Humans have manipulated their environment since Homo sapien began to roam the Earth over 100,000 years ago. Over time, we have learned to optimize our existence on the planet through altering different natural surroundings – be it discovering fire, domesticating wild animals, and utilizing wood, stones, and metals as building materials to name a few. However, food remains nature’s most valuable commodity for humans, and like other aspects of nature we have been able to harness its power for maximum utility.
While humans have been modifying food crops for thousands of years, in the past 100 years advances in biotechnology have allowed us to manipulate nature’s bounty more than ever before through the rise of genetically modified organisms (GMOs). However, the rise of GMOs has fueled speculation and fear, raising ethical and health concerns for how we may be manipulating the food we all eat in ways we don’t understand.
One such controversial genetically modified crop is corn. Corn’s ability to grow easily and inexpensively along with an abundance of calories has placed it amongst the world’s most versatile and important crops. With the advent of this new technology, corn, amongst other crops, has undergone radical transformations yielding both tremendous benefits and serious risks. This paper will outline the history of human modification of food, the birth of genetic modification of crops through recombinant DNA, the specific biotechnology processes in altering crops, and finally a discussion of the promises and risks of genetically modified corn.
The History of GMOs
Humans began to transition out of a hunter-gatherer lifestyle into an agricultural based one around 10,000 years ago, and this agricultural lifestyle was the driving force of society up till only around 100-120 years ago. Till the advent of the industrial revolution, humans have spent millennia learning how to enhance the plants and animals around them to maximize their food yield. Those who raise concern over the recent genetic alteration of food ignore how all early domestication of crops was also genetic modification by breeding desirable traits in plants from the random mutations that would occur in each crop generation.
The selective crop breeding to produce yield of a certain size, color, shape etc. has been so drastic that most of our staple crops (including strawberries, wheat, cabbage and corn) aren’t even remotely similar to any of their ancestors in the wild and could in fact no longer survive now without human intervention and care (Parrott 2006).
The industrial revolution of the last century started to shape what today’s system of modern agriculture looks like. As more advanced machinery and technology was introduced into the field, we began to see improved seed distribution, mineral and synthetic fertilizers, and improved farming techniques. However, the industrial revolution was also occurring alongside another revolution – the beginning of molecular biology.
For years scientists had been sure a class of cellular molecules had to be coding all the individual traits they were seeing in organisms. It wasn’t until Oswald’s Avery’s hallmark experiments with Pneumococcus in the 1940s that identified those molecules as DNA (Hauserman 2013). As DNA continued to be characterized throughout the later half of the 20th century, the most important discovery for GMOs was that of recombinant DNA.
Recombinant DNA means the ability to extract genetic material from one organism, artificially introduce it into another organism, and replicate that organism and have it express the foreign genetic material. In 1971, Paul Berg was working at Stanford University during his landmark gene splicing experiment where he was able to slice a piece of Lambda virus DNA using restriction enzyme EcoRI and insert it into Simian Virus 40 which had been cut with the same restriction enzyme.
The two types of DNA were rejoined into a single circular loop and the first recombinant DNA (rDNA) was created (Chemical Heritage Foundation). Scientists Herbert Boyer and Stanley Cohen were able to build on this work by inserting this rDNA into another organism to see if the genetic contents were able to be expressed in a new host.
In 1973, the two created a recombinant DNA plasmid by inserting the genes for resistance to bacterial antibiotic tetracycline into a plasmid. The plasmid was then transformed into a bacterial culture of E.coli and the only colonies that survived when exposed to tetracycline were those that contained the plasmid (Chemical Heritage Foundation).
These experiments showed that genetic material could indeed be transferred between species. The result of Berger, Boyer and Cohen’s work has been nothing short of a scientific revolution in the last 40 years – we now can select traits we prefer from different organisms from different species and express them in something entirely different. The agriculture industry was one of the primary beneficiaries of this breakthrough.
In 1988, the world’s first genetically modified crop was created. Recombinant genes resistant to the herbicide had successfully been inserted into soybean. The insertion of a single gene which produced an alternate enzyme involved in aromatic amino acid biosynthesis made soybean tolerant to the herbicide glyphosphate (Chassy 2007).
Herbicide tolerant soybeans transformed the market for soybean production, farmers now had a labor efficient, environmentally safe and inexpensive way to control weeds. Genetically engineered soybean was such a success that 93% of the world’s soybeans are now grown this way (Shetterly 2013). The success with soybean launched a cascading snowfall as scientists around the world rushed to patent dozens of genetically modified seeds for different crops through the mid to late 90s.
Over this last decade, genetically modified crops have been planted on more than a billionacres across the world (Chassy 2007). It’s estimated that these new techniques have brought farmers around the world an additional $27 billion in revenue and reduced pesticide use by 224 million kg (Chassy 2007). As the boom set off for GMO’s after the success of soybean, one company emerged as a clear leader in the industry of transgenic crops – Monsanto Company.
Five Steps to Monsanto’s Secret Sauce
The Monsanto Company was founded back in 1901 as a chemical company in St. Louis, Missouri and produced a variety of different products used through World War I, World War II and the post-War era. Monsanto became a player in the agricultural biotech industry in 1985 when it acquired G.D. Searle & Company and put its foot in the door with agriculture and animal/plant health.
Eleven years later, Monsanto purchased Agracetus to begin producing transgenic cotton, soybean and peanuts and proceeded then to buy out DEKALB, Cargill and Seminis to become the world’s largest seed company it is today (Bravo 2014). Monsanto’s most famous product is Roundup herbicide. This became the most used herbicide in the United States till reports emerged of its potential toxicity and possibility of containing carcinogenic material (Bravo 2014).
While their herbicide remains controversial, their technical expertise in seed modification is tough to rival. Using these five steps, Monsanto has been able to pioneer the development of almost every major genetically modified crop on the planet.
First, find a new trait. You can’t produce a genetically modified organism without identifying the trait you want the plant to have, and then finding what other organism already possess it. This process involves hundreds of thousands of experiments to determine what specific gene is in involved in which process and how it can affect the overall trait you’re hoping to select for.
Second, extract the gene. Monsanto engineers have developed proprietary technology called a “chipper” that uses high powered cameras and object-recognition algorithms able to shave off just a tiny piece of a seed, analyze it with genome mapping technology and isolate the particular gene of interest (Boyle 2011).
Third is trait insertion. Monsanto has developed what’s known as a “gene gun” which is a .22 caliber charge that fires a metal particle coated with DNA into plant tissue and is able to insert foreign DNA into the host crop genome that way. Recently a new technique requires placing the seed under incredible amounts of stress (heat, pH, nutrient starvation) and exposes is to a bug Agrobacterium tumefaciens to insert new proteins into its chromosome (Boyle 2011).
Fourth is the growth chamber. In massive growth chambers, seedlings are tested drought tolerance, salt tolerance, pest and disease resistance, etc.
Finally, the newly prepared seeds are planted. Monsanto provides very specific instructions regarding plant spacing, water and fertilizer use and plant population. Once your seed is planted, your genetically modified organism is ready to grow.
The Corn Revolution
Though Monsanto has had success with many GMO crops, the story for genetically modified corn is more complex. Corn, more formally known as maize, was one of the first crops in history to be domesticated. Humans learned early on how to cross-pollinate a scraggly grass called teosinte which contains minute fruitcases into the juicy corn kernels we grow today (Gewin 2003). In fact, the bright yellow corn husks we think of have never existed in the wild; they are entirely a product of selective breeding over thousands of years.
The origins of its domestication begin in Mexico 9,000 years ago where it spread through the Americas as a staple crop capable of being able to be produced quickly and inexpensively. These capabilities make corn one of the most widely grown products in world; in fact, the United States is the world’s largest producer and exporter of corn (Shetterly 2013). Accounting for more than 95% of the US’s total field grain production, the US pumps out corn from over 90 million acres of corn fields, laying mostly in America’s heartland.
Corn remains one of our most productive crops in terms of how many different products are corn derivatives. From the husk to the kernel, there are over 100 different corn byproducts. The most common we see are products like corn starch, corn syrup and corn oil. There are a range of other dietary by products most notably in cereals and baking mixes but also in more obscure products such as ice cream, chewing gum and coffee (GSMC). In fact genetically modified corn is found in 70% of the processed food supply (Gewin 2003).
Corn byproducts extend into non-dietary fields as well, turning up in adhesives, paper cups, toothpaste and medicines as well as the use of corn in ethanol production(GSMC). While dry-milling and wet-milling operations use fermentation to extract ethanol from corn, scientists have begun to genetically modify corn itself to produce ethanol. The biotech company Syngenta has produced a genetically engineered corn that contains a synthetic microbial amylase (extracted from microbes near ocean hot-water vents) which is able to break down corn starch into sugar more easily (Pollack 2011).
Given the broad use of corn and corn products, its understandable why producers were eager to experiment with genetic modification to massively scale up its production. One of Monsanto’s first modifications to corn was using Bt technology and the rise of Bt-corn.
Bt stands for Bacillus thuringienis which is a soil bacterium that produces several crystal proteins that destroy the gut of invading crop pests (Gewin 2003). Several of these crystal (cry) proteins were engineered into corn to provide innate herbicidal properties and have been planted widely. It is hard to argue with the benefits that Bt-corn, along with a range of other Bt-crops, has brought to farmers.
Not only has pesticide use has dropped by 50%, but certain industries like Alabama’s cotton fields and Hawaii’s papaya groves have been single handedly saved by Bt-crops against cotton bollworm infestations and the papaya ringspot virus. Moreover, the International Council for Science (ISCSU) has found that Bt-crops have lower levels of carcinogenic mycotoxins produced by fungi because there are fewer insect holes in plant tissue now.
While corn seems like a relative success, several risks remain. The concern today is that this broad-scale planting of Bt-corn will render the toxin ineffective over time as pests will grow resistant to the secreted toxin.
The Environmental Protection Agency is so afraid of Bt resistant pests that they’ve required 20% of Bt-corn fields also be planted with non Bt-corn so to slow the rate of pest resistance. More alarmingly is the risk of gene flow to other species. When pollen and seeds move in the environment through air/animals, it can transmit these new genetic traits to close by crops or other relatives through horizontal gene transfer.
The fear is that if these new seeds spread into the wild, they will have a competitive advantage over the local organisms and will displace valuable genetic diversity (Gewin 2003). Instances of this have already occurred in western Europe, where genetically modified sunflowers completely took over the ecosystem near a farm and in Mexico where modified corn replaced all the local plants near a farm. Because of their ability to out compete the local flora and fauna in terms of nutrient utilization and insect protection, Mexico has tentatively banned transgenic corn being planted in its fields (Gewin 2003).
Despite the risks, it seems unlikely that the GMO boom will bust any time soon. The value added from genetically modifying our staple food crops have simply paid too large of dividends to curtail all planting and development of potentially problematic crops. While the risks posed by GMO’s are seemingly real, there is simply not enough long-term data to conclude they are riskier (Gewin 2003).
Humans are not unfamiliar with taking these kinds of risks with their food however. For millennia we have been selectively breeding and manipulating our staple food crops to produce the yield we desire. This is simply another chapter in our ongoing quest to conform nature’s products. The discovery of recombinant DNA methods along with the advent of new technology which is allowing companies like Monsanto to be able to identify novel traits, isolate them, insert them into crops and plant them around the world is allowing for one of the greatest agricultural booms in human history.
Never before have we produced as much food as we are now (Chassy 2007) despite growing populations, shrinking arable land and depleted resources, and all of this can be attributed to the brilliant scientists who’ve been able to maximize the power of a single seed.
Given that there is currently harsh reaction to some governments already to GMO’s, its inevitable that the wheels of innovation will continue to turn to enhance modified seeds more than they already are to solve these problems. As with any new revolutionary technology, government regulation should continue to stay in place to ensure the long-term sustainability of GMO’s. In the end they may have no choice, genetically modified organisms are here to stay.
1- Boyle , Rebeca. 2011. “HOW TO GENETICALLY MODIFY A SEED, STEP BY STEP”, http://www.popsci.com/science/article/2011-01/life-cycle-genetically-modified-seed.
2 – Bravo, Kristina. 2014. “Here’s How the World’s Largest Biotech Company Came to Be”, http://www.takepart.com/article/2014/03/27/monsanto-timeline.
3 – Chassy, Bruce. 2007. “The History and Future of GMOs in Food and Agriculture”, http://www.researchgate.net/publication/249300545_The_History_and_Future_of_GMOs_in_Food_and_Agriculture
4 – Chemical Heritage Foundation. No Date. “Paul Berg, Herbert W. Boyer, and Stanley N. Cohen”, http://www.chemheritage.org/discover/online-resources/chemistry-in-history/themes/pharmaceuticals/preserving-health-with-biotechnology/berg-boyer-cohen.aspx.
5 – Gewin, Virgina. 2003. “Genetically Modified Corn – Environmental Benefits and Risks”, http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0000008
6 – Great Smokies Medical Center. No Date. “Sources of Corn and Corn By-Products”, http://www.gsmcweb.com/sources-of-corn-and-corn-by-products/.
7 – Hauserman, Samantha. 2013. “Oswald Theodore Avery”, https://embryo.asu.edu/pages/oswald-theodore-avery-1877-1955
8 – Parrot, W. 2006. “The nature of change: Towards sensible regulation of transgenic crops based on lessons from plant breeding, biotechnology, and genomics”, Proceedings from the 17th National Agricultural Biotechnology Council.
9 – Pollack, Andrew. “US Approves Corn Modified For Ethanol”, http://www.nytimes.com/2011/02/12/business/12corn.html
10 – Shetterly, Caitlin. 2013. “The Bad Seed: The Health Risks of Genetically Modified Corn”, http://www.elle.com/beauty/health-fitness/advice/a12574/allergy-to-genetically-modified-corn/
About The Author
Chetan Hebbale is currently a graduate student at the Johns Hopkins School of Advanced International Studies (SAIS) in Washington, D.C. focused on international economics, climate change, and sustainability.
Prior to this, he spent over 4 years at Deloitte Consulting working on technology and strategy projects at the CDC and U.S. Treasury Department.
He is a native of Atlanta, GA and attended the University of Georgia.