Ronald Bailey at Reason analyzes a new anti-GM argument

Ronald Bailey from Reason Magazine has an article covering one of the more pernicious arguments against genetically modified foods:

Long time anti-biotech activist Jeremy Rifkin has come out in favor of a biotechnology technique. Should beleaguered biotechnologists break out the champagne and start celebrating? Not hardly. Earlier this week, Rifkin wrote an op/ed in the Washington Post in which he declared his support for marker assisted selection (MAS) for use in plant breeding. So far, so good.

MAS is a molecular technique in which researchers identify sections of DNA in a plant or animal located near a gene or genes that confer specific valuable traits. In plants, such traits might increase their resistance to drought or disease, or they might boost their productivity. Once a trait has been identified, researchers can trace it as they crossbreed the plants containing it with commercial varieties. Thus MAS makes it far easier for plant breeders to identify which of the crossbred plants carry the trait. That means that breeders don't have to plant the seedlings and then wait for them to grow up in the field before identifying which ones carry the sought-after new trait. MAS can cut the time to develop new commercial crop varieties in half.

Rifkin points to all of these advantages, but then declares that MAS has "made gene splicing and transgenic crops obsolete and a serious impediment to scientific progress." Whoa. Could that be true?

Plant geneticists and breeders don't agree. According to Alan McHughen, a plant biotechnologist at the University of California, Riverside, "The problem for Rifkin: MAS is not, as he suggests, an alternative to gene splicing (recombinant DNA or rDNA), but an adjunct. Both are powerful and useful tools that can be used together."

McHughen offers a real life example of how MAS and gene-splicing have been used to introduce disease resistance in rice. Many rice varieties have regularly been devastated by bacterial leaf blight. Fortunately, back in the 1970s researchers identified a blight-resistant species of wild rice native to Mali. Given the state of biotech then, it took years for the Xa21 gene that confers blight resistance to be identified. By the late 1990s, some California plant biotechnologists succeeded in using gene-splicing to insert the Xa21gene into commercial rice varieties to endow them with blight resistance. In 2003, Chinese plant breeders reported using MAS to identify and guide their efforts to successfully crossbreed a blight resistant rice variety with a productive commercial variety. Both are resistant to blight, but Rifkin wants to claim that one is a danger and the other is safe. Rifkin asserts that "With MAS, the breeding of new varieties always remain within a species, thus greatly reducing the risk of environmental harm and potential adverse health effects associated with genetically modified crops."

However, as McHughen points out, "The irony--if not stupidity--is that the resulting plant in each case is genetically identical. If one plant is safe, the other is equally safe. If one carries risks, the other carries the identical risks. Yet to Rifkin, the GE (genetically engineered) rice is so hazardous that it demands banning outright, and the other rice is the savior of sustainable agriculture."

Bailey goes on to point out that 1) no health risk has ever been identifed for any genetically modified food, 2) several have been identified for non-GM foods that were selectively bred, and 3) no scientist recognizes the inviolability of species that Rifkin is asserting. NATURE doesn't even recognize that kind of inviolability -- look at hybrid species and retroviruses. It is just maddening that someone would so arbitrarily ignore technologies that are not in substance different and that have the capacity to improve so many lives.

Read the whole thing.

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