Did you know? Browning in apples and other fruits happens when oxygen in the air reacts with phenols in the fruit’s flesh, causing melanin to form. Melanin is the same pigment produced in our skin when we tan!As Snow White knows, there’s nothing better than the juicy white flesh of a ripe apple. But there's nothing worse than the brown mushy stuff that begins to appear a few minutes after the first bite. What if every bite were as sweet and crisp as the first? Should we meddle with nature to suit our tastes? Is it even safe to do so?
A Canadian biotechnology company, Okanagan Specialty Fruits, has already produced an apple that doesn't brown. Browning in fruit is controlled by an enzyme called polyphenol oxidase (PPO). Biologists at Okanagan have found a way to turn off (or “silence”) the gene that makes PPO, creating an apple that won’t brown when it’s cut or bitten into. Okanagan calls its genetically modified (GM), non-browning variety “Arctic apples.” The company is currently trying to get approval to sell them in the U.S. and Canada.
|A side-by-side comparison of a "regular" apple (left) and an Arctic apple. According to the Okanagan Specialty Fruit website, "Arctic apples aren’t slow browning, they aren’t low browning – they are truly nonbrowning. An Arctic apple will decay naturally just like any other apple, but it will not turn brown from bruising, cutting or biting – not in minutes, hours or days." (Okanagan Specialty Fruit) |
Before hitting Canadian supermarket shelves, all GM foods need to be evaluated for health risks by Health Canada and for environmental risks by the Canadian Food Inspection Agency (CFIA). For Arctic apples, this process is currently underway. It typically takes a company like Okanagan seven to ten years to gather all the data it needs to demonstrate that its new food is as safe and nutritious as its non-GM siblings. As well as studying all the nutrients present in the new crop, researchers watch it grow, keeping an eye out for abnormalities that signal unwanted mutations. The new crop must also be tested to make sure it isn't toxic or allergenic. This can be done by examining the chemical structure of all the new proteins created by the plant, and by feeding the new food to rats or mice in the lab.
Did you know? Laboratory rats live up to 2 years and share a lot of similarities with humans in terms of metabolism. That's why researchers often use rats to study long-term health effects in a short period of time.These safety studies are carried out by the company developing the new food and are then evaluated by experts at Health Canada and the CFIA. Since companies want to protect their intellectual property, these results are not always made available to the rest of the scientific community. Of the studies that have been published, however, none provide definitive evidence of any health risks posed by GM foods currently on the market. This is good news for farmers who lose fewer crops due to drought, pests, and bruising when they use genetically modified crops. These crops could also benefit developing countries, where higher yields can help feed growing populations.
Of course, it is important to evaluate each new crop separately, since different foods raise different safety concerns depending on how they are created and the chemicals they might produce. While it is impossible to make blanket statements about the safety of genetically modified foods, sound scientific testing can help policy-makers figure out which ones are safe enough to grace our supermarket shelves. In the meantime, you can keep your eyes open for news on how the Arctic Apple is faring in its quality tests.
Find out more about genetically modified organisms by visiting the CurioCity Biotechnology Theme Page and the Agriculture and Biotechnology section of this website. Biotechnology and You (Okanagan Specialty Fruits)
http://www.okspecialtyfruits.com/science-and-safety Rat study sparks GM furor (Nature: International Weekly Journal of Science)
http://www.nature.com/news/rat-study-sparks-gm-furore-1.11471 Genetically Modified (GM) Foods and Other Novel Foods (Health Canada)
http://www.hc-sc.gc.ca/fn-an/gmf-agm/index-eng.php More about the regulatory process (Arctic Apples)
http://www.arcticapples.com/arctic-apples-story/regulatory-process 20 Questions on Genetically Modified Foods (World Health Organization)
Domingo, J.L., and J. Giné Bordonaba. 2011. A literature review on the safety assessment of genetically modified plants. Environment International. 37:734-742. Malarkey, T. 2003. Human health concerns with GM crops. Mutation Research. 544:217-221. Snell, C., et al. 2011. Assessment of the health impact of GM plant diets in long-term and multigenerational animal feeding trials: A literature review. Food and Chemical Toxicology. 50:1134-1148.