Life goes on as gene-edited foods begin to hit the market. Japanese consumers have recently started buying tomatoes that fight high blood pressure, and Americanshave been consuming soyengineered to produce high amounts of heart-healthy oils for a little over two years. Few people noticed these developments because, as scientists have said for a long time, the safety profile of a crop is not dictated by the breeding method that produced it. For all intents and purposes, it seems that food-safety regulators have done a reasonablejob of safeguarding public health against whatever hypothetical risks gene editing may pose.Credit: Karuchibe
But this has not stopped critics of genetic engineering from advocating for more federal oversight of CRISPR and othertechniquesused to make discrete changes to the genomes of plants, animals and other organisms we use for food or medicine. Over at The Conversation, a team of scientists recently made the case for tighter rules inCalling the latest gene technologies natural is a semantic distraction they must still be regulated.
Many scientists have defended gene editing, in part, by arguing that it simply mimics nature. A mutation that boosts the nutrient content of rice, for example, is the same whether it was induced by a plant breeder or some natural phenomenon. Indeed, the DNA of plants and animals we eatcontains untold numbersof harmless, naturally occurringmutations. But The Conversation authors will havenone of this:
Unfortunately, the risks from technology dont disappear by calling it natural Proponents of deregulation of gene technology use the naturalness argument to make their case. But we argue this is not a good basis for deciding whether a technology should be regulated.
They have written a very longpeer-reviewed articleoutlining a regulatory framework based on scale of use.The ideais that the more widely a technology is implemented, the greater risk it may pose to human health and the environment, which necessitates regulatory control points to ensure its safe use. Its an interesting proposal, but its plagued by several serious flaws.
The most significant issue with a scale-based regulatory approachis that its a reaction to risks that have never materialized. This isnt to say that a potentially harmful genetically engineered organism will never be commercialized. But if were going to upend our biotechnology regulatory framework, we need to do so based on real-world evidence. Some experts have actually argued, based on decades of safety data, that the US over-regulates biotech products. As biologist and ACSHadvisorDr. Henry Miller and legal scholar John Cohrssen wroterecently in Nature:
After 35 years of real-world experience with genetically engineered plants and microorganisms, and countless risk-assessment experiments, it is past time to reevaluate the rationale for, and the costs and benefits of, the case-by-case reviews of genetically engineered products now required by the US Environmental Protection Agency (EPA), US Department of Agriculture (USDA) and US Food and Drug Administration (FDA).
Real-world data aside for the moment, there are some theoretical problems with the scalabilitymodel as well. Theargument assumes thatrisks associated with gene editing proliferate as use of the technology expands, because each gene edit carries a certain level of risk. This is a false assumption, as plant geneticist Kevin Folta pointed out on a recentepisode of the podcastwe co-host (21 minute mark).
Scientists have a variety of tools with which to monitor and limit the effects of specific gene edits. For example,proteins known asanti-CRISPRs can be utilized to halt the gene-editing machinery so it makes only the changes we want it to. University of Toronto biochemist Karen Maxwell has explained how this couldwork in practice:
In genome editing applications, anti-CRISPRs may provide a valuable off switch for Cas9 activity for therapeutic uses and gene drives. One concern of CRISPR-Cas gene editing technology is the limited ability to control its activity after it has been delivered to the cell . which can lead to off-target mutations. Anti-CRISPRs can potentially be exploited to target Cas9 activity to particular tissues or organs, to particular points of the cell cycle, or to limit the amount of time it is active
Suffice it to say that these and other safeguards significantly alter the risk equation and weaken concerns about a gene-edits-gone-wild scenario. Parenthetically, scientists design these sorts of preventative measures as they developmoregenetic engineering applications for widespread use. This is why the wide variety of cars in production todayhave safety featuresthat would have been unheard of in years past.
To bolster their argument, The Conversation authors made the following analogy:
Imagine if other technologies with the capacity to harm were governed by resemblance to nature. Should we deregulate nuclear bombs because the natural decay chain of uranium-238 also produces heat, gamma radiation and alpha and beta particles? We inherently recognize the fallacy of this logic. The technology risk equation is more complicated than a supercilious its just like nature argument
If someone has to resort to this kind of rhetoric, the chances are excellent that their argument is weak. Fat Man and Little Boy,the bombs droppedon Japan in 1945, didnt destroy two cities because a nuclear physicist in New Mexico made a technical mistake. These weapons are designed to wreak havoc. Tomatoes bred to produce more of an amino acid, in contrast, are not.
The point of arguing that gene-editing techniques mimic natural processes isnt to assert that natural stuff is good; therefore, gene editing is also good. Instead, the point is to illustrate that inducing mutations in the genomes of plants and animals is not novel or uniquely risky. Even the overpriced products marketed as all-naturalhave been improvedby mutations resulting from many years of plant breeding.
Nonetheless, some scientistshave arguedthat reframing the gene-editing conversation in terms of risk vs benefit would be a smarter approach than making comparisons to nature. I agree with them, so lets start now. The benefits of employing gene editing to improve our food supply and treat disease far outweigh the potential risks, which we can mitigate. Very little about modern life is naturaland its time we all got over it.
Cameron J. English is the director of bio-sciences at theAmerican Council on Science and Health. Visithis websiteand follow ACSH on Twitter@ACSHorg
A version of this article was originally posted at theAmerican Council on Science and Healthand is reposted here with permission. The American Council on Science and Health can be found on Twitter@ACSHorg
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