The Past, Present, and Future of Genetically Modified Organisms

///The Past, Present, and Future of Genetically Modified Organisms

The Past, Present, and Future of Genetically Modified Organisms

2017-05-14T00:49:08-07:00 February 24th, 2017|Genetics|

By Rachel Hull

Author’s note

When I began my research for this piece, I was primarily interested in the controversy over the fairly new bill in the United States requiring labels on foods that contain genetically modified ingredients. Little did I know that as I was gathering my sources, a new GMO dispute would emerge, this one revolving around bioengineered non-browning apples. Thus I switched my focus from the bill to the arrival of these apples to stores across the U.S. — an arrival that means an investigation into the history and science behind genetically engineered food products is even timelier than I originally thought.

History in brief

In grocery stores nationwide this month, Arctic Apples are set to hit the shelves. These apples, produced by Okanagan Specialty Fruits (OSF), have been genetically modified so that they do not brown when their cells are ruptured, unlike all other apples currently on the market. A blog post on OSF’s Arctic Apples website provides an overview of the techniques the company used to create such apples; below the post, comments abound. The reactions to Arctic Apples in these comments range from “Wow, it is amazing what you can do with biotechnology these days” to “We don’t want our children to eat your poison!” [1]

Genetically modified organisms (GMOs) are no stranger to controversy. In 1975 — decades before the first GMOs were to appear in grocery stores — a hodgepodge group of scientists, lawyers, journalists, and government officials met to discuss recombinant DNA (rDNA) [2, 3]. This conference was prompted by recent scientific advancements pertaining to rDNA, which pieces together DNA strands from two different organisms. Though several other meetings had taken place before it, it was the 1975 conference that history would remember, as it set the groundwork for subsequent guidelines on rDNA research without wholly restricting such research [3, 4].

In the years following the conference, the realm of genetic engineering split in several directions. Some scientists saw rDNA’s potential to revolutionize medication, while others were more interested in its applications to the environment. The first patent for a GMO, issued in 1981, was in fact for a bacterium that could degrade complex hydrocarbons such as crude oil [5]. Around the same time, research on the correlation between the enzyme polygalacturonase (PG) and fruit softening was in its initial stages at Calgene, Inc. Researchers found that inserting an antisense copy of the gene that produces PG into tomatoes could delay their ripening. In 1994, the company introduced such tomatoes to the market under the name FLAVR SAVR tomatoes. Though demand for the tomatoes was high, the profits were slim due to the cost of making them, and public concern over their safety eventually knocked them out of grocery stores [6].

Despite this failure, GMO food crop research blazed ahead. By 1996, genetically modified crops covered more than 4.2 million acres of the planet [7]. That number had risen to 444 million by 2015 — the first year, in fact, that the global acreage decreased from one year to another [8].

More recent developments

GMOs were again thrust into the public arena in July of last year when then-president Barack Obama signed a bill requiring labels on genetically modified foods. The U.S. Department of Agriculture has until 2018 to iron out the details of the law, and food companies will be granted more time after that to comply with the new regulations. The companies will also have a range of GMO disclosure options: text, a symbol, a phone number or even a QR code directing consumers to more information. It is worth noting, however, that the law defines bioengineered food products as containing “genetic material.” This means that the GMOs most commonly found in stores — corn syrup and canola oil, for example — will likely be exempt because they are highly refined. In addition, the law’s language indicates that it will likely not apply to meat, poultry, or eggs [9, 10, 11].

        The federal law came about in response to the passage of more restrictive labeling laws in Vermont, Connecticut, and Maine [12]. These laws, in turn, stemmed partly from public uncertainty regarding the safety of GMOs, despite the general consensus in the scientific community that GMOs have not been shown to pose any serious health or environmental risks [13]. A 2016 U.S. survey, conducted as part of the Annenberg Science Knowledge survey project, found that 88 percent of participants supported mandatory labeling laws, and 91 percent said that people have the right to know if there are GMOs in their food. These opinions contrast sharply, however, with the fact that 58 percent said they have only a fair or poor understanding of GMOs; only 1 in 5 participants even knew that scientists have not found any evidence indicating that GMOs have adverse effects on human health [14].

The debut of Arctic Apples

Amidst this confusion, Arctic Apples entered the scene. Scientists have known for decades that in the presence of oxygen — which abounds when, say, someone bites or cuts an apple — the enzyme polyphenol oxidase (PPO) reacts with phenols in the apple cells, eventually resulting in brown pigmentation [1, 15]. It was the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia that developed the idea of using gene silencing techniques to inhibit PPO, though their research focused on potatoes rather than apples [16]. OSF licensed these techniques in 1997, spent years on research and development, and finally unveiled Arctic Apples in 2015 [16, 17].

        For Arctic Apples, a gene sequence called GEN-03 lies at the heart of the gene silencing process. GEN-03 is written such that in apples with the sequence, PPO expression is reduced dramatically [16]. OSF’s science team uses Agrobacterium tumefaciens, an organism often used for transformations in the biotechnology world, to introduce GEN-03 into the leaf tissue [18]. Attached to the GEN-03 sequence is a marker gene that produces the protein NPTII, which confers resistance to the antibiotic kanamycin; therefore, to ensure that a transformation was successful, scientists test the leaf tissue for kanamycin resistance [19]. If it passes this test, the tissue is allowed to grow into a plantlet, which is then grafted onto apple rootstock that will be planted and grow like a normal apple tree [18].

        Though some argue that non-browning apples are not a worthwhile endeavor, others point out that millions of pounds of apples are wasted each year because their brown pigmentation makes them less appealing to consumers [17, 20]. For its part, OSF adds that apples that brown enzymatically also degrade antioxidants and other nutrients, meaning Arctic Apples may be healthier than their traditional counterparts [21]. Early survey results indicated that 80 percent of consumers were interested in buying the apples once they were commercially available, but only time will tell their true success in the market [20].

It is a strange time for Arctic Apples to make their debut, as the new labeling law will apply to them [9]. The future of not only these apples, but GMOs in general, remains uncertain. It must be noted, however, that humans have been tampering with food crop genetics for thousands of years, beginning with farmers cross-breeding crops to end up with desirable hybrids [22]. In consideration of this fact, it seems likely that despite public bickering over GMOs, they will remain a part of life — at least in some capacity — for years to come. How about them apples?

       

References

  1. Arctic Apples. “How’d We ‘Make’ a Nonbrowning Apple?” Arctic Apples. Okanagan Specialty Fruits Inc. Web.
  2. Woolsey, G.L. “GMO Timeline: A History of Genetically Modified Foods.” Rosebud Magazine. Rosebud Magazine, 6 Sept. 2012. Web.
  3. Berg, Paul. “Meetings That Changed the World: Asilomar 1975: DNA Modification Secured.” Nature 455.7211 (2008): 290-91. Macmillan Publishers Limited, 17 Sept. 2008. Web.
  4. Berg, Paul, David Baltimore, Sydney Brenner, Richard O. Roblin, and Maxine F. Singer. “Summary Statement of the Asilomar Conference on Recombinant DNA Molecules.” Proceedings of the National Academy of Sciences 72.6 (1975): 1981-1984. Web.
  5. Chakrabarty, Ananda M. Microorganisms Having Multiple Compatible Degradative Energy-generating Plasmids and Preparation Thereof. General Electric Company, assignee. Patent 4,259,444. 31 Mar. 1981. Print.
  6. Bruening, G., and J.M. Lyons. “The Case of the FLAVR SAVR Tomato.” California Agriculture 54.4 (2000): 6-7. Web.
  7. James, Clive. ISAA Brief 51-2015: Executive Summary. Issue brief no. 51. International Service for the Acquisition of Agri-Biotech Applications. Web.
  8. Pollack, Andrew. “Acreage for Genetically Modified Crops Declined in 2015.” The New York Times. N.p., 16 Apr. 2016. Web.
  9. Amelinckx, Andrew. “What You Need To Know About the New GMO Labeling Law.” Modern Farmer. Modern Farmer Media, 8 Aug. 2016. Web.
  10. An Original Bill to Amend the Agricultural Marketing Act of 1946 to Require the Secretary of Agriculture to Establish a National Voluntary Labeling Standard for Bioengineered Foods, and for Other Purposes, S. 2609, 114th Cong. (2016). Print.
  11. United States Food and Drug Administration. “FDA/HHS Technical Assistance on Senate Agriculture Committee Draft Legislation to Establish a National Disclosure Standard for Bioengineered Foods.” FDA/HHS. 27 June 2016. Web.
  12. Becker, Benjamin. “Senate GMO Labeling Bill Stirs Controversy with FDA.” Labdoor Magazine. 12 July 2016. Web.
  13. Harvey, Chelsea. “People Want GMO Food Labeled — Which Is Pretty Much All They Know about GMOs.” The Washington Post. 21 July 2016. Web.
  14. Annenberg Public Policy Center of the University of Pennsylvania. ”Americans Support GMO Food Labels But Don’t Know Much About Safety of GM Foods.” APPC. 18 July 2016. Web.
  15. Nicolas, Jacques J., Florence C. Richard-Forget, Pascale M. Goupy, Marie-Josephe Amiot, and Serge Y. Aubert. “Enzymatic Browning Reactions in Apple and Apple Products.” Critical Reviews in Food Science and Nutrition 34.2 (1994): 109-57. Web.
  16. Arctic Apples. “PPO Silencing: How It Works.” Arctic Apples. Okanagan Specialty Fruits Inc. Web.
  17. Welsh, Jennifer. “We’ve Finally Solved the Biggest Problem with Apples.” Business Insider. 12 Nov. 2015. Web.
  18. Arctic Apples. “How We Introduce the Nonbrowning Trait in Arctic Apples.” Arctic Apples. Okanagan Specialty Fruits Inc. Web.
  19. Arctic Apples. “Exploring the Marker Gene Used in Arctic Apples.” Arctic Apples. Okanagan Specialty Fruits Inc. Web.
  20. Brock, Adrick. “The Arctic Apple: A GMO Fruit that Won’t Go Brown.” Modern Farmer. Modern Farmer Media, 23 Jan. 2014. Web.
  21. Arctic Apples. “Apple Nutrition Facts.” Arctic Apples. Okanagan Specialty Fruits Inc. Web.
  22. Bushak, Lecia. “A Brief History of Genetically Modified Organisms: From Prehistoric Breeding To Modern Biotechnology.” The Grapevine. Medical Daily, 22 July 2015. Web.

Edited by: Chantele, Wren, and Carly