1985, and then we're responsible for trying to find, somewhere else in the book, what has become of the situation.

This puts a substantial burden on the reviewer, because I'm not even sure I have everything straight and I've even had to do a bit of independent research to figure out what's going on. I also would recommend that Skyhorse hire a copy editor. There are some serious, fundamental howlers. These include Ralph's introduction which repeatedly refers to the herbicide Roundup as Roundup Ready, which is actually the brand name Monsanto's glyphosate resistant seeds. The error is reproduced in the introduction. Fig. 4 of the introduction is supposed to show the difference between GMO proponents' view of what happens when you introduce a single gene into an organism, and the reality. Unfortunately, both halves of the figure are identical, so there does not appear to be much difference. I won't go on because they didn't hire me to copy edit.

Anyway, Fig. 4 notwithstanding, the argument is sound. As even GMO proponent PZ Myers will not just admit, but enthusiastically affirm, gene effects are "pleiotropic." That means genes don't just do one thing. Some even code for more than one protein, by cutting and splicing at different places. But more generally, they interact with other genes, affect expression of other genes, and their products are typically involved in more than one developmental or biochemical process. So inserting one gene can cause a lot of changes in a plant beyond what is intended. (The process can also cause additional mutations.)

The regulatory regime for GMO foods in the U.S., as I understand it, requires only that manufacturers provide the FDA with a case that the single protein product of an inserted gene is safe to eat. This does not have to be based on any original animal or human research with the organism. In other words, you don't have to feed it to rats or monitor people who eat it, you just have to argue that Bt or whatever is harmless to humans. The editors and contributors to The GMO Deception don't think that's good enough, because the foodstuffs could differ in other ways from their non-modified precursors.

Well, maybe so, but others may find this a bit tendentious. After all, conventionally bred foods often differ in unintended ways from their ancestors. Conventionally bred tomatoes developed to be firmer and ripen more slowly for transport taste like cardboard. Mutations that alter proteins happen naturally all the time. Natural insect resistance, which is enhanced by intentional cross breeding, implies the expression of toxins. (This is a reason why many plants are toxic to humans, including the foliage of tomatoes and potatoes.)

It isn't clear, therefore, that genetic engineering presents any unique dangers to the food supply. We're already eating food that sacrifices nutrition for other properties, food allergies are already common, and completely natural foods contain carcinogens and other harmful substances as well as the good stuff. The fact is we have had 15 years of experience with most of the U.S. population consuming large amounts of GM corn and soybeans, and no sign of any harm except for the low quality diet that comes from eating a lot of processed corn products.

So, this is really the weakest part of the case. Yet it is the one that proponents focus on, as a handy straw man. The other objections are stronger, I think, but don't get as much attention in the political debate. It's easy to scare people with talk of "Frankenfoods," but that's a pretty speculative issue in my view and I find it tendentious. So I'll get to the more persuasive arguments in coming posts.

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