Humans have been manipulating the genetic code of plants for thousands of years. Early farmers adopted cross-breeding methods to modify various plants to produce more desirable traits. Traditional breeding techniques can take many years to develop the sought after changes, however, and often with mixed results. In the 1970s, agriculture was changed forever when scientists discovered a way to make faster and more specific modifications via direct DNA manipulation that exponentially sped new trait development while simultaneously eliminating the introduction of unwanted characteristics. Today, approximately 90% of corn, soybeans, and sugar beets sold on the global market are genetically engineered crops.
The man credited for establishing the modern science of genetics is Gregor Johann Mendell, a meteorologist, mathematician, and biologist that discovered how traits pass from plant and animal parents to offspring back in the mid-1800s. This new understanding created the potential for people to selectively breed crops and livestock. However, the breakthrough that led to today’s GMO technology didn’t occur until 1973, when Herbert Boyer and Stanley Cohen developed “recombinant DNA” technology, a method to very specifically cut out a gene from one organism and paste it into another. The two scientists transferred a gene that encodes antibiotic resistance from one strain of bacteria into another, bestowing antibiotic resistance upon the recipient. One year later, Rudolf Jaenisch and Beatrice Mintz utilized a similar procedure in animals, introducing foreign DNA into mouse embryos.
Controversy surrounding the new technology arose almost immediately as the public, government, and researchers began debating the possible ramifications of manipulating DNA. From mid-1974, an “unofficial” moratorium on genetic engineering projects was universally observed until the Asilomar Conference in 1975. Participants at Asilomar drew up voluntary guidelines to ensure the safety of recombinant DNA technology, freeing scientists to resume their research.
Still, lingering safety concerns and the push to develop rigorous safety standards would mean almost another 20 years before GMOs are approved for human consumption. The first commercial product using recombinant DNA technology was actually a synthetic insulin called Humulin. Pig and cattle pancreatic glands were previously the only way of producing insulin for human use. The first GM plants appeared in 1983 with antibiotic-resistant tobacco and petunia. However, it was 1990 before the first GM food crop was developed, the FlavrSavr tomato, and it took another four years for it to be approved for human consumption. Researchers at Calgene, a biotech company in California, developed the tomato to delay ripening and reduce rot. Despite initial commercial success, FlavrSavr was considered a failure due to is high production costs, though many attribute that to Calgene’s lack of agriculture production and shipping knowledge more than anything else. FlavrSavr tomatoes cost $10 per pound to produce, but were being sold for only $1.99 per pound at the market. Production was ceased when Monsanto acquired Calgene in 1996.
In the meantime, other biotech companies had begun developing GM crops to appeal to farmers, with features such as pest resistance and herbicide tolerance. The first pest-resistance gene to be isolated and used was from Bacillus thuringiensis (commonly known as “Bt”), a soil bacterium that naturally produces proteins that are toxic to certain insects. Genetically Engineered (GE) seeds were commercially introduced in the United States for major field crops in 1996, with adoption rates increasing rapidly in the years that followed.
Today, over 90% of U.S. corn, upland cotton, and soybeans are produced using GE varieties. Although other GE traits have been developed (such as virus and fungus resistance, drought resistance, and enhanced protein, oil, or vitamin content), herbicide tolerance (HT) and Bt traits are the most commonly used in U.S. crop production. According to an annual review of crop biotechnology produced by PG Economics, from 1996 to 2018, crop biotechnology has been responsible for the additional global production of +278 million metric tons of soybeans, +498 million metric tons of corn, +32.6 million metric of cotton lint, and +14 million metric tons of canola. Additionally, the report shows farmers who planted genetically modified (GM) crops increased their incomes by almost +$19 billion in 2018 and reduced carbon emissions by more than -50 billion pounds, or the equivalent of removing 15.3 million cars from the roads that year.
Looking toward the future, climate change and population growth are putting increased pressure on the agricultural industry to feed a hungry world. Biotechnology can help us develop new, more resilient crop varieties that are better able to survive these changing conditions. While controversy surrounding the technology is still very much alive, consumer acceptance does seem to be growing. Importantly, a recent survey by the Center for Food Integrity found that Gen Z and millennials tend to be more accepting of agricultural technology than their older counterparts and to see it as offering powerful solutions to humanity’s future food security. (Sources: FDA, MIT Review, Alliance for Science, Nature)