What does the drug insulin have in common with cheese, Hawaiian papaya and a vegan burger? All were developed using genetic engineering, an approach established more than 40 years ago.
In the early 1970s, researchers in the San Francisco Bay Area demonstrated that it was possible to genetically engineer bacteria with a new trait. They showed that genes from different species could be cut and spliced together and that the new genes could be reproduced and expressed in the bacteria.
Human insulin, the first genetically engineered drug marketed (a human gene expressed in a microbe), has been used since 1982 for the treatment of diabetes, a disease affecting more than 9% of the US population. Genetically engineered insulin has replaced insulin produced by farm animals because of its lower cost and reduced allergenicity.
Cheese is made by coagulating milk with the addition of rennet to produce curds. The curds are separated from the liquid whey and then processed and matured to produce a wide variety of cheeses. The active ingredient of rennet is the enzyme chymosin. Until 1990, most rennet was produced from the stomachs of slaughtered newborn calves. Today, at a 10th of the 1990 cost, chymosin is produced through genetic engineering. Genetically engineered chymosin is distributed globally, with 80% to 90% of the hard cheeses in the United States and United Kingdom produced using genetically engineered chymosin.
Campaigns against genetically engineered crops reflect a general anxiety about plant genetics and a distrust of established institutions.
In the 1950s, the entire papaya production on the Island of Oahu was decimated by papaya ringspot virus, which causes ring spot symptoms on fruits and stunting of infected trees, creating a crisis for Hawaiian papaya farmers. In 1978, Dennis Gonsalves, a local Hawaiian, and his coworkers spliced a small snippet of DNA from a mild strain of the virus into the papaya genome. The genetically engineered papaya yielded 20 times more papaya than the non-genetically engineered variety when infected. By September 1999, 90% of the farmers had obtained genetically engineered papaya, and most had planted them.
Patrick Brown, founder of Impossible Foods, is building on advances in genetic engineering to shift the world’s population away from its reliance on meat, egg, and milk products. His team of researchers is isolating proteins and other nutrients from greens, potatoes, and grains to recreate the complex flavors of a hamburger. To give the burger the color and flavor of beef, the team decided to add leghemoglobin, a protein found in the root nodules of peas and other plants that form a symbiotic relationship with nitrogen-fixing bacteria. Leghemoglobin has close chemical and structural similarities to the hemoglobin found in animal blood, and, like hemoglobin, it is red. The team used genetic engineering to express the plant gene encoding leghemoglobin in yeast and added the isolated yeast-produced protein to the mix. When you bite this vegan burger, it oozes red.
Thirty-five years since the first genetically engineered medicine was commercialized and more than 20 years since the first genetically engineered crop was planted, applications of genetic engineering have proliferated. It has been used to engineer insect resistant corn and cotton, reducing the amount of chemical insecticides sprayed worldwide, created apples that do not brown easily and provided new tools to save the lives of impoverished children. During this time, there has not been a single verifiable case of harm to human health or the environment.
Every major scientific organization in the world has concluded the genetically engineered foods on the market are safe to eat . These are the same organizations that many of us trust when it comes to other important scientific issues such as climate change and the safety of vaccines.
Despite the record of safety and environmental benefits, the process of genetic engineering (often called “GMO”) still provokes controversy and sometimes, violent protests.
Campaigns against genetically engineered crops reflect a general anxiety about plant genetics and a distrust of established institutions. It is often difficult for consumers and policy makers to figure out how to differentiate high-quality scientific research from unsubstantiated rumors. Jim Holt, a writer for The New York Times Magazine, cites a survey indicating that less than 10% of adult Americans possess basic scientific literacy. For nonscientists, it may be the sheer difficulty of science and its remoteness from their daily activities “that make it seem alien and dangerous.”
It may be that improved access to science-based information on genetics, food, and farming can help consumers and policy makers make environmentally sound decisions. But cognitive science reveals that we are subjective about how we get our information, what we trust and believe, and how we feel about the facts we get. Feelings are an inescapable part of our perceptions, no matter how well informed we are.
So, how can we move forward? By the year 2100, the number of people on Earth is expected to increase to more than 11.2 billion people from the current 7.6 billion. If we don’t change eating habits or reduce food waste, we will need to produce more food in the next 50 years than we produced in the last 10,000 years . And we need to do this while minimizing environmental impacts.
According to David Ropeik, an expert on risk perception, “If we want to make the smartest possible choices, we need to challenge ourselves to go beyond what instinctively feels right and try to blend our feelings with a careful, thoughtful consideration of what might actually do us the most good.”
Featured Image Credit: “Papaya Fruit Cut In Half Cut Vitamins Eat” by Couleur. CC0 via Pixabay.