Good Gene – Bad Gene: When GMOs Succeed and When They Don’t

As we saw in a previous post, genetic engineering has recently been successful in greatly accelerating the development of vaccines for COVID-19. Genetically engineered crops, which date back about 30 years, have also scored a number of successes, but there have also been some notable failures.

To some environmentalists, tinkering with a food plant’s genes conjures up pictures of “Frankenfoods,” evocative of the monster created by the fictional mad scientist Frankenstein. But such irrational fears over food safety and the planet’s ecology, aggravated in the past by the cavalier attitude of agribusiness companies, are a rejection of science.

The clash between environmental activists and the agricultural behemoths is epitomized by the success story of golden rice. Golden rice is genetically modified to contain beta-carotene, a naturally occurring pigment that produces vitamin A in the human body and imbues the grain with a characteristic yellow color. The GMO (genetically modified organism) has been developed as the answer to vitamin A deficiency in many parts of Asia and Africa, where millions of poor children die or go blind each year from weakened immune systems caused by a lack of the vitamin.

But as soon as Swiss plant geneticist Ingo Potrykus and German biologist Peter Beyer triumphed in splicing the two necessary genes – one from daffodils, one from a bacterium – into rice, widespread hostility erupted, despite a wave of publicity about their accomplishment and a feature article in Time magazine in 2000.  

Golden rice was dismissed as “fool’s gold” by Greenpeace, who claimed that a person would have to eat about 9 kilograms (20 pounds) of cooked golden rice per day to meet the daily requirement for vitamin A. However, this far-fetched claim was repudiated by the subsequent development, reported in 2005, of an improved golden rice with 20 times as much vitamin A-generating beta-carotene. Other detractors saw the genetic engineering feat simply as a Trojan horse, as a vehicle for launching other more profitable GMO crops in the developing world.

Many further barriers lay in the two scientists’ path. These included bomb threats against Potrykus, necessitating construction of a bombproof greenhouse; obtaining free licenses to 70 patents belonging to 32 different companies and universities that the discovery had potentially infringed on; and crossbreeding required to insert the magic daffodil and bacterium genes into suitable varieties of rice, research conducted at the nonprofit IRRI (International Rice Research Institute) in the Philippines.

Nonetheless, in 2018, four countries – Australia, New Zealand, Canada and the U.S. – finally approved golden rice. The U.S. FDA (Food and Drug Administration) has granted the biofortified food its prestigious “GRAS (generally recognized as safe)” status. IRRI applied for approvals in rich countries initially, in order to avoid trade disruptions arising from small quantities of GMO rice finding their way into non-GMO rice sold to other countries.

An example of a GMO food that never made it to market is a soybean containing a gene from Brazil nuts. Seed supplier Pioneer Hi-Bred International wanted to bolster the nutritional content of its soy-based animal feeds, which must normally be supplemented with an amino acid called methionine to promote adequate growth of the feeding animals. Because the Brazil-nut protein 2S albumin is very rich in methionine, Pioneer planned to splice the 2S albumin gene into the soybean genome.  

But mindful that Brazil nuts can cause strong allergic reactions in humans – though the specific allergen was previously unknown – and that soybeans intended for animals can’t easily be separated from those destined for human consumption, the company commissioned testing of its transgenic soybeans for allergenicity.  

Sure enough, 2S albumin was found to be not only a human allergen but also present in the genetically altered soybeans, revealing that genetic engineering can indeed transfer food allergens from one plant to another. The positive test results, reported in 1996, would have required Pioneer to label its new product for sale in the U.S., under the FDA protocol for allergy testing in transgenic plants. Instead, the company dropped its marketing plans for the soybeans.

Another example of a potential GMO food that didn’t come to fruition is potatoes genetically engineered to produce their own pesticide. In this case, the idea was to make potatoes pest resistant via a gene borrowed from that harbinger of spring, the snowdrop flower. Despite its delicate appearance, the flower harbors a type of sugar-bearing protein known as a lectin that is toxic to certain kinds of preying insect.

A major furor erupted in the late 1990s over research on laboratory rats fed with lectin-modified transgenic potatoes, and claims by the researcher that the GMO potatoes stunted the rats’ growth and degraded their immune systems. But controversy over a scientific review of the research that found the experiments were invalid put a stop to any further development of potatoes engineered with the snowdrop gene. Today, the only GMO potato approved for human consumption is a nonbruising variety.

Next: How Near-Saturation of CO2 Limits Future Global Warming

Science vs Politics: The Precautionary Principle

Greatly intensifying the attack on modern science is invocation of the precautionary principle – a concept developed by 20th-century environmental activists. Targeted at decision making when the available scientific evidence about a potential environmental or health threat is highly uncertain, the precautionary principle has been used to justify a number of environmental policies and laws around the globe. Unfortunately for science, the principle has also been used to support political action on alleged hazards, in cases where there’s little or no evidence for those hazards.

The origins of the precautionary principle can be traced to the application in the early 1970s of the German principle of “Vorsorge” or foresight, based on the belief that environmental damage can be avoided by careful forward planning. The “Vorsorgeprinzip” became the foundation for German environmental law and policies in areas such as acid rain, pollution and global warming. The principle reflects the old adage that “it’s better to be safe than sorry,” and can be regarded as a restatement of the ancient Hippocratic oath in medicine, “First, do no harm.”

Formally, the precautionary principle can be stated as:

When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.

But in spite of its noble intentions, the precautionary principle in practice is based far more on political considerations than on science. It’s the “not fully established scientifically” statement that both embraces the principle involved and, at the same time, leaves it open to manipulation and subversion of science.

A notable example of the intrusion of precautionary principle politics into science is the bans on GMO (genetically modified organism) crops by more than half the countries in the European Union. The bans stem from the widespread, fear-based belief that eating genetically altered foods is unsafe, despite the lack of any scientific evidence that GMOs have ever caused harm to a human.

In a 2016 study by the U.S. NAS (National Academy of Sciences, Engineering and Medicine), no substantial evidence was found that the risk to human health was any different for current GMO crops on the market than for their traditionally crossbred counterparts. This conclusion came from epidemiological studies conducted in the U.S. and Canada, where the population has consumed GMO foods since the late 1990s, and similar studies in the UK and Europe, where very few GMO foods are eaten.

The precautionary principle also underlies the UNFCCC (UN Framework Convention on Climate Change), the 1992 treaty that formed the basis for all subsequent political action on global warming. In another post, I’ve discussed the lack of empirical scientific evidence for the narrative of catastrophic anthropogenic (human-caused) climate change. Yet Irrational fear of disastrous consequences of global warming pushes activists to invoke the precautionary principle in order to justify unnecessary, expensive remedies such as those embodied in the Paris Agreement or the Green New Deal.

One of the biggest issues with the precautionary principle is that it essentially advocates risk avoidance. But risk avoidance carries its own risks.

Dangers, great and small, are an accepted part of everyday life. We accept the risk, for example, of being killed or badly injured while traveling on the roads because the risk is outweighed by the convenience of getting to our destination quickly, or by our desire to have fresh food available at the supermarket. Applying the precautionary principle would mean, in addition to the safety measures already in place, reducing all speed limits to 10 mph or less – a clearly impractical solution that would take us back to horse-and-buggy days.  

Another, real-life example of an unintended consequence of the precautionary principle is what happened in Fukushima, Japan in the aftermath of the nuclear accident triggered by a massive earthquake and tsunami in 2011. As described by the authors of a recent discussion paper, Japan’s shutdown of nuclear power production as a safety measure and its replacement by fossil-fueled power raised electricity prices by as much as 38%, decreasing consumption of electricity, especially for heating during cold winters. This had a devastating effect: in the authors’ words,

“Our estimated increase in mortality from higher electricity prices significantly outweighs the mortality from the accident itself, suggesting the decision to cease nuclear production caused more harm than good.”

Adherence to the precautionary principle can also stifle innovation and act as a barrier to technological development. In the worst case, an advantageous technology can be banned because of its potentially negative impact, leaving its positive benefits unrealized. This could well be the case for GMOs. The more than 30 nations that have banned the growing of genetically engineered crops may be shutting themselves off from the promise of producing cheaper and more nutritious food.

The precautionary principle pits science against politics. In an ideal world, the conflict between the two would be resolved wisely. As things are, however, science is often subjugated to the needs and whims of policy makers.

Next: Challenges to the CO₂ Global Warming Hypothesis: (1) A New Take on the Carbon Cycle

On Science Skeptics and Deniers

Do all climate change skeptics also question the theory of evolution? Do anti-vaccinationists also believe that GMO foods are unsafe? As we’ll see in this post, scientific skepticism and “science denial” are much more nuanced than most people think.

To begin with, scientific skeptics on hot-button issues such as climate change, vaccination and GMOs (genetically modified organisms) are often linked together as anti-science deniers. But the simplistic notion that skeptics and deniers are one and the same – the stance taken by the mainstream media – is mistaken. And the evidence shows that skeptics or deniers in one area of science aren’t necessarily so in other areas.

The split between outright deniers of the science and skeptics who merely question some of it varies markedly, surveys show, from approximately twice as many deniers as skeptics on evolution to about half as many deniers compared to skeptics on climate change.

In evolution, approximately 32% of the American public are creationists who deny Darwin’s theory of evolution entirely, while another 14% are skeptical of the theory. In climate change, the numbers are reversed with about 19% denying any human role in global warming, and a much larger 35% (averaged from here and here) accepting a human contribution but being skeptical about its magnitude. In GMOs, on the other hand, the percentages of skeptics and deniers are about the same.

The surveys also reveal that anti-science skepticism or denial don’t carry over from one issue to another. For example, only about 65% of evolutionary skeptics or deniers are also climate change skeptics or deniers: the remaining 35% who doubt or reject evolution believe in the climate change narrative of largely human-caused warming. So the two groups of skeptics or deniers don’t consist of the same individuals, although there is some overlap.

In the case of GMO foods, approximately equal percentages of the public reject the consensus among scientists that GMOs are safe to eat, and are skeptical about climate change. Once more, however, the two groups don’t consist of the same people. And, even though most U.S. farmers accept the consensus on the safety of GMO crops but are climate change skeptics, there are environmentalists who are GMO deniers or skeptics but accept the prevailing belief on climate change. Prince Charles is a well-known example of the latter.

Social scientists who study such surveys have identified two main influences on scientific skepticism and denial: religion and politics. As we might expect, opinions about evolution are strongly tied to religious identity, practice and belief. And, while Evangelicals are much more likely to be skeptical about climate change than those with no religious affiliation, climate skepticism overall seems to be driven more by politics – specifically, political conservatism – than by religion.

In the political sphere, U.S. Democrats are more inclined than Republicans to believe that human actions are the cause of global warming, that the theory of evolution is valid, and that GMO foods are safe to eat. However, other factors influence the perception of GMO food safety, such as corporate control of food production and any government intervention. Variables like demographics and education come into the picture too, in determining skeptical attitudes on all issues.

Lastly, a striking aspect of skepticism and denial in contemporary science is the gap in opinion between scientists and the general public. Although skepticism is an important element of the scientific method, a far larger percentage of the population in general question the prevailing wisdom on scientific issues than do scientists, with the possible exception of climate change. The precise reasons for this gap are complex according to a recent study, and include religious and political influences as well as differences in cognitive functioning and in education. While scientists may possess more knowledge of science, the public may exhibit more common sense.

Next week: Use and Misuse of the Law in Science

When No Evidence Is Evidence: GMO Food Safety

The twin hallmarks of genuine science are empirical evidence and logic. But in the case of foods containing GMOs (genetically modified organisms), it’s the absence of evidence to the contrary that provides the most convincing testament to the safety of GMO foods. Although almost 40% of the public in the U.S. and UK remain skeptical, there simply isn’t any evidence to date that GMOs are deadly or even unhealthy for humans.

Absence of evidence doesn’t prove that GMO foods are safe beyond all possible doubt, of course. Such proof is impossible in practice, as harmful effects from some as-yet unknown GMO plant can’t be categorically ruled out. But a committee of the U.S. NAS (National Academy of Sciences, Engineering and Medicine) undertook a study in 2016 to examine any negative effects as well as potential benefits of both currently commercialized and future GMO crops.

The study authors found no substantial evidence that the risk to human health was any different for current GMO crops on the market than for their traditionally crossbred counterparts. Crossbreeding or artificial hybridization refers to the conventional form of plant breeding, first developed in the 18th century and continually refined since then, which revolutionized agriculture before genetic engineering came on the scene in the 1970s. The evidence evaluated in the study included presentations by 80 people with diverse expertise on GMO crops; hundreds of comments and documents from individuals and organizations; and an extensive survey by the committee of published scientific papers.

The committee reexamined the results of several types of testing conducted in the past to evaluate genetically engineered crops and the foods derived from them. Although they found that many animal-feeding studies weren’t optimal, the large number of such experimental studies provided “reasonable evidence” that eating GMO foods didn’t harm animals (typically rodents). This conclusion was reinforced by long-term data on livestock health before and after GMO feed crops were introduced.

Two other informative tests involved analyzing the composition of GMO plants and testing for allergens. The NAS study found that while there were differences in the nutrient and chemical compositions of GMO plants compared to similar non-GMO varieties, the differences fell within the range of natural variation for non-GMO crops. 

In the case of specific health problems such as allergies or cancer possibly caused by eating genetically modified foods, the committee relied on epidemiological studies, since long-term randomized controlled trials have never been carried out. The results showed no difference between studies conducted in the U.S. and Canada, where the population has consumed GMO foods since the late 1990s, and similar studies in the UK and Europe, where very few GMO foods are eaten. The committee acknowledged, however, that biases may exist in the epidemiological data available on certain health problems.

The NAS report also recommended a tiered approach to future safety testing of GMOs. The recommendation was to use newly available DNA analysis technologies to evaluate the risks to human health or to the environment of a plant –  grown by either conventional hybridization or genetic engineering – and then to do safety testing only on those plant varieties that show signs of potential hazards.

While there is documentation that the NAS committee listened to both sides of the GMO debate and made an honest attempt to evaluate the available evidence fairly, this hasn’t always been so in other NAS studies. Just as politics have interfered in the debate over Roundup and cancer, as discussed in last week’s post, the NAS has been accused of substituting politics for science. Further accusations include insufficient attention to conflicts of interest among committee and panel members, and even turning a blind eye to scientific misconduct (including falsification of data). Misconduct is an issue I’ll return to in future posts.

Next week: What Intelligent Design Fails to Understand About Evolution

Politics Clashes with Science over Glyphosate and Cancer

Nothing exemplifies the attack on science more than its subversion to politics. The intrusion of political forces into the scientific sphere has distorted the debates over dietary fat, climate change, GMO crops and other controversial topics. Particularly contentious at present is the charge that the weedkiller glyphosate causes cancer, an allegation that’s behind thousands of U.S. lawsuits filed by cancer victims against glyphosate manufacturer Monsanto. The victims, who suffer from non-Hodgkin’s lymphoma, claim the cancer was caused by spraying the company’s glyphosate-based Roundup herbicide.

Best-seller Roundup has been used since 1974 to kill weeds in more than 100 food crops as well as greenhouses, aquatic areas, and residential parks and gardens. It became an especially profitable product for Monsanto in 1996 after the agricultural behemoth introduced Roundup Ready seeds, which are genetically engineered to make crop plants resistant to the herbicide; the revolutionary advance meant that farmers could now use Roundup to kill weeds while the crop was growing, instead of only before planting.

The carcinogenic potential of glyphosate has been evaluated several times in the U.S. by the EPA (Environmental Protection Agency), and in Europe by the EFSA (European Food Safety Authority) and the ECHA (European Chemicals Agency). While all these evaluations concluded that glyphosate was unlikely to be carcinogenic to humans, the IARC (International Agency for Research on Cancer) shocked the world in 2015 by classifying glyphosate as a potential carcinogen. It’s the IARC assessment that underpins the multimillion-dollar mass litigation against Monsanto.

So who’s right? The various government agencies in the U.S. and Europe that see no problem in continuing to use Roundup, or the WHO (World Health Organization)’s IARC? Both camps maintain that the scientific evidence is on their side.

The dispute is an all-too-common example of how politics is invading science. As reported by Reuters last year, the IARC made significant changes between the original draft of its 2015 monograph on glyphosate and the published version. Although it’s not unusual for a final agency report to differ from the draft, what stands out in this case is that the principal changes were the deletion of all statements and findings – and there were many – contrary to the IARC’s ultimate conclusion that glyphosate probably causes cancer.

The agency refuses to say who made the changes or why. If such secrecy alone were not enough to arouse suspicion, Reuters found 10 significant alterations to the draft chapter on animal studies – the very chapter that in the final report provided “sufficient evidence" that glyphosate causes cancer in animals. The draft chapter had reported the conclusions of multiple studies finding no link at all between glyphosate and cancer in laboratory animals. But the final report concluded exactly the opposite.

That the changes to the IARC report were politically rather than scientifically motivated is reinforced by the EPA’s finding that glyphosate poses no carcinogenic risk to humans. This conclusion was also reached by the EFSA, the ECHA and the UN’s FAO (Food and Agriculture Organization) – despite the EFSA and ECHA, like other European agencies, being more conservative and pro-environment than their U.S. counterparts. Not surprisingly, the environmentally activist organization Greenpeace has called the EFSA report faulting the IARC declaration “a whitewash.”

By far the greatest amount of scientific data on the possible human carcinogenicity of glyphosate comes from a 2005 study of 85,279 American farmers and their spouses. The so-called AHS (Agricultural Health Study) included epidemiological, animal carcinogenicity, and genotoxicity investigations to elucidate the carcinogenic potential of Roundup products.

Both the EPA and the IARC utilized the AHS data in their recent, conflicting evaluations of glyphosate. However, the IARC monograph also included a number of “low-quality” studies that the EPA elected to omit. Although this may seem arbitrary on the EPA’s part, the studies omitted by the EPA lacked, for example, information on glyphosate exposure of individual subjects. Such shortcomings are important in light of the current reproducibility crisis in the biomedical sciences: up to 90% of published findings in some areas of biomedicine can’t be replicated. The inclusion of scientifically inferior data by the IARC strongly suggests political interference in the scientific process.

Of six specific studies that investigated the association between glyphosate exposure and non-Hodgkin’s lymphoma – the possible linkage at issue in the mass lawsuits – the EPA stated that “a conclusion … cannot be determined based on the available data.” Nevertheless, for cancer overall, the EPA report found the strongest support for an assessment of glyphosate exposure as “not likely to be carcinogenic to humans,” which is the weakest of five EPA risk classifications on cancer.

Meanwhile, the jury in the first trial of the Roundup litigation ruled on August 10 that Monsanto’s weedkiller was a substantial contributing factor in causing non-Hodgkin’s lymphoma and ordered the company to pay $289 million in damages, a figure since reduced to $78 million on appeal. With further trials scheduled in 2019, only time will tell who is right about the science.

Next week: When No Evidence Is Evidence: GMO Food Safety