Commentary on New Technique For Modifying Plant Genes Developed -ScienceDaily (May 4, 2009)

http://www.sciencedaily.com/releases/2009/04/090429132233.htm

According to a recent Science Daily article, scientists have developed a genetic engineering tool that makes a model crop plant herbicide-resistant by making slighter, more subtle changes to its DNA. This new technique can help scientists modify plants more precisely and potentially reduce concerns about genetically modified organisms. The new method for gene modification involves a customized enzyme known as zinc finger nuclease (ZFN) that binds to specific DNA sequences, altering single genes at or near the binding site.

This new development, as indicated by the article, is revolutionary because it is the first major change to genetic modification since the 1980’s. Traditionally, genetic engineering of crops involves introducing foreign DNA into plant cell genome without knowing exactly where the DNA will be incorporated. There are several methods of delivering this foreign DNA, including the use of Agrobacterium tumefaciens and a particle gun. Agrobacterium tumefaciens is a bacterium that lives in the soil and “acts as a natural genetic engineer.”[1] It has a tumor-inducing(TI) plasmid which is a circular, doublestranded DNA molecule that can replicate independently of the agrobacterium’s genome. When the bacteria infects a plant cell, a segment of the Ti plasmid, T DNA, separates and incorporates itself into the host genome.[2] Scientists exploit this process by inserting desirable genes into the T DNA while ridding it of its cancer-causing properties.[3] Crop plant cells are exposed to the new recombinant bacteria, receive the foreign genes, and grow into modified plants. The particle gun method is popular for monocots (corn, wheat) which do not work with agrobacterium.[4] It involves microscopic pellets of gold or tungsten bathed in the foreign DNA.[5] The pellets are fired into the plant cells, leaving traces of DNA behind which can mix with the host DNA.

The article states that one of the main benefits is that the new ZFN technique may quell fears about the dangers of genetically modified foods in that it reduces the unknowns in the old method where genes are inserted randomly into the genome. However, I doubt that this new development will do much to settle the war over GM foods. It may help sway a few on the fence about GM crops, but most people will not be able to understand or differentiate between the new and old techniques. The fear over genetically modified foods is not rooted in logic or scientific proof but heavily politicized beliefs.

I’m not saying that we should not be cautious in embracing GM foods. The potential threats to biodiversity, the actual effectiveness of certain GM crops, and the regulation of crop biotechnology companies like Monsanto are all very important issues the public must continue to monitor. But think about the potential good biotech crops offer in the(perhaps somewhat distant) future. The latest developments in the GMO world involve tobacco plants that deliver therapeutic proteins[6], high protein rice[7], tomatoes that deliver vaccines[8], and more. Yes these will take many years to be available commercially, but they can play a part in treating the world’s sick and impoverished. Increased crop yields from GM crops will be key in the next Green Revolution.

Besides, whether or not the world is prepared for it, genetically modified foods are here to stay. An additional 1.3 million farmers planted 10.7 million new hectares of biotech crops including three new countries in 2008, according to the ISAAA brief Global Status of Commercialized Biotech/GM Crops 2008.[9] The U.S., China, India, and numerous other countries are adopting GM foods and seeing economic and environmental benefits. Europe cannot continue to avoid the reality of GM foods, as evidenced by the traces of GM corn even in non-GM shipments of soy to Europe.[10]

This article is just one example of the continuing advancements of the biotech industry and its increased skill in creating well designed, safe crops for the future. In relation to the current healthcare debate, GM foods in the future may prove to be helpful in providing extra nutrition or producing cheap, accessible vaccines for the public.

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[1] “Biotech Basics” Monsanto, 2001.

[2] Pamela Peters, “Transforming Plants: Basic Genetic Engineering Techniques” from "Biotechnology: A Guide to Genetic Engineering." Dubuque, IA: Wm. C. Brown Publishers, 1993. <http://www.accessexcellence.org/RC/AB/BA/Transforming_Plants.php>

[3] Ibid.

[4] “Biotech Basics” Monsanto, 2001.

[5] Ibid.

[6] “Tobacco Makes Medicine” Science Daily 4 May 2009. http://www.sciencedaily.com/releases/2009/03/090318211236.htm

[7] “New High Protein Rice Strain Developed” Science Daily 15 Jan 2008. http://www.sciencedaily.com/releases/2008/01/080114095753.htm

[8] Andy Coghlan, “Killer tomatoes attack human diseases” New Scientist 29 June 2009.

[9]“Crop Biotech Update” ISAA 2008. http://www.isaaa.org/kc/cropbiotechupdate/specialedition/2009/default.asp

[10] Paul Voosen, “Trade Chaos Looms as GM Crops Proliferate” Greenwire 2 Nov 2009 http://www.nytimes.com/gwire/2009/11/02/02greenwire-trade-chaos-looms-as-gm-crops-proliferate-98320.html?scp=1&sq=genetically%20modified&st=cse