Golden Rice: Of Good Intentions, Insertional Mutants, Human Error, and the Need for Better Regulation of GMOs

After learning that the genetically engineered (GE) Golden Rice “event” being bred into varieties of rice favored by Indian farmers turned out to have a mutation—a mutation created as a result of the genetic engineering process itself (you can check out my first post on this subject here)—I was curious to learn more about the history of this genetic engineering project undertaken for humanitarian purposes.

The Golden Rice project is an attempt to use genetic engineering to alleviate vitamin A deficiency, a major cause of blindness, illness and death—mostly among young children—in developing countries where diets can consist primarily of rice and sometimes little else in the way of vegetables or other foods that contain beta-carotene, a compound that human beings can then convert into vitamin A. The project was initiated in the early 1990s and was widely publicized in 2000 when a photo of Ingo Potrykus, one of its “founding” scientists (along with Peter Beyer), appeared on the cover of Time magazine.

But it’s been 18 years since then and Golden Rice is still not available to the world’s poor who might benefit from it. Why is it taking so long to deliver this humanitarian product?

A very revealing paper by a member of the Golden Rice Humanitarian Board, Adrian Dubock, provides some answers. In it, Dubock asks “What can Golden Rice’s development history and trajectory teach us?”

SPOILER ALERT! My answer to that question—which is essentially diametrically opposed to his—is this: Check early in your GE project to identify any unintended insertional mutations in your prototype crops that were caused by the genetic engineering process, and then throw any GE “events” that have such a mutation out of your product development pipeline! (Dubock’s answer, on the other hand, might be summed up as: international regulation of GE crops, in the form of the Cartagena Protocol, impeded our progress every step of the way; more on whether regulation of GE foods is currently adequate at the end of this post.)

Are Other Developers of GE Crops Neglecting to Discard the Unintentional Mutants Created by the Genetic Engineering Process?

Golden Rice’s history also begs the questions: how many other developers of GE crops have neglected to screen their GE prototypes for insertional mutants? Are there insertional mutants among the GE crops currently on the market? (I’ve tried, unsuccessfully, to determine whether Monsanto’s NK603 GE corn was screened for this potential problem, for example.)

But I’m getting ahead of myself….

Timeline of the Development of Golden Rice

What follows is a timeline of the development of Golden Rice focused on events relevant to the problem of the potential for unintentionally creating GE mutants, a problem still faced by all developers of GE crops using the Agrobacterium-based and biolistics methods. This timeline is based on the information contained in “The present status of Golden Rice” by Adrian Dubock. (The information I mention from Dubock’s article can be found on the pages of it indicated in parentheses below; emphases are mine.)

2000: Ye et al. publish a paper describing the first “prototype” Golden Rice; the inventors of Golden Rice trade “commercial rights in the technology to Zeneca [soon to be Syngenta], in return for the companies [sic] support for the inventor’s humanitarian vision;” Zeneca is granted exclusive rights to Golden Rice technology “free of charge for humanitarian applications, but royalty bearing for commercial applications” (p.71).

The “Golden Rice Humanitarian Board is created “to advise the inventors” during its development and one of its “first agenda items was to hear the advice of a Zeneca biotechnology regulatory specialist about the molecular characteristics required of a genetically transformed GMO-crop to ensure that it would be able to be registered for use under the regulations to be derived from the very recently (2000) published, but not yet in force (2003) Cartagena Protocol on Biosafety” (p.73); the US biotech industry pays for television advertising “implying fields of golden rice were [already] growing in US fields…” and Gordon Conway, President of the Rockefeller Foundation, joins “anti-GMO activist Vandana Shiva in agreeing that ‘the public relations uses of golden rice have gone too far’” (pp.72-3).

2001: A license agreement is signed by inventor Potrykus and Dr. Ron Cantrell, director of the International Rice Research Institute (IRRI) in the Philippines, and samples of the Golden Rice prototype are hand-delivered to IRRI two days later (p.73).

2002: The Humanitarian Board asks the “network of public sector rice research institutions” to create more than 1000 additional transformation events “from which it was hoped an improved transformation event could be selected collaboratively, to be taken forward as the one lead event by all Golden Rice licensees” (p.73).

2003: New GE “events” of Golden Rice [GR1], the best of which accumulates 13 micrograms (μg) total carotenoids per gram (g) of rice, as opposed to the 1.6 µg/g in the prototype, were created and plans to conduct field and human feeding trials with some of them are made; an additional version of Golden Rice [GR2], with even higher levels of beta-carotene, looks promising in Syngenta’s labs (pp.73-4).

2004: Field trials of GR1 Golden Rice are conducted in the US; Syngenta donates GR1 and 13 GR2 “events,” at least the latter “of which were considered by [Syngenta Biotechnology, Inc.] scientists and regulatory specialists to be ready for and capable of complying with regulatory studies and standards” (p.76), to the Golden Rice Humanitarian Board and announces that it has “no commercial interest in the Golden Rice project” (p.75); the Humanitarian Board decides to concentrate efforts on 6 of the 13 GR2 individual transformation “events” donated by Syngenta (p.76).

2005: Paine et al. publish a paper describing the development of the GR2 events.

2006: IRRI requests, and Syngenta provides, molecular data on the 13 GR2 events (p.76).

2008: The field phase of a feeding trial with Chinese children is conducted; IRRI plants the first confined field trial of events of GR1 and GR2 Golden Rice in Los Banos, Philippines (p.77).

2009: A meeting of the Humanitarian Board is held in March to choose the top 2 Golden Rice events for product development; results of the feeding trial with human adults in the US are accepted for publication and presented at the meeting (p.77); agronomic data on 3 GR1 and 6 GR2 events, introgressed into 4 different indica rice varieties, were considered and Dr. S.R. Rao (Dept of Biotechnology, Government of India) asked “if there was any molecular data available to support the decision making. No such data was forthcoming (although IRRI had received it in 2006, it appeared to have been forgotten)” (p.78); nevertheless, based on the data the Board did have at hand, event GR2G was selected as the “Lead Transformation Event, with event GR2R as a back-up event if needed” (p.78); by December 1st scientists at IRRI had examined the molecular data on the GR2 events (provided by Syngenta back in 2006) and realized that the DNA inserted into GR2G, the lead event and the one used in the human bioconversion trials, contained an unexpected, unintended deletion of ~400bp; the newly found/examined molecular data also indicated that in both GR2G and GR2R the genetic engineering process had created mutations at the site in the rice genome where the foreign DNA had been inserted; but, “[d]espite the summary slide provided by IRRI, The Board had not reviewed, nor did most have the training, to ‘review all sequence data’ in any meaningful way, and it is unclear which other individuals had or the level of scrutiny afforded to it,” the decision was nevertheless made to drop the GR2G event and “bring forward” the GR2R event as the lead event (p.79).

2010: The grant to Peter Beyer from the Bill and Melinda Gates Foundation terminates; “Instead the Foundation intended to award a grant for development of Golden Rice itself to IRRI, for management of Golden Rice out of IRRI” (p.80).

2011: By October 3, GR2R seed had only been supplied to research institutes in two countries, India and the Philippines; the “inventors and the public sector Golden Rice licensees in other countries are very frustrated by this slow progress” (p.80).

2012: “Dr. Tang’s research with Chinese children, initially spoken of in 2003/2004 showed that” a bowl of cooked Golden Rice [GR2G?] “can provide ~60% of the Chinese Recommended Nutrient Intake of vitamin A for 6-8-y-old children;” “Greenpeace issued a press release condemning use of a GMO-crop, Golden Rice, with Chinese children as ‘guinea pigs of American researchers;’” [Tang et al. (2012) was later retracted (and China sacked officials in that country who were associated with the experiment) due to failure of the researchers to follow Tufts University rules regarding securing consent from research participants]; 5 multi-location field trials with GR2R are planted in the Philippines (p.80).

2013: In August one of the field trials was destroyed by anti-GMO demonstrators; data from the other 4 field trials indicated a “yield-drag” in Golden Rice GR2R compared to wild-type rice; in December, the “IRRI Network Coordinator appeared to recall the issue summarized in his December 2009 slide” indicating that the new lead event, GR2R, was an insertional mutant (pp. 80-1).

2014: IRRI posts information on its website about the poor yields with GR2R [but fails to mention the fact that it contains a mutation caused by the genetic engineering process] and that “a decision has been reached to move forward from work solely focused on GR2-R to also include other versions of Golden Rice, such as GR2-E and others” (p.81); Adrian Dubock publishes “The Present status of Golden Rice” in the Journal of Huazhong Agricultural University.

What can this history of Golden Rice teach us?

This is an astounding story. A group of humans with all the best of intentions, who apparently tried to take into account–from the very start of their work together–the regulatory requirements in the various countries for creating, transporting, and marketing a GMO food, and yet years of time and loads of effort and who knows how much money (the Gates Foundation?) were wasted on Golden Rice events that should have been culled from the “production pipeline” by 2005 (or 2006 at the latest). Sad!

Errors were made by multiple humans involved in this story. Why did Syngenta hand over mutant Golden Rice events to the Humanitarian Board in the first place? Why didn’t scientists at IRRI thoroughly examine the molecular data on those events right after they had specifically requested the information from Syngenta? Why show molecular data indicating that 2 of the 3 top Golden Rice events have their foreign DNA inserted into rice genes to a decision-making body incapable of understanding the ramifications of those mutations (that were caused by the genetic engineering process)?

We don’t know whether the insertional mutations in Golden Rice events GR2G and GR2R made the rice grains harvested from those plants unsafe for human consumption. But most mutations are deleterious, and determining whether a particular mutation would cause a problem(s) in rice that would make it unsafe for consumption would require further investigation (of each GE mutant food variety). The most expedient way to deal with insertional mutants caused by the genetic engineering process is to identify them early and eliminate them from commercial development.

Glenn et al., mostly employees of Monsanto, indicate that they now do cull GE insertional mutants in this way. But since they also indicate that they now eliminate GE events with other imprecise manifestations of the genetic engineering process from their commercial pipeline, when Monsanto certainly has not always done that, could there be any GE mutants already in our food supply? And do other developers of GE food crops follow the procedures now used by Glenn et al.?

My take on the Golden Rice story is that we need better, truly science-based regulation of GE foods, regulation that recognizes the imperfections in the technology and regulates its putative products accordingly. Regulators in every country around the world should deny “approval” of any GE food crop that contains a mutation caused by the genetic engineering process. They should do so because genetic engineering is imperfect, and humans–even those with the best of intentions–will continue to make errors, and combining this imperfect technology with error-prone humans could have negative effects on our food supply.



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Golden Rice Showcases Both the Potential Benefits and Potential Risks of Crop Genetic Engineering

It’s been nearly two years since a group of Nobel laureates published a letter supporting “Precision Agriculture (GMOs)” and, more specifically, Golden Rice, the genetic engineering project first embarked upon in the mid-1990’s to “reduce or eliminate much of the death and disease caused by a vitamin A deficiency (VAD), which has the greatest impact on the poorest people in Africa and Southeast Asia.” And although Golden Rice with its potential benefit is still not available to people suffering from VAD, a couple of significant technical and other events in the project’s development have occurred over the last couple of years that showcase some of the imprecision and potential risks inherent in the technology used to create this genetically engineered (GE) rice.

The potential benefit of Golden Rice has yet to be realized

The prospect of reducing or eliminating much of the death and disease caused by VAD is certainly an intended potential benefit of Golden Rice. But before that potential benefit might be realized, there are still many issues that remain to be addressed.

For one thing, we still don’t know whether Golden Rice will be effective in treating VAD. According to the International Rice Research Institute (IRRI), the organization developing Golden Rice “for cultivation and use in human food in certain south and southeast Asian countries,” “bioefficacy studies to determine the effect of Golden Rice consumption on various measures of vitamin A status” in humans still need to be carried out, and “appropriate regulatory authorization and institutional review board clearances” for such studies have not been obtained as of yet.

Additionally, regulatory “authorization for the unconfined environmental release of GR2E Golden Rice” and the “use of GR2E Golden Rice in food and feed, or for processing,” in the Philippines or any other country in Asia, Africa and Latin America where VAD is a serious problem, has not yet been obtained.

On the other hand, IRRI has received what it refers to as a “positive food safety evaluation” of Golden Rice GR2E from the US FDA (as well as from Food Standards Australia New Zealand and Health Canada). The short letter from FDA conveying this “positive food safety evaluation” is odd for several reasons, first just as an example of how voluntary consultation about newly developed GMOs works at that US agency. The safety-related content in FDA’s letter to IRRI is comprised primarily of “information IRRI has provided” and conclusions “it is [FDA’s] understanding” IRRI has reached. Non-administrative, safety-related FDA input is limited to the agency’s usual consultation-closing statement: “Based on the information IRRI has presented to FDA, we have no further questions concerning human or animal food derived from GR2E rice at this time. However, as you are aware, it is IRRI’s continuing responsibility to ensure that foods marketed by the firm are safe, wholesome, and in compliance with all applicable legal and regulatory requirements.” (One can see why IRRI does not refer to FDA’s position on Golden Rice as an “approval.”)

Another odd thing is that IRRI informed FDA that “GR2E rice is not currently intended for cultivation or marketing in the United States.” Which begs the question: why, since “according to IRRI, GR2E rice is intended for cultivation and use in human food in certain south and southeast Asian countries…for populations in which vitamin A deficiency is common,” did IRRI go through the “regulatory” process with the US FDA in the first place? IRRI’s answer? “…GR2E rice, or human and animal food products derived from GR2E rice, may enter the U.S. food supply via imports from countries of production.” It’s not clear whether IRRI means that the US may knowingly import Golden Rice or that its non-GMO rice imports might be contaminated with Golden Rice or both; perhaps IRRI is just trying to cover all its bets. In any case, this possibility of Golden Rice being imported into the US explains why 3 of the 6 paragraphs in FDA’s “consultation closure letter” to IRRI deal with the issue of GMO labeling.

The most striking point made in the FDA letter, however, is that the “concentration of β-carotene in GR2E rice is too low to warrant a nutrient content claim.” The whole idea of Golden Rice is to provide a necessary dietary nutrient to people at risk of, or suffering from, vitamin A deficiency…and the levels are too low to warrant a nutrient content claim with FDA?

The explanation of this paradox lies partly in the amounts of rice that Americans versus Filipinos (for example) consume. According to IRRI, to meet the FDA requirement for a nutrient claim “10 percent or more of the recommended daily intake (RDI) for vitamin A must be present as beta-carotene” in the 45 grams of rice that Americans, on average, consume daily; and the amount of beta-carotene in Golden Rice is less than that. (If the 10% threshold had been reached, I believe premarket review and/or official approval by FDA would have been required.) But the average Filipino consumes more than 6 times that much rice, and IRRI expects that if all of that was Golden Rice, “30-50% of the estimated average requirement for vitamin A” could be met in the “subgroups at highest risk of vitamin A deficiency.”

The imprecision of genetic engineering and its effects on Golden Rice 

But another reason why the concentration of beta-carotene in today’s Golden Rice is relatively low (~7.31 micrograms/gram, ~10% of the level found naturally in carrots-from safety assessment documents submitted to the government of the Philippines) is that what had been the most advanced variety of Golden Rice in IRRI’s product development pipeline, a variety with substantially higher levels of beta-carotene, GR2-R1, turned out to be a genetically engineered mutant with no market potential.

GR2-R1 had been a very promising Golden Rice “event,” with levels of beta-carotene more than twice as high those in GR2E (Paine et al. 2005). It was so promising that it was being bred into a popular rice variety called Swarna in preparation for its use by farmers in India. But the plants produced as a result of this breeding effort turned out to be stunted, pale green and have drastically low yields. To determine what was causing these problems a group of scientists in New Delhi (Bollinedi et al. 2017) carried out a molecular characterization of GR2-R1 that revealed that the foreign genes responsible for production of beta-carotene in GR2-R1 rice grains had been inserted into a rice gene called OsAux1, mutating it. The protein product encoded by this gene provides for proper function of a master growth regulator (auxin) in rice that is “involved in every aspect of plant growth and development” (Bollinedi et al. and references therein); mutating it in GR2-R1 rice caused various abnormalities in plant growth and development.

I am not at all surprised that the genetic engineering process caused this mutation. After all, we’ve known for more than 25 years that the Agrobacterium-based methods of genetic engineering cause frequent insertional mutations in recipient plants; Bollinedi et al. (2017, and references cited therein) state that 35-58% of insertions of foreign DNA sequences disrupt recipient plant genes.

What I am surprised about is that no one had (apparently) ever checked to make sure that this GE rice plant did not contain such a GE mutation prior to it being readied for farmers’ fields. Genetic engineering and associated technologies provide genetic engineers with the ability to identify such insertional mutations. Genetic engineers should be doing so early in the development of products intended for commercial release and eliminating any identified mutants from their product development pipelines. And regulatory agencies should ensure that developers of GMOs have carried out this necessary, straightforward screen of potential products.

Another source of abnormalities in GR2-R1 rice related to genetic engineering

Bollinedi et al. (2017) identified an additional problem with GR2-R1 rice, a problem that could affect other GR2 Golden Rice events as well, like the GR2E rice being readied for commercial release.

The foreign genes responsible for increasing levels of beta-carotene in all of the GR2 “events” of Golden Rice are meant to be expressed only in rice grains because expressing them in other parts of the plant could unintendedly disturb other biochemical pathways that share a common substrate, such as those involved in the biosynthesis of chlorophyll or various plant growth regulators. To accomplish this specificity, genetic engineers at Syngenta (Paine et al. 2005) spliced the “promoter” region of a rice gene called Glutelin I, which is only expressed in grain (the promoter is responsible for turning a gene on or off), to the protein-coding regions of the genes involved in beta-carotene synthesis that they wanted to insert into rice plants; then they inserted the resulting chimeric genes into rice plants via genetic engineering.

But in characterizing the abnormal GR2-R1 Golden Rice plants (produced by Syngenta as mentioned above), Bollinedi et al. found that expression of the foreign chimeric genes was not grain-specific as had been intended, the foreign genes were expressed in leaves as well. These scientists hypothesized that this “leaky” expression of the chimeric foreign genes was responsible for the pale leaves and (some of the) growth regulator-related abnormalities in GR2-R1 rice plants (because biosynthesis of green chlorophyll pigments and expression of plant growth regulators had been disrupted due to competition with the GE enzymes for beta-carotene biosynthesis). They documented dramatic alterations in the expression of four key plant growth regulator genes in support of their hypothesis.

The future of Golden Rice

In light of these problems with GR2-R1 Golden Rice that are related to the process of genetic engineering, IRRI is now concentrating on developing GR2E Golden Rice for commercial release. IRRI (in conjunction with the Philippine Rice Research Institute) submitted an application for a biosafety permit for the “direct use in food, feed, or for processing of GR2E Golden Rice,” ( to the Department of Agriculture-Bureau of Plant Industry (DA-BPI) in the Philippines in early 2017. (A link to the collection of Golden Rice data files can be found on this website:, about 2/3 of the way down the page.)

Information in the submission package appears to indicate that GR2E Golden Rice has been checked and that a mutation was not created at the site in the rice genome where the foreign genes were inserted. I’m not as convinced by the submitted data that the “leaky” endosperm promoter issue has been adequately analyzed.

I hope Golden Rice will be successful in reducing vitamin A deficiency. But we need to remember that “Precision Agriculture (GMOs)” is not as precise as some would have you believe. There is a lesson to be learned from GR2-R1 Golden Rice, and it is to be more vigilant about the less precise aspects of crop genetic engineering.

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Food Evolution Film Neglects to Mention Important Facts…Like Glyphosate is a Probable Human Carcinogen

The film Food Evolution, despite being narrated by Neil deGrasse Tyson, has been called “a slick piece of GMO propaganda” by Marion Nestle, a prominent nutrition scientist at NYU who was interviewed for it. In response to Nestle’s tweet on the subject, Michael Pollan, the journalism professor at UC Berkeley who also appears in the film, tweeted: “My experience and take much the same.” And a group of more than 45 “UC Berkeley faculty, students, alums, and community members” have also signed a statement calling this film “a piece of propaganda.”

Why? Especially since ads for the film encourage viewers to “Feast on Facts“?

Because the film neglects to mention some facts that are important for understanding the issues presented in the film, facts that are also important for getting beyond the currently polarized state of the GMO debate.

One revealing example of this cherry-picking is the film’s handling of an article published in The New York Times titled “Food Industry Enlisted Academics in G.M.O. Lobbying War, Emails Show.” Well over half of this article is devoted to emails linking three academic scientists–Kevin Folta, “chairman of the horticultural sciences department at the University of Florida,” Bruce M. Chassy, “professor emeritus at the University of Illinois,” and David R. Shaw, “vice president for research and economic development at Mississippi State University”–to Monsanto “and its industry partners.” Less than 20% of the article (by my estimate) is focused on Charles M. Benbrook, “who until recently held a post at Washington State University,” and his ties to the organic foods industry.

But only Benbrook is mentioned in Food Evolution. Viewers of the movie don’t hear anything about Folta, Chassy or Shaw.

In order to have meaningful engagement that will increase understanding of the issues involved in and affected by genetic engineering, and contribute to more informed development of future public policies on regulating the products of this powerful technology, we need all the facts. Not just the ones that zealous GMO proponents cherry-pick to tell us about.

Feasting on propaganda will only further polarize the GMO debate.

I was invited to participate in a panel discussion of the film at the University of San Francisco earlier this month. What follows is a copy of the remarks I made.


Good evening everyone.

As a molecular geneticist and a former genetic engineer, I am so very disappointed in this film…

because I believe that scientists using a new technology, especially one that contributes to our food supply, have a responsibility to be abjectly honest when explaining to the public what we know about how the technology works, how it differs from “traditional” methods, and any possible risks that might be associated with it.

And a film like this one, claiming to be science-based, with iconic public scientists like Neil degrasse Tyson and Bill Nye participating in the project, should bear that same responsibility.

Participants in a recent workshop called “Scientific Uncertainty and Professional Ethics,” sponsored by the National Science Foundation (NSF), came to a similar conclusion. They came to the conclusion that scientists should aim to “provide all the information needed to help others judge the value of their work, rather than to steer that judgment in a particular direction.”

This film fails on both counts. It doesn’t provide all the information needed to help others judge GMOs and it steers judgement in a particular direction.

The reason scientists need to be abjectly honest when explaining genetic engineering to the public is because… only by considering all the pertinent, available information—the whole truth about crop genetic engineering as we know it—can society at large make good, informed decisions about how to use and control this powerful technology.

Instead, this film leaves out important information that is crucial to an informed public debate about GMOs.

Back in the early ‘90s when I was working for a small start-up ag biotech company called Calgene, I thought we did a pretty good job of being transparent and abjectly honest, with the public and with the FDA and other regulatory agencies, about what we knew about how genetic engineering worked, how it differed from traditional breeding, and its possible risks.

We knew adding foreign genes to plants could cause mutations in the recipient plant, for example, and that sometimes the inserted DNA sequence had been changed from the DNA sequence we had intended to insert. We therefore suggested to FDA ways that we would identify and minimize such unintended effects. And frankly, I was surprised when, in May of 1992, before its scientists had thoroughly examined all the data we had sent them, FDA decided that, with only a couple of exceptions, regulation of GE food and feed crops would not be required by that agency; it put a voluntary consultation process in place instead. It remains a voluntary system to this day. [See my previous blog post for more information on the timing of FDA’s GMO policy in relation to its review of Calgene’s safety data.]

Calgene was also transparent in that it voluntarily labelled its GE tomatoes when they were first sold in grocery stores. And the public’s response to Calgene’s transparency was mostly positive. Our GE tomatoes flew off the shelves.

So I think the agricultural biotech industry got off to a pretty transparent and honest start.

But other companies have not been as transparent as Calgene was. And I believe that the lack of transparency, and the lack of abject honesty about the imperfections inherent in the technology of genetic engineering, has played a big role in the polarization of this issue over the last two decades.

Transparency gets paid a little lip service in this film, but Food Evolution still fails pretty spectacularly at being abjectly honest about genetic engineering.

For example, it leaves out important information pertaining to the safety of glyphosate, the active ingredient in Monsanto’s Roundup herbicide. It neglects to mention the fact that the arm of the World Health Organization that classifies compounds as carcinogenic—or not—the International Agency for Research on Cancer (IARC), has classified glyphosate as an animal carcinogen and a probable human carcinogen. [Since the release of Food Evolution, Monsanto sued California for using IARC’s classification to require warnings of glyphosate exposure; Monsanto lost that law suit and, on April 19, 2018, Monsanto lost its appeal of that decision as well.]

This is important information that must be taken into account in any objective discussion about the safety of glyphosate, especially since glyphosate—due to the many millions of acres of GMOs engineered to be tolerant of it that are grown and sprayed with it throughout the world—is now the most widely used herbicide on the planet.

There is no excuse for this intentional omission, and it calls into question not only the film’s honesty but its objectivity as well.

I was also disappointed with the way the film handled coverage of the safety study by Séralini and co-workers in which rats were fed either glyphosate or the GE corn called NK603 over the course of their lifetimes.

First, let me provide you with a little more information that you will need to judge the value of this study. As I’ve mentioned, unintended, off-target changes can occur in crop plants as a result of the genetic engineering process. Well, it is to check for possible negative consequences of unintended changes that GE crops/foods are fed to animals in studies like Séralini’s. We carried out similar (although not as long term) studies with our tomatoes at Calgene, and scientists at Monsanto and elsewhere also have done the same  with their GE products.

Séralini’s study was peer-reviewed and originally published in the respected international journal Food and Chemical Toxicology; it was in print for more than a year when it—very unusually—underwent a thorough review by the journal’s editor-in-chief, who reviewed not only the submitted manuscript and all the reviewers’ comments, but also the raw scientific data from Séralini’s lab. As a result of his review, he [and I quote] “unequivocally…found no evidence of fraud or intentional misrepresentation of the data” and deemed Séralini’s results “not incorrect” but “inconclusive.”

And yet, despite the fact that many peer-reviewed scientific papers present results that are not conclusive, and the fact that inconclusiveness is not a benchmark for retraction of a scientific paper, he retracted the paper anyway. The whole episode was highly unusual for a scientific community.

I say that Séralini’s original study should never have been retracted. And Professor Fred Gould, who was the chairman of the committee that put together the most recent National Academy of Sciences report on GMOs, told me [during the “on the record” Scientific Uncertainty and Professional Ethics panel discussion of GMOs and scientific uncertainty that I mentioned above] that he agreed that the paper should never have been retracted.

In the aftermath of this highly unusual Séralini retraction, I have read, in an article in Nature and elsewhere, that the inconclusiveness of the study stems from the number of control rats used, which has been deemed inadequate for attaining statistically significant conclusions. The statistician quoted in the Nature article said that, and I quote, “The study needs replicating by a truly independent laboratory using appropriate sample sizes.”

This suggested course of action is the more normal scientific response to a controversial paper…i.e., repeat the study and see if you get the same results the second time around.

Since Séralini’s results have been deemed inconclusive, we don’t fully understand what may, or may not, be unintendedly going on in rats that consume GE NK603 corn or glyphosate over the course of their lifetimes. And especially in this case, when the original study suggested—albeit inconclusively—that consuming glyphosate or GE NK603 might cause ill effects in rats, the study should definitely be repeated, and with more control rats. And frankly, I am surprised that the FDA has not required Monsanto to do so. [See this blog post for information on the unintended molecular discrepancies in NK603.]

The Séralini controversy illustrates why each GMO should be assessed on a case-by-case basis. Unfortunately, the way GMOs are currently “regulated” in the United States, some GMOs can slip through loopholes without pre-market regulation.

The Séralini controversy also illustrates why, as the World Health Organization has stated, and I quote: “it is not possible to make general statements on the safety of all GM foods.” That is because they should be assessed on a case-by-case basis to look for any that may prove problematic.

There have been several examples of problematic GMOs, a couple of which have been commercialized. And then there is NK603 [which is still on the market and] for which the jury is still out in my opinion.

I don’t believe that we should throw the genetic engineering baby out with the bath water. But we need to keep in mind that technologies can be used in many different ways: carefully or carelessly, in service to the less fortunate or for profit, or even—as Nobel laureate Richard Feynman once said—for good or for evil.

GMO foods have been on the market now for nearly 25 years. It is long past time to have an abjectly honest and truly informed public debate about how to use and control the powerful technology crop genetic engineering.

Unfortunately, this film, with its cherry-picked information, will not help us do that.

Thank you for your attention.

[I received a $300 honorarium for participating in this University of San Francisco event.]

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Update on “Extra DNA” and Other Problems with Crop Genetic Engineering

I received an email recently from a distinguished professor of plant sciences who encouraged me to update my knowledge of the “extra DNA” problem I mentioned in an article published in the January 2018 issue of Comstocks magazine. He sent me a copy of “Bringing New Plant Varieties to Market: Plant Breeding and Selection Practices Advance Beneficial Characteristics while Minimizing Unintended Changes“–a paper published in the latter half of 2017 and authored by 13 people (Glenn et al.), 10 of whom were employees of Monsanto Company–to help me do that. He indicated that Glenn et al. “describes all of the procedures, checks and tests that are done on commercialized transgenic traits to address the problem” that I had told the author of the Comstocks article has not been solved in 25 years.

Monsanto’s Current Selection Practices, According to Glenn et al.

I have to admit that I am pretty impressed with the procedures, checks and tests carried out on potential genetically engineered (GE) crop products as documented by these (primarily) Monsanto authors. For example, they indicate that molecular analyses are conducted “to ensure: (i) that only one copy of the DNA insert was in the selected events, (ii) the intactness and integrity of the DNA insert, (iii) the absence of any undesired DNA from the transformation process (e.g. the vector backbone), and (iv) that the DNA insertion had not interrupted endogenous genes.” Additional RNA and/or protein analyses “to confirm that the intended gene products were being produced” are also mentioned in the paper.

I think it should be mandatory for all developers to conduct all of these tests, and for any GE “event” (i.e. individual GE plant) being brought to market to have successfully passed them all.

The “Extra DNA” Problem is Still a Problem

But the bottom line is that the “extra DNA” problem is still a problem. Vector backbone sequences (and other unintended DNA, see below) can still get unintentionally inserted into GE crop plants. Therefore, this problem has not been solved; Monsanto still has to check to ensure “the absence of any undesired DNA from the transformation process (e.g. the vector backbone),” and that is the “extra DNA” problem I referred to in the Comstocks article. In fact, according to Glenn et al., Monsanto checks for “extra DNA” not just once, but twice during the course of bringing a new GE plant variety to market. At Calgene, Inc., back in the early 1990’s, we also checked for “extra DNA” in our tomato, cotton and brassica GMOs, and then threw out any of those GE plants that had any. Based on Glenn et al., Monsanto is doing the same thing…25 years later.

Hopefully, all other developers of GE crop plants designed for human consumption: 1) know about this problem, and 2) are doing the same.

But Monsanto’s Selection Practices Were Not Always This Strict

Take selection criterion (ii) from Glenn et al., for example: to ensure “the intactness and integrity of the DNA insert.”  In the past, Monsanto Company has commercialized multiple GE corn varieties in which the intactness and integrity of the DNA insert was not maintained during the genetic engineering process; the DNA that ended up in the GE crop after the genetic engineering process was not the same as the DNA that was intended to be inserted.

And one of the best examples of a Monsanto GE corn variety in which the integrity of the DNA intended for insertion was not maintained in the final GE corn product is NK603. NK603 is the GE corn tested by Séralini and colleagues in a long-term rat-feeding study, a study that raised concerns–and subsequently controversy–regarding possible toxic effects of NK603 (and of glyphosate-containing herbicide) on animals (see, e.g., this article on the subject in Nature). NK603 GE corn was not only commercialized as an individual GE corn product; according to a report out of Purdue University, it also has been bred into at least half a dozen other GE corn products, some of which are associated with DowAgrosciences and Pioneer Hi-Bred as well as Monsanto.

The Lack of Integrity of the DNA Insert and Intended Gene Products in NK603

The integrity of the DNA inserted into NK603 was not maintained during the genetic engineering process used to create NK603. And that lack of integrity at the DNA level resulted in a lack of integrity of the RNA expressed from the inserted gene(s), and to lack of integrity in the form of a mutation in one of the foreign proteins produced in the GE corn varieties carrying the GE locus from NK603.

According to Monsanto, in addition to a single complete copy of the DNA the company intended to insert into the recipient corn plant (which comprises two versions of genes designed to convey resistance to the herbicide glyphosate), NK603 also includes an “inversely linked 217 bp piece of DNA containing a portion of the enhancer region of the rice actin promoter at the 3’ end of the inserted DNA.” This is another type of “extra DNA” that developers of GE crops do not intend to insert into GE crops: an extra copy of a random chunk of the DNA they do mean to insert, placed randomly adjacent to the intact complete copy of the DNA they do mean to insert.

And as a result of sequencing the inserted DNA to verify its “integrity” in NK603, Monsanto identified not only the extra, inverted piece of the rice gene promoter, but also two point mutations in one of the genes conveying glyphosate resistance, “one of which results in a change of the amino acid leucine to proline at position 214 in the protein.” The other point mutation did not change the amino acid sequence of this protein. Nevertheless, the integrity of the introduced foreign protein had not been maintained.

Additionally, and perhaps of most concern in terms of understanding how the lack of integrity of the DNA insert might affect the biology of the recipient corn plant, Monsanto scientists found that expression of the inserted gene(s) in NK603 produces an RNA transcript comprised of not just information stored in the inserted DNA but also information stored in the corn DNA adjacent to the position in the corn genome into which the insert was randomly placed. That is, “mRNA transcription was detected to initiate in either one of the two promoters of the NK603 insert and…continue into the corn genomic DNA.” RNA is an intermediary molecule that conveys the information stored in DNA to the cellular machinery; some RNAs translate the information coded in DNA into a protein that, in this case, provides resistance to glyphosate; other RNAs are now known to play roles in regulating how other genes are expressed. The upshot is that an unintended gene product, a chimeric RNA molecule comprised of intended insert-DNA-associated sequences plus sequences derived from the corn DNA that just happened to be adjacent to the spot in the corn genome where the foreign DNA insert landed, is produced in NK603 GE corn and any other GE corn varieties into which NK603 has been bred using traditional breeding methods.

More Safety Studies of NK603 are Needed

 We do not know whether the lack of integrity of the DNA inserted into NK603 results in any physiological changes in GE corn plants comprised of this GE corn event.

But we do know that if NK603 had been put through the procedures, checks and tests described in Glenn et al., it would have failed them.

In the meantime, we also know that Séralini and colleagues documented problems in rats fed NK603 over their lifetimes in a study that passed peer-review and was published in a reputable international journal (Food and Chemical Toxicology), but was retracted–more than a year after it had been in print–by the journal’s editor-in-chief after he deemed it “inconclusive.” We also now know that Monsanto played a behind-the-scenes role in the public attack on that study that resulted in its retraction.

What we need now is for that study to be replicated “by a truly independent laboratory using appropriate sample sizes” (David Spiegelhalter, a statistician at the University of Cambridge, UK). We need an update on NK603.

I, for one, would like to know–conclusively–the safety status of NK603 GE corn.

I would hope that the United States Food and Drug Administration, and its counterparts in other parts of the world, would want to know as well.


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Monsanto, Henry Miller, and the FDA

I have been reading with interest various articles reporting on the trove of internal documents obtained from Monsanto during the discovery phase of a federal multidistrict litigation against that company that is currently pending in the United States. (The documents, and a list of articles from all over the world that have been written about them, can also be found on the website of the NGO US Right to Know.)

Attorneys with Baum, Hedlund, Aristel & Goldman, the firm representing hundreds of plaintiffs across the US in the case, indicate that these so-called “Monsanto Papers” “tell an alarming story of corporate malfeasance. They reveal that Monsanto has been manipulating the science…ghost-writing scientific literature…bullying scientists that publish anything negative…and colluding with regulators to ensure ‘positive’ assessments.”

I was especially intrigued to learn that Henry Miller, who was described in The New York Times as “an academic and a vocal proponent of genetically modified crops,” is implicated in the ghost-writing scandal, albeit in regard to a non-academic journal. As reported in The Times, Dr. Miller “asked Monsanto to draft an article for him that largely mirrored one that appeared under his name on Forbes’s website in 2015.” Forbes has since taken the article in question down from its website and ended its relationship with Dr. Miller.

What was not mentioned in the article in The Times, and the reason for my intrigue, is the fact that Dr. Miller was the founding director of FDA’s Office of Biotechnology from 1989 to 1994. During that timespan, Calgene Inc., was seeking approval from FDA to commercialize what turned out to be the first genetically engineered (GE) whole food to enter the marketplace, the Flavr Savr™ tomato. Back then I was part of a team of scientists at Calgene conducting safety studies, explaining to FDA scientists how the genetic engineering process we were using worked, and participating in a dialogue with those FDA scientists about what possible risks might be associated with crop genetic engineering technology.

I have always felt that the timing of the release of FDA’s policy for dealing with GE food and feed products (not to mention the policy itself) made no sense. And now I am wondering how long the relationship between Dr. Miller and Monsanto, which appears to have included ghost-writing in support of that company, has been going on.

Initial safety data on the first GE whole food had been submitted to FDA, but not yet evaluated by the agency, when the May 1992 FDA policy was established

We at Calgene had submitted a large package of data that we hoped demonstrated the safety of our GE tomato to FDA in August of 1991. We had submitted a similarly large package of safety data related to use of a gene conferring resistance to the antibiotic kanamycin, a gene Calgene and most other biotech companies insert(ed) into crops during the genetic engineering process, some 10 months earlier.

But before FDA had responded to these data packages, first by asking questions about their scientific contents and then by asking for more data to support our safety claims—which the agency ended up doing on at least five occasions, FDA came out with its policy for how to “regulate” GE food and feed products in May of 1992. That FDA policy was simple. With only a couple of exceptions, it called for developers of GE food/feed products to voluntarily consult with the agency about them.

The timing of the May 1992 policy just didn’t make sense to me. Why hadn’t the agency waited until it had thoroughly evaluated the safety of (at least) the first GE food product, Calgene’s Flavr Savr™ tomato, before it came out with its policy for “regulating” all GE food/feed products? And, because FDA had not completed evaluation of Calgene’s—or any other developer’s—safety-related data prior to publishing its policy for “regulating” GE foods, how could that policy be based on science?

Thorough evaluation of Calgene’s safety data revealed scientific “surprises” that I feel are relevant to FDA regulation of GE foods

As it turned out, FDA scientists, and we Calgene scientists as well, continued to discover and deal with scientific issues related to the genetic engineering process in general, and the Flavr Savr™ tomato in particular, for some 18 months after the May 1992 FDA policy was published.

For example, FDA contacted Calgene multiple times between December 1992 and September 1993 about concerns they had with one scientific experiment in which minor gastric lesions developed in the stomachs of 7/20 female rats fed one particular variety of Flavr Savr™ tomato. In response, Calgene conducted multiple, various additional studies on that GE tomato variety until FDA was satisfied as to its safety.

And some six months after the May 1992 FDA policy was published, FDA scientists also asked Calgene to carry out experiments to demonstrate that only the foreign DNA we intended to insert into our tomatoes was, in fact, inserted into them. I, for one, was flabbergasted to find out that in about 20% of our GE tomatoes (and other GE crop plants transformed using the Agrobacterium method), much more foreign DNA—and DNA that was not well characterized at that—had been inserted than we had intended. To my knowledge, this “extra DNA” problem still has not been solved and so crop genetic engineers just have to look for extra DNA in each GE plant and throw out those that contain any.

What might FDA’s policy for regulating GE foods/feeds have looked like had the agency waited until after it had concluded evaluation of Calgene’s safety data to set its policy?

If FDA had waited until after it had reviewed all of Calgene’s data, and until after the scientific issues that surfaced during that review had been resolved to its satisfaction—i.e. until a point at which it could base its policy on some actual science—its policy for regulating GE crops might have been very different. FDA might have required that developers check their GE crops for DNA that was not intended to be inserted into them, for example, and/or required animal-feeding studies of new GE crops as is required in the European Union.

So why didn’t FDA wait until it had evaluated all of (at least) Calgene’s data, and then establish its policy based on that relevant science?

Could FDA’s failure to wait until after it had completed evaluation of the relevant data it had in hand before publishing its policy for “regulating” GE foods have had anything to do with a relationship between Henry Miller, Director of FDA’s Office of Biotechnology at that time, and Monsanto?

Back when Henry Miller was serving as the first director of FDA’s Office of Biotechnology (1989-1994), we at Calgene had heard rumors that Monsanto was not happy that Calgene, a little start-up company, might set regulatory precedence with FDA by being first to commercialize a GE whole food. And we knew that Monsanto employees were also in dialogue with FDA during the years leading up to publication of the FDA policy in May of 1992.

I have read many of Miller’s writings since then and often wondered how much he might have been influenced by Monsanto as the 1992 policy was being set. Especially since, as Monsanto’s Vice President for global strategy, Scott Partridge, told The Nation recently, “the [regulatory] process requires a tremendous amount of contact and interaction with the government.”

Now that it has come to light that Monsanto has apparently ghost-writen for Miller about RoundUp/glyphosate, I am even more curious about what kind of influence that company might have had over Miller back when the FDA policy was being formed.

Monsanto’s influence on EPA

After all, the “Monsanto Papers” suggest that Jess Rowland, a (now former) deputy director of the EPA’s pesticide division, had the kind of relationship with Monsanto that caused Congressman Ted Lieu to ask the Justice Department to investigate the possibility of collusion between Monsanto and EPA employees reviewing glyphosate, the herbicide-active ingredient in RoundUp. (And, as reported in The Nation, the EPA’s Office of the Inspector General has claimed to be looking into that.)

So I wonder: how might Monsanto have influenced Henry Miller, back in the early 1990s when he was director of FDA’s Office of Biotechnology (1989-1994), on the subject of how genetically engineered foods should be regulated by FDA?

Posted in Biotechnology | Tagged , , , , , , , , , , , , , | 5 Comments

Transparent Information about the GMO Ingredient(s) in the “Impossible Burger”

Have you heard about this new non-meat burger that—due to an ingredient produced in a genetically engineered (GE) yeast—has a taste and “blood” like what you would expect from the real thing?

Or, since they are already commercially available for human consumption in 56 restaurants across seven American states, perhaps you’ve already eaten one?

Well, whether you are eating them daily or you’ve never heard of them, you may want to get to know them better because, as quoted in The New York Times [explanatory insertions mine], “F.D.A. believes the arguments presented [by the developers of Impossible Burger], individually and collectively, do not establish the safety of [the GE] soy leghemoglobin [it contains] for consumption, nor do they point to a general recognition of safety.” It was also reported in that article that the “agency has expressed concern that [soy leghemoglobin] has never been consumed by humans and may be an allergen.”

Yes, you read that correctly. The United States Food and Drug Administration (F.D.A.), the U.S. agency “responsible for ensuring the safety of most of the U.S. food supply,” has expressed qualms about the safety of a “key” ingredient in this new “plant-based” burger…and yet you could have one for lunch today at a Hopdoddy or Umami Burger near you.

How is that possible? you may be asking yourself. (Or, “Isn’t that impossible?” might be more appropriate in this case.)

Stephanie Strom’s NYT article is a good place to start for information on this Impossible Burger specifically, as well as for the basics on how food additives and ingredients are—or are not—regulated in the United States more generally.

Turns out, Impossible Burger and other high-tech food developers, have been interpreting a 1958 amendment to the 1938 Food, Drug and Cosmetic Act (FDCA) to mean that they can “self-affirm” a food additive or ingredient as “generally recognized as safe” (GRAS) and then go ahead and market such self-affirmed foods without consulting with, or even notifying, the F.D.A.

But advocacy groups like the Center for Food Safety and the Environmental Defense Fund do not interpret the 1958 amendment that way. EDF’s Tom Neltner was quoted in the NYT article as saying that “The [1958] exemption was meant to cover ingredients that had long been used in the food supply…. It wasn’t meant to allow companies to simply bypass the F.D.A.” And it was not, I would explicitly add, meant to exempt a protein that “has never been consumed by humans and may be an allergen.”

The U.S. Government Accountability Office (GAO) also has a problem with this state of affairs. It released a report in February 2010 titled “FDA Should Strengthen Its Oversight of Food Ingredients Determined to Be Generally Recognized as Safe (GRAS).” But, apparently, F.D.A. has yet to do so.

As I mentioned in my last post, F.D.A. and other U.S. government agencies are currently re-evaluating how foods and food ingredients developed using the techniques of modern biotechnology should be regulated. Hopefully, this major “GRAS loophole” will be eliminated as part of overhauling that regulatory process. (But I, for one, am not holding my breath.)

In the meantime–and especially since Rachel Konrad, a spokesperson for Impossible Burger, informed the NYT that “we believe the public wants and deserves transparency and access to any information they need to decide for themselves whether any food they might eat is safe and wholesome”–below you will find additional information about the GE soy leghemoglobin (etc.) in Impossible Burgers:

  • Konrad stated that “A key ingredient of the Impossible Burger—heme—is an ancient molecule found in every living organism.” But the GE protein that releases that heme in Impossible Burgers when they are cooked–soybean leghemoglobin produced in a GE yeast strain–is a protein naturally found in soybean roots that, as mentioned by the F.D.A. (and noted in the NYT article cited above), “has never been consumed by humans.” It therefore only seems sensible that F.D.A. should not allow a protein that has never been consumed by humans to be self-affirmed by its developer as GRAS.
  • In a document acquired from FDA through the Freedom of Information Act (by the ETC Group, a Canadian environmental organization, and shared with the NYT), Impossible Burger argued that soybean leghemoglobin “is substantially similar [my emphasis] to proteins consumed daily by the global population, in the form of meat and other vegetables” and that “Impossible Foods does not believe that consumption of this protein presents any issues of safety to the consumer.” But this is not a scientifically sound argument, and F.D.A. noted in the FOIA-acquired document that discussion of proteins other than soy lehemoglobin “is not relevant” to safety assessment of the Impossible Burger; and that is because for proteins, even “a relatively small difference in sequence or PTMs [post-translational modifications] can result in a large difference in function, which can be important in predicting protein functions, regulation of protein functions, and in the evolution of new functions” (Jeffery 2016). This “substantially similar” argument comprises a whole new level (a new order of magnitude?) of the “substantial equivalence” argument that has been used by the developers of GE foods up until this point in time. It is an argument that has no basis in protein science as related to safety evaluations and, in my opinion, rather than GRAS, Impossible Burger’s leghemoglobin could be considered a food additive and regulated as such at F.D.A.
  • Additionally, Impossible Burger told FDA that the soy leghemoglobin will be extracted from GE yeast “cells and purified away from other cellular proteins, with a resultant purity of approximately 73% leghemoglobin. The non-target proteins which may co-purify are expected to be safe for consumption based on history of safe consumption of the whole yeast in animals.” But among the many non-target proteins that “may” co-purify with the GE leghemoglobin, Impossible Burger lists “Hypothetical proteins” and “Unnamed protein products.” Impossible Burger may expect those hypothetical proteins and unnamed protein products to be safe, but that doesn’t mean that consumers like me have to.


Posted in Biotechnology | Tagged , , , , , , , , , , , | 5 Comments

Informing USDA’s and FDA’s Thinking About Crops/Foods Derived From Plant Varieties Produced Using Genome Editing Techniques Like CRISPR-Cas9

Both the U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) and the U.S. Food and Drug Administration (FDA) have asked the public for comments on how these agencies might deal with crops and foods derived from new plant varieties produced using new genome editing techniques like CRISPR-Cas9. Public comments are due to both agencies by June 19, 2017 and can be submitted to USDA APHIS here and to FDA here.

I submitted the following comments to these agencies in response to the notices published by APHIS and FDA in the Federal Register last January.


June 16, 2017: Comment to APHIS Re: Proposed revisions to the regulations at 7 CFR part 340

My name is Belinda Martineau, I am trained as a plant molecular geneticist and I was a part of the team of scientists at Calgene, Inc. that carried out safety studies of the Flavr SavrTM tomato in Calgene’s successful effort to gain U.S. regulatory approval for commercializing that genetically engineered (GE) crop product. I thank USDA APHIS for providing this opportunity for the public to comment on the agency’s proposed revisions to the regulations applying to GE crops and for being transparent throughout this process.

It is long past time to make the piecemeal and loop-hole-filled “coordinated” framework for regulating GE crops and other organisms more science-based and more coordinated among the U.S. regulatory agencies involved. Rather than “concern in the 1980s that if an organism was modified using genetic material taken from a plant pest, or a plant pest was used as a vector or vector agent to carry genetic material into an organism, the resulting GE organism could also be a plant pest,” APHIS has used its authority over plant pests to regulate GE organisms over the last three decades because it appeared to be its only means for doing so. The best option for regulating GE crops, back then and now, would be to pass specific legislation for regulating GE crops, rather than to continue forcing a round technology into a square and scattered regulatory hole—an option that would have to be taken by the legislative branch of our government. APHIS mentioned several putative options related to regulating GE crops that would require new legislation in the Federal Register (Vol. 82, No. 12); a complete overhaul of GE crop regulations via legislation should also be considered.

In the meantime, APHIS now considers it “both appropriate and necessary to begin to evaluate GE plants for noxious weed risk.” And, based on the definition of a noxious weed provided in the 2000 Plant Protection Act (PPA), i.e. ‘‘Any plant or plant product that can directly or indirectly injure or cause damage to crops (including nursery stock or plant products), livestock, poultry, or other interests of agriculture, irrigation, navigation, the natural resources of the United States, the public health, or the environment,’’ this aspect of APHIS authority could be used to regulate most GE crops. (NB: no mention of “invasiveness” is made in the PPA definition of a noxious weed.) For example, APHIS now knows that deregulating glyphosate-resistant GE plants has indirectly caused substantial damage to various crops and other interests of agriculture in tens of U.S. states through the development of glyphosate-resistant superweeds. And based on the scientifically based concept of selection pressure, there is every reason to believe that deregulation and consequent wide cultivation of any other herbicide-resistant GE crops will similarly result in development of superweeds resistant to those herbicides and thus result, indirectly, in similar damage to crops and other interests of agriculture. Thus, based on the 2000 PPA, any herbicide-resistant GE crops should be regulated by APHIS; i.e. the regulatory status of herbicide-resistant GE plants should definitely not be “not regulated” (as they are currently on APHIS’s example list).

Additionally, glyphosate-resistant plants could indirectly injure livestock and/or public health since glyphosate is an animal carcinogen and a probable human carcinogen. Therefore, glyphosate-resistant plants should be categorized as noxious weed risks and should be regulated.

In a truly “coordinated” framework for regulating GE crops, APHIS should take the damaging indirect effects of herbicide-resistant GE plants into account when evaluating GE crops for noxious weed risk as per the 2000 PPA definition, and not simply categorize damage associated with application of an herbicide as a concern for the EPA instead. And the “asynchronous timing of the deregulation of herbicide-resistant plants and the associated herbicide registration” must simply end; if APHIS and EPA can’t coordinate such timing for GE crops and the herbicides or other chemicals designed to be specifically applied to them, the “coordinated” framework is broken.

Based on the 2000 PPA definition it also appears that most, if not all, GE crops could be classified as noxious weed risks in terms of their ability to indirectly cause damage to “other interests of agriculture,” such as the economic interests of U.S. farmers who grow non-GMO crops. When the crops of these farmers become intermixed with GE crops, via cross-pollination or post-harvest, economic losses in sales within and outside of the U.S. have been, and can be again in the future, substantial. USDA has expressed concern over this intermixing problem in the past. And the as yet unconfirmed possibility that a GE corn crop developed for biofuel may have been intermixed with corn used for masa and tamale production last winter ( ) serves as an example of how this intermixing problem could cause economic losses to “other interests of agriculture”…or worse. Therefore APHIS should utilize the PPA of 2000 to regulate GE plants/crops to protect against damage to important “other interests of agriculture” in the U.S.

I agree with APHIS’s definitions of genetic engineering and GE organism, but not with its exclusion “from its definition of GE organism, certain organisms that are created using techniques that fall within the scope of genetic engineering….” It is inappropriate and not scientifically sound to minimize concern over the off-target effects which occur as a result of the use of the new genome-editing types of genetic engineering techniques, as well as those that can occur when using the older Agrobacterium-based and biolistics techniques. APHIS states that chemical and radiation-based mutagenesis can create “thousands of mutations in a single organism, and most of the plant breeders’ subsequent efforts involve eliminating unwanted mutations by repeated crosses and selection….” But an off-target activity rate of ≥50% has been reported in the scientific literature for the CRISPR/Cas9 genome editing technique, for example ( ), and thousands of off-target changes were recently reported in a CRISPR–Cas9-edited mouse ( ), indicating that “single base pair substitutions, as well as deletions of differing sizes” are not as “precisely administered” using genetic engineering as implied by APHIS. And the fact that these off-target changes may comprise “small genetic differences” which may be “not phenotypically observable” does not mean that they are not of concern; most mutations are deleterious, and crops can produce toxic compounds that are not phenotypically observable. As long as there are such high rates of off-target effects associated with genetic engineering, all GE organisms should be evaluated by APHIS for plant pest and noxious weed risk, no exceptions.

The language in the proposed preliminary/provisional Regulatory Status Evaluation Requirements posted on the USDA website ( ), appears to be appropriate for evaluations of the regulatory status of all new crops produced using any GE technology—including genome editing and synthetic biology. But based on the history of GE crops, which includes indirect damage to U.S. crops via superweeds and economic losses due to contamination of non-GMO crops with GE crops, and the fact that off-target effects can occur during the genetic engineering process, it is appropriate for APHIS to require all new GE products to undergo its evaluation process, no exceptions; all developers of GE crops should be required to request a regulatory status evaluation for each new GE product that is developed, on a case-by-case basis prior to each product’s commercialization, and to fulfill the (putative) Regulatory Status Evaluation Requirements described on the USDA website.

I agree with the requirement in step 2. of the proposed preliminary/provisional Regulatory Status Evaluation Requirements, requiring that developers provide “The genotype of the modified organism, including a detailed description of the differences in genotype between the organism subject to the inquiry and the recipient organism.” However, the more specific requirements listed under step 2. fail to explicitly mention a requirement to characterize modified organisms for off-target effects; just as USDA APHIS is proposing that developers submit alignments of modified sequences with the unmodified sequences for intentionally inserted or edited sequences, a truly “detailed description of the differences in genotype between the organism subject to the inquiry and the recipient organism” would require alignments of the entire genomes of the two in order to identify possible off-target effects. The most recent National Academy of Sciences report on GE organisms recommended that techniques used in the various “omics” fields of biology should be employed in characterizing GE organisms; APHIS should require the use of whole-genome sequencing (WGS) to identify all off-target mutations in GE organisms (as was used in the genome-edited mouse study mentioned above: ).


June 16, 2017: Comments to FDA Re: Docket No. FDA-2016-N-4389, Genome Editing in New Plant Varieties Used for Foods; Request for Comments

My name is Belinda Martineau, I am trained as a plant molecular geneticist and I was a part of the team of scientists at Calgene, Inc. that carried out safety studies of the Flavr SavrTM tomato in Calgene’s successful effort to gain U.S. regulatory approval for commercializing that genetically engineered (GE) crop product, which included FDA’s approval of the kanamycin-resistance-conferring protein in those tomatoes as a food additive. I thank FDA for providing this opportunity for the public to help inform the agency’s “thinking about foods derived from new plant varieties produced using genome editing techniques.”

Comments on Question 1.

The greater the ability of a developer of a new plant variety to specifically target an intended change to a specific, hopefully “safe” locus in a crop genome; and the fewer off-target, unintended disruptions (such as insertional mutations, additions of minimally characterized vector backbone sequences, and changes in the relative positions of protein-coding genes, microRNA genes and other elements of genome architecture like enhancers and silencers) that are made elsewhere in the crop genome; and the more collective knowledge that is available about the technique and that is known to and utilized by the developer; and the more fail-safe systems the technique has, the safer the resulting new plant variety will be. A comparison of genome editing and other means for developing new plant varieties in terms of these safety-related characteristics is shown in the table (below).

Unfortunately, scientific knowledge of and experience with plant varieties developed with in vitro recombinant DNA technologies and commercialized over the last 23 years have not provided much in the way of helpful information to be applied to safety assessment of new plant varieties produced using genome editing. If FDA had required developers to conduct long-term animal feeding studies of these new plant varieties, for example, we would now have a better idea of how often unintended, off-target effects might have negative implications for food safety. In fact, even when a long-term animal feeding study did suggest that Monsanto’s NK603 GE corn variety might have negative unintended effects (even if the study’s conclusions were deemed “inconclusive” after thorough examination of all the raw data associated with that study by the editor-in-chief of the peer-reviewed journal it was originally published in: ), FDA did not require that developer to provide additional data and/or information to support the safety of their product; I think FDA should have done so. And the flaws associated with the older non-targeted genetic engineering techniques remain; I know of a company that did not know until recently that backbone vector sequences can be inadvertently inserted into new plant varieties transformed using the Agrobacterium-based method. If FDA had required developers to check to ensure that they had not inadvertently inserted their genes of interest into an endogenous plant gene or vector backbone sequences into the recipient plant genome, and if FDA had required developers to conduct long-term animal feeding studies, we would now know a lot more about how to deal with off-target effects.

Comments on Question 2 and 3.

The fact that developers can select a specific gene in a crop to “edit” as opposed to the relatively random insertion of genes–often (27-63% of the time) into another gene thereby mutating that gene–that occurs when using the older genetic engineering methods is a major advantage of the new genome editing technologies. (Although these technologies will also be used to insert foreign genes into plant genomes, and selection of a “safe” site for intended insertion will be an issue in those cases.) However, an off-target activity rate of ≥50% has been reported in the scientific literature for the CRISPR/Cas9 genome editing technique, for example ( ), and thousands of off-target changes were recently reported in a CRISPR–Cas9-edited mouse ( ). A professor of plant biology at UC Davis stated at a public lecture recently that of the many, many peer-reviewed scientific papers he had read in which the CRISPR method had been used in the reported study, every single one of them also reported off-target effects. These high rates of off-target effects, and the mutations they may result in, make genome-edited plant varieties more likely than traditional-bred plants to present food safety risks. Most mutations are deleterious. Until we know more about such off-target effects and how they might be reduced/eliminated, all products/foods created using these new technologies should be regulated in the U.S., no exceptions. The high rates of off-target events, combined with the newness and consequent lack of experience in using these new technologies to produce foods for human consumption, provide support for FDA taking this cautious and prudent stance with regard to genome-edited foods at this time.

Comments on Question 4.

The step FDA should take to ensure that small firms—as well as large firms and all aspiring developers of genome-edited food or feed organisms—engage with FDA about the safety of such GE foods or feeds is to make engagement with the agency mandatory prior to commercialization of such products. FDA should also establish a mandatory safety evaluation process for these products. The most recent National Academy of Sciences report on GE organisms recommended that techniques used in the various “omics” fields of biology should be employed in characterizing GE organisms; therefore, FDA should, for example, require the use of whole-genome sequencing (WGS) to identify all off-target changes/mutations in all GE organisms (as was used in the genome-edited mouse study mentioned above: ). Advances in molecular technology should be used not just to create new GE foods or feeds, but to ensure that they are safe for long-term consumption as well.

Summary of differences and similarities of various means for developing new plant varieties:

  Ability to target intended change to particular locus in genome Can create off-target, unintended changes in recipient genome (e.g. mutations) Can cause changes in relative positions of genes* Human experience with technique (years) Presence of evolved bio-chemical checkpoint pathways to help ensure proper function  
Hybridization Yes (in terms of synteny) Yes Not usually ~12,000 (domestication)

~120 (Mendelian genetics)


Chemical mutagenesis No Yes Not usually ~70 No  
Radiation-induced mutagenesis No Yes Yes ~90 No  
Agrobacterium-based** (insertional mutagenesis) No Yes Yes ~30 No  
Biolistics (insertional mutagenesis) No Yes Yes ~30 No  
Genome editing (in/dels, gene editing) Yes Yes Yes or No, depending on use ~4 No

* Changes in the position of a gene within a genome, e.g. abnormally juxtaposing a gene with heterochromatin ( ), can silence or otherwise alter normal gene expression patterns.

** Approximately 20% of the time, this method also leads to insertion of vector “backbone” sequences ( ) which, depending on the vector used, may be associated with additional safety risks.



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