Fred Gould, the chairman of the committee that produced the most recent National Academies report on GMOs, and I were invited to speak at the third and final NSF-funded workshop on the topic of “Scientific Uncertainty and Professional Ethics: Getting from Strong Public Science to Sound Public Policy,” which I mentioned in my last post: Pew Research Center Finds “Americans have Limited Trust in Scientists Connected with Genetically Modified Foods.” The workshop was held the Monday following the release of that Pew Research Center report. Dan Charles, a journalist who published a piece on the Pew report for NPR and authored a book on GMOs titled Lords of the Harvest: Biotech, Big Money and the Future of Food (Perseus Publishing, 2001), moderated our session of the workshop.

Workshop participants, comprised of scientists, journalists and environmental attorneys, were using crop genetic engineering as a case study of how scientific uncertainty is communicated, to the public and otherwise. The entire workshop was “on the record.”

In his presentation Dr. Gould reiterated a point made in his NAS report [emphasis mine]:

“With regard to the issue of uncertainty, it is useful to note that many of the favorable institutional statements about safety of foods from GE crops [such as those mentioned in Box 5-1 of the report] contain caveats, for example: ‘no overt consequences,’ ‘no effects on human health have been shown,’ ‘are not per se more risky,’ and ‘are not likely to present risks for human health.'[see * below] Scientific research can answer many questions, but absolute safety of eating specific foods and the safety of other human activities is uncertain.”

Dr. Gould also mentioned that the media often fail to mention these caveats.

(I would add that many crop genetic engineers and other vocal GMO proponents often fail to mention them as well. See, for example, The Absurdity of Claiming that “All GMOs are Safe.”)

I then briefly explained some sources of the uncertainty associated with crop genetic engineering that necessitate—for the sake of abject truthfulness—mention of such caveats.

I described how introducing DNA into an organism via genetic engineering involves biological processes that are very different from traditional cross-breeding (see my post on this topic here), and that plant scientists know that mutation of recipient plant genes and/or insertion of large chunks of vector DNA not meant to be inserted into genetically engineered (GE) crops (when using the Agrobacterium-based method) can occur at what I consider to be relatively high rates (20% to greater than 60%). (For more details about these uncertainties that we know something about please see Crop Genetic Engineering, Warts and All.)

I also mentioned our current lack of knowledge (i.e. ignorance) about the genomes of plants (and other organisms), how we don’t know the function of most of the DNA that comprises them beyond the small amount (~2-3%) that codes for proteins but that it has become clear that at least some of the oft-called “junk” DNA is actually important for proper gene expression and function. And because scientists have no control over where in a crop plant’s genome their foreign genes will be inserted (when using the genetic engineering techniques used over the last 30 years anyway), insertions could disrupt protein-coding genes (causing mutations) or non-coding regions of DNA with unknown but possibly important functions.

I then explained that the reason animal-feeding studies are carried out with GE crops is to look for possible unintended consequences–AKA pleiotropic effects–that might have occurred as a result of such scientific uncertainties. I went on to say that if such studies suggest possible negative consequences—as was the case with the peer-reviewed 2012 study of NK603 corn conducted by Séralini and colleagues, for example—the proper scientific response is to repeat the study; instead, that 2012 study was retracted for being “inconclusive” more than a year after it had been in print. (For more information on various safety-related issues with GE crops, and the controversy over the Séralini publication, see A Dearth of Life-Long Animal Studies of GE Foods and Science-based Regulation of GE Crops Requires More Long-Term Rat Feeding Studies with NK603 Corn.)

I also mentioned that, in my opinion, plant scientists have not done a good job at being abjectly honest and transparent about the scientific uncertainties associated with genetic engineering; instead many have made general statements about its precise aspects, about all GE food/crops being safe, about genetic engineering being just an extension of traditional breeding…statements that gloss over the scientific uncertainties that I believe it is the responsibility of scientists to provide to society so that society, as a whole, can make good decisions, based on all the available information, about how to use and control a technology.

I additionally mentioned that the physicist Richard Feynman expressed this same philosophy of science and technology.

After some Q&A, Dr. Gould and other workshop participants agreed that the NK603 paper by Séralini and colleagues should never have been retracted.

Dr. Gould also agreed that the technology of crop genetic engineering had been “over sold.” He additionally said, and his report indicates as well, that use of new scientific techniques, including the various “omics” technologies, should help in evaluating the safety of GE crop products.

But in response to the final question asked during our workshop session, “Do you believe that all GE crop products currently on the market are safe?” Dr. Gould answered “yes” even after I reminded him specifically about NK603.

I said that I feel the jury is still out on NK603 GE corn.

Just a couple of weeks later, more evidence (along with some controversy) came to light. “An integrated multi-omics analysis of the NK603 Roundup-tolerant GM maize reveals metabolism disturbances caused by the transformation process” was published in Scientific Reports.

I’d say the jury remains out on NK603 GE corn.

* More caveats, as well as means of dealing with them, are mentioned in this last example when the entire quote from the World Health Organization is referenced (rather than the partial quote cited in the NAS report):

“Different GM organisms include different genes inserted in different ways. This means that individual GM foods and their safety should be assessed on a case-by-case basis and that it is not possible to make general statements on the safety of all GM foods.

GM foods currently available on the international market have passed safety assessments and are not likely to present risks for human health. In addition, no effects on human health have been shown as a result of the consumption of such foods by the general population in the countries where they have been approved. Continuous application of safety assessments based on the Codex Alimentarius principles and, where appropriate, adequate post market monitoring, should form the basis for ensuring the safety of GM foods.”