Several weeks ago, the USDA announced it had confirmed the presence of Roundup-Ready wheat in an Oregon field. Roundup-Ready wheat underwent field trials in the late 90’s and early 00’s, but trials were suspended before final approval was granted. The wheat is a match to the exact strain tested by Monsanto. Now it appears somebody may have planted evidence (sorry, couldn’t resist at least one bad pun):
“None of standard farming practices are consistent with, or can explain, a smattering in only one percent of a field or in patches or clumps,” he said. “In our view the finding is suspicious.”
The strain of wheat has never been shown to be harmful, and it carries the same genetic construct as several Roundup-Ready crops that have been approved. But the wheat has not completed the approval process, so the finding caused considerable concern.
A few days ago Kevin Folta, a colleague whose main research focuses on strawberry genetics and crop improvement, tweeted a link to an interview he did with HuffPost Science. The video sums up a lot of the same ideas I try to communicate in my classes about genetically-modified foods, both their risks and their benefits. The post on HuffPo Science has received almost 2000 comments as of this writing, so it clearly struck a nerve.
One of the points he makes is that humans have been doing genetic modification for tens of thousands of years. All of our crop plants are the result of mutation, selection, natural hybridization, and in some cases, deliberate hybridization. There is no such thing as ‘natural corn’ — it is the product of human civilization and could not survive without us. And when genetic modification happens naturally or through traditional plant breeding, whole genomes are scrambled. Modern genetic engineering allows targeted access to a single gene at a time, either by inserting a new, well-studied gene into a plant, or regulating the expression of an existing gene. But for some reason, the backlash against the modern, targeted approach is far beyond that of other techniques.
Sometimes the backlash is motivated by a disdain for the large companies that control so much of our food supply (and our politicians). But there is also a genuine fear that scientists are messing around with things they don’t understand and it will kill us all, or at least seriously mess up our lives and environments. I am all in favor of testing new crops for human and environmental safety. I believe crop biotechnology deserves neither a free pass nor impossible regulations. To hold transgenic crops to a standard that they be proven to do no harm to an ecosystem (an effectively impossible claim to uphold) when no other crop has ever been held to such a standard is hypocritical.
Yesterday saw a flurry of reports about a new article in Science on tomato flavor, or the lack thereof. Here are a few:
While it’s great to see such widespread coverage of a plant science discovery, as I read through each report I couldn’t help but notice the disconnect between the bold titles and the substance of each article.
Here is the science: the researchers found the molecular identity of a historical mutation in fruit development that plant breeders have selected for that makes the fruits more uniform in color and lighter green. The gene encodes a transcription factor that controls chloroplast development. When mutated, as in almost all cultivated tomatoes, it leads to fruits with fewer chloroplasts, which explains the lighter, more uniform coloration. It also leads to lower carbohydrate and pigment concentrations, which the researchers suggest could impact flavor.
The problem with the bold article titles is, the flavor of a tomato is much, much more complex than its sugar content. Tomatoes contain over 400 volatile compounds, each of which interacts with the others and nonvolatile compounds to produce the overall flavor profile. Understanding how each of those hundreds of molecules is formed and processed in the fruit throughout ripening is likely to yield better tasting tomatoes, and maybe having more total carbohydrates will be a part of that process. But the original article didn’t even begin to explore flavor, so why is that the take-home message of all the news pieces?
To me, the Science paper is extremely interesting, but not for the reasons highlighted in these articles. This is a case of classical breeding carrying out selection on a trait that seemed to improve the crop, at least from the standpoint of the grower, making it more consistent and easier to market. But now that we know what (in the molecular sense) they were selecting, we can see it was probably a poor tradeoff. This is yet another in a long line of links between classical breeding choices and molecular genetics, and this represents an excellent way to educate the public that all of our food is genetically modified! It all has DNA! Genes, even! I continue to be fascinated as we uncover the ancient — and recent — mutations that produced the foods we know, and I think it provides a great chance to inform and begin a dialog over the nature of farming, breeding, and genetics.