Saturday, May 18, 2013

GMO - part2 - why we fear it

The Fear and Wonder of a Chimera
We feared them - the chimeras or hybrids. In ancient times people were told about hybrid animals: the horse that was half human- the torso and head of a man with the body of a horse, the man that had the head of a dog, the horse that had wings. Some have familiar names, like Pan- who had the hind quarter of a goat and horns of a goat but face of a man.

Ancients saw these either as  an abomination, an unholy thing made from cross breeding and to be cursed; but others saw them as a sense of wonder. The Centaur, half horse half human that were great warriors.

Even in the bible, when the "end times" come the description of the feet of the bear and the mouth of the lion and the body of a leopard.

The fear of chimeras is throughout all human mythology - but now, those chimeras are no longer a myth - they are real. Humans  can produce a chimera, or hybrid,  from the DNA of different species, making crops and animals that are modified to produce a chimera. Are those same fears, same sense of wonder a part of the human collective conscious? Does that explain the debate about genetically modified organisms?  
Since the ancient times the fear of chimeras has been a mix of wonder and horror. Now, with DNA technology we can make them - sort of.
 What's missing is science education, critical thinking, and the ability to talk the same language

Perhaps it is my background in genetic engineering that makes the idea of genetic engineering interesting, and not scary. The knowledge that humans have manipulated genes in plants for at least 11,000 years gives some perspective. Genetically Modified Organisms (GMO) that are plants are neither the Frankenstein chimera that some suggest, nor are they the magic bullet for the common problems of feeding the world and saving the environment.

 They are but one tool and sometimes that tool has  failed. What bothered me greatly as I researched the issue, was that the people who were anti-GMO did not even speak the same language as those who were proponents of GMO. The logical fallacies in arguments were on both sides: appeal to antiquity, appeal to authority, and ad hominem being the most common. One fact was alarmingly clear: people will say anything, put up any photograph, repeat falsehoods because they think their concern about GMO are valid.

 This does not advance a rational discussion, this does not help advance the common quest we all would seek to find a safe way to feed the planet.  It also pointed out that critical thinking is not taught, and science education is lacking. There are rational concerns about some GMO, but those discussions become lost when histrionics replaces a sense of history, when the discussion is not about science but about fear. On the other side, the proponents of GMO, are often dismissive - partly because they lump those who express legitimate concern for GMO with those who are clearly irrational , and partly because they become forced into a position to support science.

Thirty Years of Molecular Engineering Plants

The first genetically modified plants from modern molecular engineering was reported 30 years ago. In 1983 a gene, made from DNA not belonging to the plant, was transferred into a plant and this technical feat and outcome reported in the journal Nature.  

But genetic modification of  plants by humans has been going on for thousands of years. While at times we will specifically use "molecular engineering" for the modern technology of  modifying existing DNA or inserting new DNA into plants, for most we will use genetically modified (GM) crops to mean those crops which have specifically had their DNA modified by molecular technology. 

It has been 35 years since Dr Roizman first showed how the DNA coding for a protein from one species (a chicken) could be put it into the DNA of a virus (Herpes).  That use of a virus to host a DNA led to the idea that a plant virus could be used to insert DNA into a plant. DNA codes for all the proteins of the plant, much like humans. The techniques used then are now considered as outdated as using a floppy disc - and in fact, the ability to molecular engineer DNA can probably be done in a garage.

Ethics and concerns about our chimera (Herpes -Chicken) the concerns about molecular engineering were not yet articulated.  At that time it was a breakthrough to prove we could move a gene from one bit of DNA to another, and have that new organism make the chicken protein. Prior to that it was theoretically possible, but never proven. Once proven, did we open Pandora's box or did we find the stairs to heaven?

  Would you inject it? 

Most who are concerned about GMO worry about our foods.  But imagine injecting an ingredient that has been extracted from a genetically modified organism into your body and other ingredients labeled like this-  

It turns out that people inject this everyday.  Did you know that people not only inject this everyday but it keeps them alive? It is called insulin.

The rest of the carton

This has been tested and highly regulated. So when worried about the food supply, do not forget that GMO also applies to bacteria and yeast that produce proteins that some need daily to keep alive and healthy.

Would you choose to buy food made from a GMO and should we Label it

For some this is a controversy. The insulin above is clearly labeled, it says what it is- where it is from, and what else is in it. The question is- how do you label corn - because corn is a new plant, it wasn't even around a few thousand years ago. Although most who wish food to be labeled intend those foods that contain proteins from another species. The insulin which the vast majority of Americans take, come from DNA from humans, but grown in yeast or bacteria.

The anti-label seem to be the industry who makes the GMO and they contend that most scientists, and the FDA find the food is safe, so why add an additional label to the product. The counter argument: should not people decide for themselves if they wish to have it.  In a way this is an esoteric argument: I have a hard time getting my patients to read food labels- and most Americans do not read labels. But there is nothing wrong with a label, there is nothing wrong with letting people decide what they wish to eat.

Most of the corn and soy grown in the US are genetically modified. There has been no immediate ill effect, and yet, some would argue that trans-fats, once considered to be good fat, were not discovered to have an ill effect until years later. They undergo testing - but that does not mean how a product is made should exempt it from a label.

The industry groups  says that some people would shun those foods, wanting non GMO foods. The pro-label says, yes, that is the idea. Letting the market place work is probably scary for the industry's makers but educating the public about GMO is not bad. 

The fear of industry that they would have to change or educate the public is paternalistic, and reminds me of the argument at the beginning of the enlightenment that churches didn't want their flock to learn to read lest they question authority.

What doesn't help is this: we have lost science journalism. Finding a journalist who can look critically at a paper and present the information in a detached way is gone. Most journalists now, even from The New York Times, are more entertainment-style journalists - flashing a headline, quick quotes from a pool of scientists or physicians, and off with a story. But GMO are too important to leave to such journalists, GMOs are here to stay, but need to have a place where rational discussion can happen from those who are concerned.  

The goal of farming production, is to use less fertilizer, less herbicides, less pesticides, and less water. The hard way to do genetic engineering is what the Mayans did, by cross-breeding and selecting plants. Over a few thousand years they took one plant, and made it into another species - corn. Modern genetics shortens this cycle - instead of cross breeding, the proteins in the plant are discovered and expressed more.

  The Promise of Molecular Engineering plants: 

The promise of molecular engineering is based upon what Genetic engineering already showed: the ability to make crops that (a) grow faster (b) resistent to pests (c) resistant to weeds. We would add that the new goal of molecular engineered plants would be environmentally friendly, at the least, and helpful to the environment at the most.  The ability of plants to convert carbon dioxide to oxygen may be one of the major ways to diminish green-house gases.

 In GMO farms there are less pesticides and less herbicides used. That doesn't mean it will always be this way. What GMO has done is improve the yields of crops, it has decreased the use of some toxic chemicals on the land, it has provided a mechanism to improve nutrition, and decreased the use of water. But that can change.

In an effort to find the truth about GMO - and avoid the hyperbole on both sides, I did discover some rather disturbing myths out there. One is a photograph that shows a picture of two corn cobs, one eaten, the other not. One labeled GMO corn, the other not - it is a doctored photograph.  To think a squirrel would have more taste or better taste than a human is not only biologically incorrect, it is laughable. The person who put this up is a well known anti-GMO activist. This does nothing to further discussion, but is propaganda to increase fear.
This photo widely used on the internet is an experiment that has not been reproduced. Probably one corn was treated with something to make the animals like it better, or perhaps no animals in the wild ate it- since the corn is left on the platform, and it is unlikely corn would be removed from the husk and left by any animal

  Here are some things that are on the internet that are myths - the tomato fish:

They have a tomato which has a gene inserted in it from arctic fish so that the tomato will survive cold weather. This is not true. The cartoon 0f a chimera fish/tomato was a rallying point for some anti-GMO sentiment, but it turns out that such a product is not to be found on any market shelf.

 I understand one of the main issues was vegetarians who were concerned that having a protein from an animal in a plant would violate their vegetarianism (ok, that one made me scratch my head also). 

It was an interesting idea, and no one has any idea how far these experiments went, but biology would tell you that a frost resistant fish probably isn't going to be helping a tomato. When the company who was working on the project was approached they noted that the experiment was a dismal failure. Then again- think about it: a fish has a heart and blood vessels and is pumping things - a tomato, well, doesn't. Still the idea of transferring proteins from one species to another, much as we did 35 years ago, raises concerns. The problem is that there is too much hyperbole in the debate and the discussion.

  German Cows Die after Eating GM modified Corn:

It is true that Syngenta(the supplier of GM corn) reimbursed the farmers for the loss of cows, and that the cows did eat the corn that had been genetically modified.  The investigation of the cow deaths concluded that the GM corn was not the cause of death. In addition, there were extensive feeding studies of that GM corn (Bt 176) which were published in peer review journals and there was no adverse effect. Further, that corn had been planted for a number of years without adverse effect in those fields.  Turns out the cows probably died of botulism.

Did Rats get tumors because of GMO corn

Rats developed tumors when eating GMO corn - not really. This was a paper that was published- and it had a lot of flaws: (a) These types of rats all develop tumors when they get old (b) severe statistical issues, with a small control group (c) No basic statistical significance (d) No dose response curve. The rats were fed unlimited amount of corn - if you feed this type of rat unlimited food they develop cancer.  Bad study, highly repeated in the internet - not repeated by anyone. Here is a response printed in full to that article: Seralini et al. (2012) claim to have found evidence for the long term toxicity of roundup-tolerant genetically modified maize (GMM). Using one-tailed Fishers exact test we show that there is no statistically significant increase in mortality rates or the number of tumors in rats fed GMM compared to control groups in the original data. Seralini et al. state that “In females, all treated groups died 2–3 times more than controls”. As follows from the figures presented: 2 female rats out of 10 died before the mean survival time in the control group, compared to 29 out of 60 in the six GMM fed groups. This difference is not statistically significant (P = 0.09). Note that this P-value requires a further correction for multiple comparisons due to two groups of rats (of different sexes) being independently analyzed. Among males 3 rats out of 10 died prematurely in the control group, compared to 19 out of 60 rats in the six GMM fed groups. This difference is statistically not significant (P = 0.615). Ironically if we forget about the importance of statistical significance and present the data in a manner used by Seralini et al., we could say that “In males, groups with 22% and 33% GMM in their diet died 3 times less than controls”, however this was not reported. This difference is also statistically not significant (P = 0.291 for each comparison). Seralini et al. state that “In treated males, liver congestions and necrosis were 2.5–5.5 times higher” and that “Females developed large mammary tumors almost always more often than and before controls”. Two male rats out of 10 had liver pathologies in the control group, compared to 30 out of 60 GMM fed male rats. Five female rats out of 10 developed mammary tumors in the control group, compared to 44 out of 60 GMM fed female rats. These differences are not statistically significant (P = 0.076 and P = 0.133). Note that this analysis should be done with care: over 30 different organs were analyzed in this study, but data on only a few was presented, giving rise to the statistical problem of multiple comparisons that was not addressed in the article. However, even despite this problem, all reported differences between the number of rats with specific organ pathologies in control and GMM fed rats are not statistically significant. It is also worth noting that tumors are frequent in Sprague–Dawley Rats: a spontaneous tumor incidence of 45% was previously recorded during a 1.5 year period (Prejean et al., 1973). The images of GMM fed rats with large tumors presented by Seralini et al. are misleading as they imply that such tumors do not normally occur or occur less frequently in untreated rats. Such tumors may occur in rats that are not fed GMM and Seralini et al. provide no statistical evidence that the incidence of tumors in general or any specific kind of tumor is increased in GMM fed rats. The random nature of the observed differences between control and GMM fed rats in the study is consistent with the lack of dose-dependent relationships between the amount of GMM in the diet and the supposed toxic effects of GMM. A news article published in Nature stated that “The controversy over the findings is likely to be settled only after detailed analysis of the paper and its data, and replication of the experiments” (Butler, 2012). Analysis of the data suggests that no statistically significant findings of GMM toxicity were presented in the first place.

  Did sheep die from eating cotton with Bt?

 In almost every anti-GMO site I visited this was repeated over and over again, in spite of the  evidence against it. A group of sheep who died after grazing on a field of cotton. The accusation was that the sheep died from some unexplained poison - and that part is true. Sheep have been dying from toxins in cotton fields long before Bt cotton, and with the same lesions described  the anti-GMO groups ascribe to GMO.  In all cases the veterinarians describe that the sheep died of a toxin, probably pesticides used. Veterinarians  could not rule out nitrate or gossypol (a natural toxic ingredient of cotton plants) as toxic agents.  When Bt was fed to laboratory animals there were no deaths. Less pesticides are used on Bt Cotton modified plants, the total use of pesticides in the 10 million farmers who use Bt cotton has gone down.  

  DISCLOSURE: I am not, nor ever have received funding support from Monsanto, or any corporation making or considering GMO. The funding received for the original research done with molecular engineering came from a grant from the National  Institutes of Health, and not associated with any industry.  Nor have I been paid any stipend, nor received any accommodation from such industries. Nor am I seeking such

. FUTURE BLOGS: Allergies and GMO - the real story GMO and the Third World  

  (1) Areawide Suppression of European Corn Borer with Bt Maize Reaps Savings to Non-Bt Maize Growers W. D. Hutchison, E. C. Burkness, P. D. Mitchell, R. D. Moon, T. W. Leslie, S. J. Fleischer, M. Abrahamson, K. L. Hamilton, K. L. Steffey, M. E. Gray, R. L. Hellmich, L. V. Kaster, T. E. Hunt, R. J. Wright, K. Pecinovsky, T. L. Rabaey, B. R. Flood, E. S. Raun Science 8 October 2010: vol. 330 no. 6001 pp. 222-225 PMID: 20929774

 (2) A 2-year field study shows little evidence that the long-term planting of transgenic insect-resistant cotton affects the community structure of soil nematodes. Li X, Liu B. PLoS One. 2013 Apr 16;8(4):e61670. doi: 10.1371/journal.pone.0061670. Print 2013. PMID: 23613899

 (3)Beever D and Kemp C (2000). Safety issues associated with the DNA in animal feed derived from genetically modified crops. A review of scientific and regulatory procedures. Nutritional Abstract Reviews Series B: Livestock Feeds and Feeding 70:175–182.

 (4)Flachowsky G, Chesson A, and Aulrich K (2005). Animal nutritional with feeds from genetically modiļ¬ed plants. Archives of Animal Nutrition 59, 1–40. (

5)Flachowsky G, Aulrich K, Bohme H, and Halle I (2007). Studies on feeds from genetically modified plants (GMP) – Contributions to nutritional and safety assessment. Animal Feed Science and Technology. 133: 2-30.

 (6)Goldstein DA, Tinland B, Gilbertson LA, Staub JM, Bannon GA, Goodman, RE, McCoy, RL, Silvanovich A (2005). Human safety and genetically modified plants: a review of antibiotic resistance markers and future transformation selection technologies. Journal of Applied Microbiology 99:7–23.

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