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Allergic to Science–Proteins and Allergens in Our Genetically Engineered Food

The views expressed are those of the author and are not necessarily those of Scientific American.


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A few weeks ago, the Union of Concerned Scientists released a policy paper entitled “The Healthy Farm: A Vision for U.S. Agriculture,” which is exactly what it sounds like.

A healthy farm practices sustainable agriculture, which means it must do three things well:

Productivity. A healthy farm produces food in abundance.

Economic viability. A healthy farm is a thriving business that provides a good living and fair working conditions to those who work on it, and contributes to a robust local and regional economy.

Environmental stewardship. A healthy farm maintains the fertility of the soil and the health of the surrounding landscape for future generations.

Current industrial farming practices in the US accomplish the first and second goals quite well, but these practices tend to be unsustainable and fail the “Environmental Stewardship” plank pretty miserably. The UCS’s concern about the dire state of our food system is well-founded, and I applaud their efforts to get out in front of the policy debate. There’s just one problem: they oppose using all of our technology to help combat this problem. Specifically, I’m talking about genetic engineering (GE) and genetically modified organisms (GMO).

Conversations of this sort inevitably devolve into ad hominem attacks on the GMO supporter’s credibility, so before going further, let me state clearly and for the record that I do not now, nor have I ever, nor do I ever plan to work for any company that produces GMOs. Neither have I ever received any form of compensation from any such company.

Nevertheless, I think that using genetic engineering to improve our crops can help move us towards more productive, healthier, and yes, more sustainable farming practices. Unfortunately, there’s a lot of misinformation standing in the way of public acceptance of this technology. Since I’m an immunologist, today I’m just going to address a single piece of that misinformation. From UCS:

[GE crops] may produce new allergens and toxins[...]

This statement is at best wildly misleading and at worse an all-out fabrication. For an organization dedicated to informing citizens about science, I’m a bit appalled that they got this one so wrong. But in order to explain why, I first need to explain a bit about genes, proteins and how these things interact with the immune system.

From Genes to Proteins

If you’re already well acquainted with the Central Dogma of molecular biology, feel free to skip ahead. For the rest of you, your memories of genetics may be a foggy recollection of a monk and his peas. But don’t worry, I’m not going to ask you to draw any punnett squares. The key thing to know is that your genetic information, encoded in your DNA, is a blueprint for the production of proteins*.

Proteins are the things that do work in the cell. They can do everything from providing structure and support, to communicating information between cells, to sensing the outside world, to catalyzing chemical reactions. Basically, if there’s a job to be done in a cell, it’s a protein that’s doing it. Proteins are fundamentally a linear sequence of small units called “amino acids.” In the same way that you can take a finite set of lego blocks and build almost any shape, evolution has selected for a finite set of about 20 amino acids, but these 20 blocks can be fit together in many different ways to make many different shapes of protein. Those different shapes determine the multitude of different functions that proteins have in a cell.

Because of the molecular biology revolution, we now have a pretty firm understanding of how a cell reads a particular sequence of nucleic acid (that’s the “NA” in DNA), and translates the code into a sequence of amino acids that becomes a protein of a certain shape and function. And one of the most amazing features of this process is that the language is the same regardless of the sort of cell you’re talking about, be it plant, bacteria, virus or mammal**. This is all very neat in theory, but it has profound consequences in practice.

For example, the insulin that diabetics need to stay alive is just a protein. Before genetic engineering, the vast majority of insulin was isolated from the blood of cows or pigs – these sources were not particularly reliable, and insulin from animals is not exactly the same as human insulin, leading to potential adverse reactions. In the 1980′s, scientists realized that they could use genetic engineering to make actual human insulin in bacteria. They isolated the DNA sequence code for the human version of the protein and inserted it into the genome of E. coli bacteria. The bacteria don’t know the difference between a human gene and a bacterial gene – it’s all just DNA! The bacteria read the code, and turned it into protein – the exact same protein that your own β-islet cells make in your own pancreas; it’s identical.

This is the same process used in genetic engineering of crops – moving a gene code for a protein or group of proteins from one organism into another. More on that later.

Proteins and Allergies

An allergy is essentially an immune response to something that’s not normally dangerous. Those pollen grains that are the source of so much misery don’t actually pose a threat, but your immune system may react as if it is. Your immune system makes particular antibodies called IgE that are able to bind some protein from the pollen. Those IgE antibodies coat the surface of mast cells, which are filled with a bunch of reactive molecules like histamines that make your immune system freak out. Mast cells evolved to combat parasitic worms and other infections, and when the immune response is directed appropriately, it’s a good defense – a little bit of inflammation is better than an infection.

When it’s directed against something abundant and harmless though, that’s when suffering ensues. Immune responses to all sorts of things have been reported, from the relatively common seasonal allergies to different types of pollen, to dust mites, to semen. Though these allergies can be quite unpleasant for the afflicted, but are usually not life threatening. Allergies to food, on the other hand, can be significantly more severe.

Because food allergies can lead to anaphylaxis and death, it’s perhaps understandable that people are worried about manipulation of food. But remember – allergies are a response to a particular protein. Our immune systems can distinguish between different proteins quite well, but is completely unaware of the source of that protein.

Case Studies on GMOs and Allergies

The Premise

Before getting started, let’s go back to the statement from UCS that I find so objectionable:

[GE crops] may produce new allergens and toxins [emphasis mine]

This is patently false – genetic engineering techniques allow us to precisely add genes of known structure and function to crops. It would in principle be possible to engineer corn that expresses anthrax toxin, or introduce peanut allergens into soybeans, but this would have to be by malicious intent of the scientists, not some accident. We know how genes work, and we know what kind of protein an individual gene will make.

Contrast this with a common tool of breeding in organic and non-GMO farming: Mutation Breeding. This is a technique whereby farmers expose seeds to large doses of radiation or chemical mutagens, and then selectively breed the seeds that have useful traits. This process may introduce hundreds or thousands of mutations into the genomes, and breeders cannot know where those mutations are. These mutations will change the shape and functions of proteins, and could, in principle produce new allergens. Despite the fact that this process is manipulating the genome, it’s not considered genetic engineering, and is allowed to be called organic.

Now, some examples of the most common types of GE crops.

Bt Corn

Different strains of the bacterium Bacillus thuringiensis (Bt) can produce proteins that are toxic to various invertebrates. These proteins, called “Cry toxins,” have been used in agriculture for almost 100 years – bacteria cultured in a certain way can be induced to create these proteins, and then sprayed onto crops. Certain types of insects are susceptible to eating these toxins and will die upon ingesting them. Bt Cry proteins are among the safest insecticides that can be used in agriculture, and there are many varieties that target different types of insect pests. Since Cry toxins are proteins, that means they are coded for by genes, and scientists realized that they could do away with the bacterium entirely.

In much the same way we can produce human insulin in bacteria, we can get corn (and other plants) to produce bacterial Cry proteins – and scientists did. The protein is produced predominantly in the leaves of the corn, and insects attempting to feed on the leaves ingest the Cry proteins at the same time and die. The protein isn’t expressed much in the corn kernels themselves, which is actually a problem for farmers wanting to use these crops to stave off insects that attack the ear, but it also means that humans enjoying that corn-on-the-cob are not going to be ingesting much either.

So, Cry proteins are safe to consume, they’re expressed in very low levels in the food we eat, and they’re sprayed on organic crops in huge quantities (and have been for almost a hundred years). There’s no reason to assume that Cry produced by corn is any different than Cry made by bacteria – it’s the same gene, so it’s the same protein.

Fishy Tomatoes

One of the horror stories often trotted out by GMO opponents is a tomato plant that was genetically engineered to resist frost. The winter flounder fish has “antifreeze” in its blood to allow it to survive in extremely cold waters. Scientists realized that antifreeze in plants would be incredibly useful – frost damage costs farmers hundreds of millions of dollars every year in lost crops or decreased productivity.

Now, I can understand why antifreeze in your food might sound scary, but this isn’t the stuff you put in your car. The antifreeze in the fish is just a protein called AFA3, and as you’ve probably gathered by now, that means it’s coded for by a gene. Unfortunately, when this gene was put into tomatoes, it didn’t actually provide much frost resistance, and these tomatoes were never brought to market, but I think this is an instructive example – if you could eat flounder without an allergic reaction, you could eat these tomatoes.

Potential for Harm

There are many examples of new GMO varieties that are using genes for proteins that don’t have a 100 year history like Bt, or aren’t usually ingested the way that flounder is. But there’s nothing magical about genetic engineering – it’s just about proteins. Most proteins are readily destroyed in our stomach and small intestine, broken down into their constituent amino acids and absorbed into our bloodstream, regardless of whether that protein comes from a cow or a tomato or a bacterium. Our digestive systems and our immune systems are oblivious to their origin.

It’s impossible to claim that there’s zero risk from using GMO technology in our food, and it’s worth testing the safety of anything new that we put into our mouths. Safety tests are done of course, but it would be impossible to eliminate all risk.

But a possibility of risk alone is not a valid reason to avoid a technology. As I mentioned above, mutation breeding is at least as likely to generate new allergens, if not more so. At least with GE, we know what genes are being changed, and we have better tools for testing the proteins that they code for. We’ve embraced many technologies that have risks, from microwave ovens to cell phones, and there’s more at stake here than quick meals or communication. In order to feed the billions of people on our planet without doing (more) irreparable harm to the environment, we need to be thinking about all of our options.

It’s also worth noting as Pamela Ronald did in this space two years ago:

There is broad scientific consensus that genetically engineered crops currently on the market are safe to eat. After 14 years of cultivation and a cumulative total of 2 billion acres planted, no adverse health or environmental effects have resulted from commercialization of genetically engineered crops.

Please note: I will not address comments here related to the myriad other complaints about GMOs – this is a post about allergens, but there are a number of other resources to check out:

GMOs do not cause cancer.
GMO’s have not driven Indian farmers to suicide
Herbicide resistant weeds are a problem, but not one unique to GMO
A Survey of Long Term GM Food Studies (collected papers)

—————

* Not all genes code for protein. There are also gene products like microRNAs, but these largely have an effect by regulating the expression of proteins.

** Not exactly the same, it turns out. Some species have slight modifications to the code, but it’s more like having different dialects rather than a different language.

Images: top: by author; Jessica Reuter; Dcastor; United States Department of Agriculture.

UPDATE (6/1/13): The UCS believes I have misrepresented their position here. They do not oppose GE technology per se, but (I’m paraphrasing here) think that it is under-regulated and that funding and research should be focused on other technologies. See comments below and also their website.

Kevin Bonham About the Author: Kevin Bonham is a Curriculum Fellow in the Microbiology and Immunobiology department at Harvard Medical school. He received his PhD from Harvard, where he studied how the cells of the immune system detect the presence of infectious microbes. Find him on Google+, Reddit. Follow on Twitter @Kevbonham.

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 45 Comments

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  1. 1. krohleder 9:39 am 05/30/2013

    GMO is a general concept and should be looked at by a case by case basis. However any manipulation, even by artificial selection, is most likely to cause some problem with at least a portion of the population (i.e. wheat/gluten). The problem with the industry is a trust issue. An informed consumer should have the right to know how their food is processed or what is in it. The fact that companies involved in the creation of GMO’s have leveraged and lobbied governments to block peoples right to transparency makes the industry as a whole seem shady from a consumers perspective. I just think that we should at least be able to label a product as containing GMO: is that too much to ask?

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  2. 2. julmaki 10:19 am 05/30/2013

    THANK YOU for this article!! It’s very frustrating to see how much people hate GMOs without understanding it in the least. It may well be that the companies employing it are evil and should be controlled/stopped, but that doesn’t have anything to do with the technology itself. Talk of getting rid of the technology completely just out of fear is not helping anyone.

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  3. 3. DavidManly 10:27 am 05/30/2013

    This is a great article – thank you for posting it on SciAm.
    I have been fascinated with allergies for a long time, ever since I suffered a mild anaphylactic attack after eating fish. My allergist diagnosed me with an allergy to some fish and seafood, but to be safe and avoid all fish and seafood.

    I am 100% for GMO foods, and I am glad that articles like this exist to dispel such bad information. However, I think labeling is key – for example, if I were to eat those “fishy tomatoes” but was unaware they had fish proteins, would I have a reaction (even a mild one)?

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  4. 4. nicholasjh1 11:36 am 05/30/2013

    I would agree. Monsanto has some extremely bad and shady practices, but it is not GMO specifically that is bad. I wish other industries would get this much scrutiny.

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  5. 5. mutualiti 11:44 am 05/30/2013

    You personally, Mr. Bonham, may not have received any contributions from any GMO producing companies, but Harvard, specifically Harvard Medical School, where I assume you have learned much of what you speak of here, receives many millions from Monsanto and has been entwined with Monsanto in ethically questionable association since at least 1975.

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  6. 6. Kevbonham 11:53 am 05/30/2013

    @ Krohleder – The issue with labeling is that a lot of people think that the misinformation around GMO will lead uninformed consumers to reject GMO-labeled food out of hand. However, I think I’m coming around to the arguments that it’s counterproductive to oppose labeling for exactly the reasons you mention. Actually, I might go further and say that companies ought to trumpet their GMO varieties… “Grown using X% less pesticide!!”

    @ julmaki – You’re welcome, and thank YOU!

    @ DavidManly – That’s an interesting point. The chances that your allergy is directed specifically against this protein is fairly low, especially because your allergy seems fairly general, and most fish don’t have this protein. That said, it’s the sort of thing that regulatory agencies should be paying attention to.

    On a separate but related note, there’s been some evidence recently that people with generalized allergies may in many cases be allergic to some contaminant, rather than to the food itself. So for instance, your “seafood” allergy may actually be an allergy to mercury or something like that – some food allergies may actually be to small amounts of insects that get pulled in during the processing. If that’s the case, just bringing the protein over from the fish would clearly not have the same effect.

    @ Nicolasjh1 – Yes. In many people’s minds there’s a 1:1 relationship between GMO and Monsanto, therefore any knock against Monsanto is a knock against GMO. Similarly, some see a 1:1 relationship between organic and sustainable, despite the fact that many Organic producers use incredibly unsustainable practices.

    The issues are way too nuanced for the simple frameworks that many people tend to utilize in these discussions.

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  7. 7. The Ethical Skeptic 11:56 am 05/30/2013

    Explaining why we are so smart that no science needs to be done, is rarely a strategy that produces sound results.

    Framing a legitimate scientific concern, as being the same or associated with a number of wild ridiculous claims from around the globe, is unethical.

    Premise: Allergen suspicions should not be studied
    Rationale: Here is how genes assemble proteins.
    Premise is not supported by Rationale.

    Claim: People who have concerns about allergen basis of GMO/hyrid foods, are stupid, ill informed and do not understand science. This is an unsubstantiated Claim.

    Nonetheless, population allergen response curves continue to hug very R^2-tightly the release of GMO and highly hybridized food crops – and have increased 3-fold since 1995.

    We want the science done, not insulting articles citing how stupid people are; how you are so smart that you do not need any data, and how no further science needs to be done.

    – TES

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  8. 8. Charles Ratliff 12:21 pm 05/30/2013

    The point about mutation breeding is well taken, and is probably not widely appreciated with respect to this issue. However, I am not (yet) convinced that the story is as simple as it’s laid out here: insert gene into genome -> gene encodes protein -> protein not a known allergen -> no effect on human allergies.

    As mentioned in the article, proteins have a multitude of different functions, most of which depend on an organism’s stage of development. One of these functions is regulating the expression of other proteins. Is it known, in all cases past, present and future, that a novel genomic insertion does not upregulate the production of allergens or toxins?

    The production and folding of proteins is complex. A single gene can produce a multitude of different proteins with different functions in different contexts, and the factors controlling protein expression are not well understood. A gene that produces one protein in one organism may produce a different set of splice variants in another organism, and each splice variant may be folded into another set of functionally different proteins. Is it known, in all cases past, present and future, that a protein inserted into a genome will never produce allergens or toxins as splice variants or folded forms?

    If the answer to either of these questions is no, then I must share the concerns of the UCS.

    Finally, the claim that no adverse health effects have resulted from GMO crops is debatable because the rates of allergy and disease have been rising in the US, without a proper explanation.

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  9. 9. Kevbonham 12:44 pm 05/30/2013

    @ Mutuality – C’mon, really? My salary comes from grants from the National Science Foundation (NSF) and National Institutes of Health (NIH). The funding for my lab comes from the NIH and Children’s Hospital Boston.

    My program taught me about the immune system, not about GMOs. Nothing from my Harvard education related to GMOs. The information I have written about here is based on an understanding of the immune system, and the basic biology of proteins and allergies.

    If you need to believe that the only reason anyone would say something nice about GMO is because they have some financial interest in doing so, you’re going to have to stretch pretty hard here.

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  10. 10. nihili 1:03 pm 05/30/2013

    It seems to me that this article misses three points.

    First, while I understand the contention that transferring genes from one organism to another does not, by itself, lead to the creation of new allergens, I don’t think we have to read the UCS worry in that way. If a gene is taken from an organism that is not typically ingested and transferred to an organism that is a common food, I think we can say that the transfer has “produced” a new allergen in the sense that people may now be allergic to a food that they weren’t before. If the focus is on the allergen as the food, and not the specific protein the UCS statement stands. Further, this is indeed the way most people understand allergies. We say that someone is allergic to peanuts, not that they are allergic to a specific protein found in peanuts. It is noteworthy that the current author sometimes speaks that way in the article.

    Second, I am not a microbiologist but if I understand correctly, proteins are chemically active. That is, a protein may change shape or combine with other chemicals to form a new substance. Thus introducing a protein into a new environment may result in the production of some further subject which may be a toxin or allergen. Please correct me if I’m wrong about this, but these sort of interaction effects seem to me to be at least a possible danger.

    Third, the present article considers only cases of gene transfer and not of gene creation. If a gene were engineered from scratch to encode some protein, then it seems more likely that such a protein might indeed be a new allergen. We might not be to that stage yet, but it’s worth considering the ramifications of such action before we do get there.

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  11. 11. Kevbonham 1:09 pm 05/30/2013

    @ TES- Thanks for the comment, but you’ve completely mischaracterized my piece.` I did not say “we are so smart that no science needs to be done,” nor that “allergen suspicions should not be studied,” nor “People who have concerns about allergen basis of GMO/hyrid foods, are stupid, ill informed and do not understand science.”

    In fact, I explicitly say “it’s worth testing the safety of anything new that we put into our mouths.” The thing is, safety tests *are* done, and have been done for decades. Does this mean we should dust off our hands and never look at the question again? Of course not, that’s not how science works, and no one is suggesting that.

    What I *am* suggesting is that we have no evidence to suggest that GMO’s have greater allergy risk, nor do we have any reason to assume that they might based on the underlying biology, and we have a lot of evidence suggesting that the ones on the market now are safe. Taken together, this suggests that being against GMO for fear of safety over allergens doesn’t make any sense.

    And no, a correlation with an increase in allergies that can also be found with cell phone use, internet access and plenty of other technologies is not evidence. See (http://www.venganza.org/about/open-letter/)

    @ Charles – Proteins in general may have a multitude of functions, but an individual protein tends to have a single function (no statements in biology are absolute, but this is generally true). Also, proteins like toxins and structural proteins tend to not have roles in regulation, though they may normally be regulated by many other factors.

    You’re right about splice forms, but those don’t tend to be an issue in cases like this. This was too complicated to get into the the article, but most genes in our genomes and the genomes of plants contain introns within the gene, and regulatory elements flanking the gene. These introns and regulatory elements can indeed have profound effects, and for some genes we don’t fully understand what these effects are. However, in genetic engineering, scientists tend to remove introns and regulatory elements and insert *only* the coding sequence for the protein, and use very well-defined promotors for expression.

    And we can also sequence the gene after it’s inserted, and look at the regions flanking it to make sure there’s nothing in the vicinity that might be problematic. Again, this is far more precise than mutation breeding.

    We could never say “This will never have risk,” but we can’t say that about anything. Am I 100% certain that my cell phone won’t give me brain cancer? No. Am I sure enough that I’ll carry it with me all day and put it up against my head? Absolutely. We adopt technology all the time, and we can never anticipate all the risks. It’s worth thinking about potential risks and working to minimize them, but not to the point of excluding a technology until we know it’s 100% safe. If we did that, we’d have no more technology than chimpanzees.

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  12. 12. Kevbonham 1:45 pm 05/30/2013

    @ Nihili – All excellent points.

    1) Yes, the way people understand allergies is different than the way scientists do, but that’s not how I read the UCS statement. Maybe I’m wrong, but the statement still seems misleading to me. In any case, I think their opposition to GMO w/r/t allergies is unfounded.

    2) I’m not sure exactly what you mean by “chemically reactive.” Some proteins are enzymes, and can catalyze chemical reactions, and some proteins are modified by other proteins. However, these functions are usually fairly specific with few “off target” effects. For instance, let’s say that humans and mice both have protein A. For the human version (hA), it’s job is to somehow modify hB. If we put that gene in mice, hA might or might not be able to modify the mouse B (sometimes genes are compatible across species, sometimes not), but it’s very unlikely to be able to modify mouse protein C.

    As for just base-reactivity in a chemically general sense, proteins are more likely to unfold or break down than anything else (from the point of view of the immune system, folded vs unfolded proteins aren’t handled very differently). In fact, as I mentioned, most proteins are broken down in your stomach and gut very quickly into their constituent parts.

    3) We don’t really know how to make proteins from scratch – they’re complicated beasts. We *do* know how to do some mixing and matching, and we could also introduce small mutations or insertions, and as you say, these might indeed be considered “new,” and could potentially contain allergens. This is not generally done now, but it may be done in the future.

    Such gene products should absolutely have a higher regulatory burden, and should have stricter standards of safety testing. I don’t think anyone would object to that, but it should be reasonable. I can’t think of any reason they should have more scrutiny than say, a novel drug compound.

    The FDA is imperfect of course, but we know how to test and regulate new things that are put into our bodies. I’m not asking (nor is anyone to my knowledge) for blanket acceptance of all GMOs. I’m only saying that we should use the technology to solve problems, not reject it outright due to fear and misunderstanding.

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  13. 13. Charles Ratliff 1:50 pm 05/30/2013

    Kevin, can you reference or expand upon the claim that a single protein generally has a single function? A general problem with studying knockout mice is that the single function that a scientist intends to study often profoundly effects other functions. A lot of transgenic mouse lines die before they can be studied. I’d guess that such mortality is always unexpected, because otherwise there would be no reason to make the mouse. A clean knockout of an intended function seems to be the exception, probably because many proteins have different roles in different cell types. Maybe it’s different with plants. If not, it seems reasonable to claim that GE crops may produce new allergens and toxins. The UCS put this claim in a reasonable context. I don’t think it’s appalling, wildly misleading or a fabrication.

    “While the risks of genetic engineering have sometimes been exaggerated or misrepresented, GE crops do have the potential to cause a variety of health problems and environmental impacts. For instance, they may produce new allergens and toxins, spread harmful traits to weeds and non-GE crops, or harm animals that consume them.”

    Further, while toxins and structural proteins may not typically be involved in regulation (I’m not an expert on this), you rightly point out that allergens are essentially an immune response to something that’s not normally dangerous. Thus it seems reasonable to assume that both common and novel allergens can assume regulatory roles.
    Also, to be clear, the UCS is not advocating that the technology be excluded. Just the opposite. You’re setting up a straw man. Here’s their full position statement:

    “Does UCS Have a Position On GE?
    Yes. We see that the technology has potential benefits, but we are critics of its commercial application and regulation to date. GE has proved valuable in some areas (as in the contained use of engineered bacteria in pharmaceutical development), and some GE applications could turn out to play a useful role in food production.
    However, its applications in agriculture so far have fallen short of expectations, and in some cases have caused serious problems. Rather than supporting a more sustainable agriculture and food system with broad societal benefits, the technology has been employed in ways that reinforce problematic industrial approaches to agriculture. Policy decisions about the use of GE have too often been driven by biotech industry PR campaigns, rather than by what science tells us about the most cost-effective ways to produce abundant food and preserve the health of our farmland.
    These are a few things policy makers should do to best serve the public interest:
    Expand research funding for public crop breeding programs, so that a broad range of non-GE as well as GE crop varieties will remain available.
    Expand public research funding and incentives to further develop and adopt agroecologically based farming systems.
    Take steps—such as changes in patent law—to facilitate independent scientific research on GE risks and benefits.
    Take a more rigorous, conservative approach to GE product approvals, so that products do not come to market until their risks and benefits are well understood.
    Support food labeling laws that require foods containing GE crops to be clearly identified as such, so that consumers can make informed decisions about buying GE products.”

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  14. 14. davidjalsberge 3:04 pm 05/30/2013

    “genetic engineering techniques allow us to precisely add genes of known structure and function to crops.” Seriously? No genes yet identified have only ONE function, nor are all of their functions known. This statement is patently FALSE.
    We also have NO way of knowing how those newly introduced genes will interact with other genes, either already present or during breeding, leaving open the possibility of completely unanticipated and impossible to foresee consequences.
    Monsanto, for example, can, and will be allowed to, genetically modify their crops to KILL any bees that land on them, presenting a danger to the bee population, and thereby, the food chain for all insects, animals, and Humans on the planet, without regard for the inevitable destruction of life on Earth. This flies in the face of any responsible genetic engineering, and should be stopped, not encouraged. It is as irresponsible as Earl Sinclair, of the ‘Dinosaurs’ series, bombing the volcanoes to make rain clouds, killing all the dinosaurs.

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  15. 15. Kevbonham 3:23 pm 05/30/2013

    @ Charles – Sure.

    Let me invent an example to illustrate my point. Let’s say there’s a protein that’s a receptor for some hormone. It’s “function” as I’ve been talking about it is to recognize the hormone, then activate some enzyme. The result of that enzyme activation may be different in different cell types or at different stages of development. For instance, a muscle cell responding to insulin is going to have a different response than a liver cell, even if both have the same insulin receptor. However, the insulin receptor is never going to recognize glucagon.

    Regulatory networks in cells can be extremely complicated, and if people were making GMOs with transcription factors or other regulatory factors, that could be that would be worth taking a harder look at. But that’s not what we’re talking about here.

    To your other point – you may be right that I’m being too hard on UCS. I should reiterate that I love that organization, and even considered applying for a job with them at one point. I respect most of what they do, I’m just worried that their position on this issue is hurting science literacy rather than helping it.

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  16. 16. dogctor 3:59 pm 05/30/2013

    Hi Kevin.

    This is a very shallow perspective on the subject.
    Lets talk about the known amino acid sequence differences between the inserted cry proteins, the active N-terminal domain and what we know about the linear and conformational epitopes of cry proteins, resulting from bombardment of the genome of plants. I am sure you are aware that there are scientific articles demonstrating mucosal and systemic immune response induced by Cry1Ac protein
    from Bacillus thuringiensis HD 73 in mice http://www.vkm.no/dav/0dea17091d.pdf

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  17. 17. Doctor B 4:21 pm 05/30/2013

    Thanks, Charles, for expanding this discussion to include the original statements by UCS, and thanks to the author for presenting his argument clearly. The author is only trying to address the potential for allergens, which is fine. But leaving out the rest of the GE multifaceted story leaves an impression of, “oh, all this concern is baseless.” I am glad to see many sides of this problem examined here.

    We also need to look at food reactions that are not classic IgE reactions. A person can develop food sensitivities that are not mediated via IgE. In my medical practice I am seeing many more of these reactions. Are they due to GE? No way to know since there is no way to know what the person is eating due to the banning of labeling. I don’t personally think they are driven by GE, but I do feel it is completely unethical to deprive the consumer of the ability to know what they are ingesting simply to avoid personal choice and the theoretical reduction in some corporation’s profit.

    My opposition to GE is not based on allergy. It is much more based on the wider environmental effects (pollen blows in the wind, those genes are now in your native grasses, etc.) and on the economics of farming. If anyone should be selected to play god in these matters, Monsanto would be near the bottom of the list of those we should trust.

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  18. 18. algernon 6:12 pm 05/30/2013

    The first three words in the title, “Allergic to Science”, set the tone of the article; they reflect a common myth among scientists: that people who resist genetically engineered seeds must be ignorant of science and biology, or that they are somehow anti-science. Labeling their opponents “anti-science” is also a political tactic employed by Pro-GMO activists – it’s purpose is to ridicule.

    GE scientists may believe that we “should” live in a technocracy, but the simple fact is we don’t. So if Biotechs try to push GE technology onto consumers without their consent, they naturally meet heavy resistance. It is the right of the American people to regulate technology, not the sole right of plant scientists or the biotech industry.

    Perhaps scientists’ biggest mistake lies in their active opposition to GMO Labeling. In speaking out against GMO Labels, they alienate themselves from the public at large, and they inadvertently cast a bad light on GE science and technology itself. In short, they lose the public trust, and that’s bad for GE science and the related technologies.

    GMO labels are not about the current state of the biological sciences – they are about long-standing social/political science. Apply the relevant science.

    Link to this
  19. 19. marclevesque 6:57 pm 05/30/2013

    Kevbonham -

    “To your other point – you may be right that I’m being too hard on UCS”

    You are not being ‘too hard’, you are misrepresenting their position. As others have mentioned, their position on GMO appears solid and based on science. http://www.ucsusa.org/food_and_agriculture/our-failing-food-system/genetic-engineering/

    “I’m just worried that their position on this issue is hurting science literacy rather than helping it”

    Considering the above, if I’m going to be worried, it is not about them.

    Link to this
  20. 20. Rich102 10:53 pm 05/30/2013

    “… Mutation Breeding. This is a technique whereby farmers expose seeds to large doses of radiation or chemical mutagens, and then selectively breed the seeds that have useful traits.”

    I suspect that if more people were aware that radiation and chemical mutagens were used in plant breeding, there would be a lot of opposition to mutation breeding, too. (I’m not sure how the warning label would be phrased, though. “Warning: nuclear radiation and chemicals known to produce mutations were used in the breeding of plants used in this product.”)

    Link to this
  21. 21. PlantSciGuy 12:54 am 05/31/2013

    “I suspect that if more people were aware that radiation and chemical mutagens were used in plant breeding, there would be a lot of opposition to mutation breeding, too.”

    And the scientific basis would be just as unfounded, based entirely on semantics like “radiation” and “mutagen”, rather than any actual effect on the plants or those who consume them. It’s just a technique, not an ingredient.

    I work in plant science, and that’s my central problem with GMO labeling. It’s not about hiding something; I think it’s great that people want to know what’s in the food they eat. But none of the label laws actually tell you *what’s in the food*. Which is what you want to know, right?

    Saying “may contain GMOs” provides almost no information about ingredients. The two main transgenics, the herbicide resistance gene (EPSPS) and the insect resistance gene (Cry) have nothing in common scientifically. Even if there were an allergy risk with either of them, it would say nothing about the allergy risk of the other, or any other GMOs. GM is just a technique, not an ingredient.

    A real, scientifically-grounded labeling law would also tell you which hybrid you’re consuming (there’s huge variation there), which pesticides were applied, and the toxicity of all those pesticides. Then you’d really know what you’re eating, including all the extra insecticide that must be sprayed on non-GMO crops–including organic crops.

    Of course the burden of all that labeling would be tremendous, and (as long as agencies like the EPA are doing their job) completely unnecessary. Still, I could get behind that kind of initiative, but I would want it to be voluntary just like organic or Kosher labeling. That way people who don’t want to pay the extra cost have the choice not to.

    Link to this
  22. 22. Owl905 3:23 am 05/31/2013

    After reading the article and the comments, I’m more concerned about GMO risks than before reading.
    The Union statement about what may be produced is challenged at a narrow definition level – and flunks at a broader street-level interpretation.
    As nihili itemized, and others supplemented, taking elements from the relatively uneaten (flounder), and adding to the ubiquitous (tomato), is a good example of a gross violation of the precautionary principle.
    The article could take a better approach than tattooing objections with a credentials distraction (a weak-shot about “inevitably devolve”).
    And the objection to the Union’s concern as “patently false” isn’t refuted; it even provides one avenue (malicious intent) for introduction. The subject needs to address the elephant in the room: profit-hunger leads to rose-colored optimism. That’s not a fiction – Bayer’s tilted testing of neonicotinoids may be imbedded in the resulting CCD problem. The article reads like a setup for a parallel case – example, Roundup-resistance response.

    Link to this
  23. 23. marclevesque 9:24 am 05/31/2013

    On labeling GMOs :
    “unlike most other developed countries—such as the 15 nations in the European Union, Japan, Australia, Brazil, Russia and China—the U.S. has no laws requiring labeling of GE foods. Yet polls have repeatedly shown that the overwhelming majority of Americans—over 90% in most polls—believe GE foods should be labeled”

    Why no GMO labeling in US and Canada :
    “the Federal Food, Drug, and Cosmetic Act requires the FDA to prevent consumer deception by clarifying that a food label is misleading if it omits significant, “material” information, the FDA issued a policy statement in 1992 that limited what it considered “material” to only changes in food that could be noted by taste, smell or other senses. Since GE foods can’t be “sensed” in this way, FDA declared them to be “substantially equivalent” to conventionally produced foods, and no labeling was required. It was, and remains, a political decision, not a scientific one”

    http://www.centerforfoodsafety.org/issues/976/ge-food-labeling/about-ge-labeling

    Link to this
  24. 24. Kevbonham 11:34 am 05/31/2013

    @ Doctor B – Fair points. Unfortunately, multi-faceted conversations about GMO tend to spiral off into crazy town. I thought it best to address a single point at a time.

    @ Algernon – I apologize for setting a belligerent tone, hopefully the comments section has ameliorated that somewhat. I don’t disagree with anything you’ve said on the general state of the GMO debate. The trouble is, having a nuanced discussion about GMO policy, patents etc is impossible while we’re still having the science-free conversations about things like new allergens or toxins.

    @ PlantSciGuy – Yes, exactly.

    Link to this
  25. 25. tlambert 11:37 am 05/31/2013

    “…when RBL2H3 cells were reacted with Cry1Aa digests obtained by SGF digestion at pH2 and pH4, the amount of histamine release significantly increased. Cry1Ab digests also induced histamine release but did not seem to depend on the digestion pH.”

    A Comparative Study of Histamine Release from Rat Mast Cells by Cry1Aa, Cry1Ab and Cry1Ac Fragmented with Simulated Gastric Fluid (SGF).
    Mayumi Ohno, Miho Suganuma, Youko Egawa, Kazuya Tomimoto, Takashi Hara, Tohru Hayakawa, and Hidetaka Hori*
    Graduate School of Science and Technology, Niigata University, Niigata, Japan, 950-2181.
    http://www.erudit.org/livre/pacrim/2005/000213co.pdf

    Link to this
  26. 26. Kevbonham 1:23 pm 05/31/2013

    @ tlambert – I’ve worked with mast cells in culture before. If you look at them the wrong way they’ll degranulate. Need a control where something like albumin was also digested in the same procedure and see that there’s no effect.

    Link to this
  27. 27. BrainGym 1:26 pm 05/31/2013

    I was hoping that with your experience you could explain why during extensive allergy testing of my daughter’s food intolerances she immediately got hives from GMO corn and not non-GMO corn? My Harvard educated immunologist agrees labeling of food would be a measure that would keep her safe.

    Link to this
  28. 28. PlantSciGuy 4:35 pm 05/31/2013

    BrainGym, what you may not realize is that the transgene is actually bred into multiple lines of corn, and there is way more variation between transgene, than there just between GMO and non-GMO. Other than a direct diagnostic test for antibodies to the transgenic, the best way to tell if the transgene is the problem is to make sure you’re comparing the same hybrid of corn.

    If she is sensitive to a certain hybrid, then full labeling, and not just GMO vs non GMO, might help your daughter. If you suspect it is the transgene, can’t you just buy organic? Voluntary labeling already exists.

    Link to this
  29. 29. blubasia 7:23 pm 05/31/2013

    I think Nihili gets it right. You are probably making a narrow scientific point, but to the general reader, it seems like you are getting off on a technicality. GMO may not cause the creation of a new allergen, per se; but there is, indeed, something new going on, i.e., the introduction of an allergen into a heretofore “safe” food, for example, a fish protein in a tomato. So, given the terms of FALCPA, will it be required that the “fish-tomato” be labeled as containing a fish ingredient, and corn cobs labeled as containing soy? How will that reliably be done? With those little sticky produce labels that can easily fall off or be peeled off, much to the danger of the consumer with anaphylaxis to fish or soy? And what about the extreme risk of cross-contamination of an otherwise ordinary tomato crop by seeds of fish-tomatoes in the field, the risk of mix-up of regular tomatoes with actual fish-tomatoes on grocery shelves, etc.? It seems GMO could be a nightmare for a food-allergic consumer.

    Link to this
  30. 30. Rich102 9:57 pm 05/31/2013

    PlantSciGuy: I’m not clear whether you recognized the sarcasm in my post (and were just expanding from there) or it you really think I want warning labels like that. (I thought I’d made it outrageous enough to be recognized for what it was.)

    Link to this
  31. 31. greenhome123 3:41 pm 06/1/2013

    I am totally in favor of GMOs if they produce useful things like drought tolerant crops, or crops which are resistant to disease. But, genetically altering a crop to be resistant to RoundUp, or other weed killers, so millions of acres of farmland can be drenched in herbicide is not my idea of sustainable, because it destroys the fertility of the soil. The active ingredient in the herbicide is not as bad for the soil as the added surfactant. In regards to USC saying GMOs may cause allergies or toxins, I believe it is as the author says, “in principle possible”. So, I do not understand his problem with USC saying “GMOs MAY cause allergies or toxins”. They said MAY cause….not DOES cause.

    Link to this
  32. 32. PlantSciGuy 8:34 pm 06/1/2013

    @Rich102: Sorry if it wasn’t clear, I was just carrying your point out further.

    And a correction to my last post, I meant

    “and there is way more variation between *breed*, than between GMO and non-GMO.”

    Link to this
  33. 33. tlambert 4:03 am 06/2/2013

    @ Kevbonham: I would agree with you for people with a perfectly functioning digestive system; however, there are a number of conditions, including pernicious anemia, which can cause abnormal digestion. In those cases, the breakdown of Cry1Aa does not proceed as you’d expect, regardless of the presence of albumin. Similar issues surface in cases of advanced H. Pylori infections.

    Like the original errors in Gray’s anatomy that resulted from too small a sample size classifying some rarer anatomical variations as normal, I don’t think it’s possible to safely say what metabolic pathways will or will not be completely effective.

    Link to this
  34. 34. Kevbonham 12:55 pm 06/2/2013

    @ Blubasia and tlambert – in those cases, as PlantSciGuy has been advocating, the solution is voluntary labeling of products that do not contain the offending products. Consumers that have strict digestive requirements are already able to buy vegan, kosher, gluten-free, soy-free, organic products.

    As gluten sensitivity has been on the rise, does it make sense to make every product that contains gluten have a label that says “contains gluten?” No, it’s far more cost-effective to have gluten-free products voluntarily labeled as such.

    If you want to enjoy non-GMO food, it’s easy – just buy organic.

    Link to this
  35. 35. marclevesque 7:30 pm 06/2/2013

    @Kevbonham

    “The UCS believes I have misrepresented their position here. They do not oppose GE technology per se, but (I’m paraphrasing here) think that it is under-regulated and that funding and research should be focused on other technologies”

    Paraphrase of an excerpt from the UCS website :

    GE has proved valuable in many areas. But so far its applications in agriculture has fallen far short of expectations, and in some cases has caused serious problems. Rather than supporting a more sustainable agriculture and food system with broad societal benefits, the technology has been employed in ways that reinforce problematic industrial approaches to agriculture. Policy decisions about the use of GE have too often been driven by biotech industry PR campaigns, rather than by what science tells us about the most cost-effective ways to produce abundant food and preserve the health of our farmland.

    Link to this
  36. 36. Madeleine Love 8:22 pm 06/3/2013

    It is shameful of the GM Industry to allow this poor young man to expose himself so badly by parroting their pervasive GM myths. Unless he is committed to a life of industry PR rather than science they have done a terrible thing to his career. Shame!

    Link to this
  37. 37. karl 11:11 am 06/4/2013

    I liked this article pretty much, rationale is that if you eat a GMO lettuce and tomato salad you are eating lettuce, tomato, some bacteria and some fish, if you eat an “organic” (because inorganic lettuce would be what, asbestos?) salad you eat bacteria, lettuce, tomato and you’ll have fish later anyway!.
    The other mutation process is like using a shotgun, get a bunch of near misses and breed the ones that seem closer to work, (ok, one of them is actually the plant from the little shop of horrors, chewing an illegal worker at your farm but, hey it saves a lot on wages!)

    On the economics side, all questions and troubles, please adress your gentech company for their cuttrhoat capitalist strategies.

    Link to this
  38. 38. mitshoo 6:24 pm 06/4/2013

    Everything said above is great, really good comments everyone. But can we also keep in mind that the GMO industry is not the Second Coming of Christ, returned to save mankind and farming? Can we remember it’s about patenting genes and making money? I think more disturbing than genetic modification, which is a weird enough concept, is the idea that someone can own gene sequences. That’s pretty messed up. So before we start mindlessly praising any technology that gives us this fuzzy feeling that we are finally in “the future” and before we start mindlessly bowing to whoever makes this technology, let’s just remember the political/power implications of letting someone else own what we grow. I feel like there is a word for that…feudalism, maybe? Probably an imperfect fit…

    Link to this
  39. 39. rknight101 11:47 pm 06/5/2013

    @Kevbonham, for someone who isn’t working for the industry, you did a great job of covering their talking points.

    Here are some study based GMO facts:
    GMO Myths and Truths
    An evidence-based examination of the claims made for the safety and efficacy of genetically modified crops
    Version 1.3
    by
    Michael Antoniou
    Claire Robinson
    John Fagan:

    Genetic engineering is completely different from natural breeding and entails different risks. The genetic engineering and associated tissue culture processes are imprecise and
    highly mutagenic, leading to unpredictable changes in the DNA, proteins, and biochemical composition of the resulting GM crop that can lead to unexpected toxic or allergenic effects and nutritional disturbances.

    Foods produced by cisgenic or intragenic methods are as hazardous as any other GM crop.

    It is misleading to compare GM with radiation-induced mutation breeding and to conclude that, as crops bred by the latter method are not tested for safety or regulated, neither should GM crops be tested or regulated. Radiation-induced mutation breeding is potentially even more mutagenic than GM, and at least as destructive to gene expression, and crops produced by this method should be regulated at least as strictly as GM crops.

    GM Bt insecticidal crops pose hazards to people and animals that eat them.

    Bt toxin protein may not be broken down harmlessly in the digestive tract.

    No thorough allergenicity testing is conducted on GM foods.

    It is unnecessary to take risks with GM when conventional breeding – assisted by safe modern gene mapping technologies – is capable of meeting our crop breeding needs.

    http://www.nongmoproject.org/wp-content/uploads/2010/08/GMO_Myths_and_Truths_1.31.pdf

    Link to this
  40. 40. larkalt 9:43 am 06/6/2013

    What is disturbing to me about GMO’s is that delayed-reaction food allergies are not well understood.
    People with delayed allergies to corn, for example, are worried about corn allergens being in foods that appear to have nothing to do with corn.
    Classical corn allergies are rare, but delayed corn allergies are perhaps much more common. Reaction takes several hours to come on, it’s a foggy state that lasts several days, perhaps with itching, irritability etc. It’s not clear that whatever proteins that cause delayed corn allergies are known as allergens by science and regulators.
    Problems can occur with regular breeding also. The wheat amylase trypsin inhibitors are allergens and also cause insect resistance, so wheat was bred to have a lot more of them – perhaps causing huge health problems.
    GMO’s may well need to be tested more than they are – an issue you didn’t address. Of course Monsanto etc. wish to get by with as little safety testing as they can.
    There seems to be an unconscious belief operating that “it’s food, food is safe, very little safety testing is needed”.
    Not true! Immune reactions to food can have profound effects on people’s health.

    Link to this
  41. 41. Nisslbody 11:23 am 08/10/2013

    I am not at all anti-GMO, but I do have some concerns about issues like pollen drift, especially with Terminator crops and trans-species pollination. I also have concerns about unintended consequences such as those that may occur when we take an effective natural pesticide like BT that normally resides in the soil, and cause crops to express it in their aerial parts, pollen, and fruit. What are your thoughts about these issues, and have they changed at all since you wrote this article?

    Link to this
  42. 42. Nisslbody 11:27 am 08/10/2013

    Pardon me, I said “trans-species pollination” (which does occur, technically, sort of, but is an inaccurate term) when what I meant was “trans-species genetic transfer”.

    Link to this
  43. 43. rmacfarl 4:03 am 09/13/2013

    http://www.abc.net.au/radionational/programs/backgroundbriefing/2013-09-15/4950990

    Lynas is a respected environmentalist, and a strong campaigner on climate change who’s written award-winning books. What irked him was the slow realisation that his passionately held views on GM were inconsistent with his reliance on evidence-based science when arguing his position on human-induced climate change. When it came to GM, he admits, he actively ignored the weight of evidence in favour of biotechnology.

    The argument he puts is that an estimated three trillion meals containing food derived from GM-bred plants have been eaten in 29 countries over 15 years without one single substantiated case of harm. ‘You are more likely,’ he quips, ‘to get hit by an asteroid than to get hurt by GM food.’

    The project’s on track to produce enriched bananas ready for human eating trials by next year. But not if some of the NGOs in Uganda have their way. Lynas has just returned from a visit there with some hair-raising tales of treachery by anti GM activists.

    He says he’s heard stories from local MPs who have had activists going into their Muslim constituencies telling people that the scientists are putting pig genes into bananas—the bio-fortified and the bacteria-resistant bananas—which you wouldn’t be allowed to eat as a Muslim.

    ‘Literally, people have been going crazy about this,’ Lynas reports. ‘There’s almost been violence breaking out. So, the anti-GM activists have stooped so low as to cause religious violence in order to stop this technology.’

    Link to this
  44. 44. vmaldia 8:53 am 05/11/2014

    \\ Environmental stewardship. A healthy farm maintains the fertility of the soil and the health of the surrounding landscape for future generations.

    Current industrial farming practices in the US accomplish the first and second goals quite well, but these practices tend to be unsustainable and fail the “Environmental Stewardship” plank pretty miserably\\

    http://iapps2010.wordpress.com/2014/04/16/irri-150th-harvest-from-worlds-longest-running-continuous-rice-experiment/

    Gee, this long term experiment uses normal industrial agricultural techniques : using insectdicide and artificial fertilizer and yet after 150 plantings the soil is still fertile

    Link to this
  45. 45. vmaldia 9:06 am 05/11/2014

    \\ The genetic engineering and associated tissue culture processes are imprecise and
    highly mutagenic, leading to unpredictable changes in the DNA, \\

    is that still true? AFAIK new techniques like CRISPR are precise. I’m no expert but as I understand it CRISPR works by pairing a RNA antisense strand to a DNA cutting enzyme. Since the RNA antisense strand will only bind to a specific stretch of DNA the location in the genome where genes are removed/added can be controlled with precision

    Link to this

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