Mexico's transgenic maize under fire

Experimental planting scheme has insufficient controls to prevent gene flow to native crops, critcs say. by: Rex Dalton http://www.nature.com/news/2009/091125/full/462404a.html Mexico doesn't have an adequate system to monitor or protect natural maize (corn) varieties from transgenes, say prominent scientists concerned about the experimental planting of genetically modified crops. Activists question Mexico's transgenic maize. M. TOVAR/AP PHOTOIn the past month, Monsanto and Dow AgriSciences have received government permission to plant transgenic maize across 24 plots, covering a total of nearly 13 hectares, in the northern states of Sonora, Sinaloa, Chihuahua, Coahuila and Tamaulipas. The planting of transgenic maize had been prohibited for 11 years in Mexico, where maize was first domesticated. The experiments are meant to test hardier varieties of the crop, and federal officials say that they are implementing controls to prevent gene flow. Ariel Álvarez Morales, executive secretary of the Mexican Inter-Secretarial Commission on Biosafety of Genetically Modified Organisms, described the experimental planting as a compliance trial to see how the companies and the plants perform. "We want to see how the planting will work in these conditions," he says. Plots will be less than half a hectare in area, seed-planting will occur at different times from that of natural varieties, and farmers will be surveyed about the effect on native maize. In Sonora, where Monsanto has begun planting, transgenic maize is kept 500 metres away from conventional maize fields, says Eduardo Perez Pico, the firm's chief of research and regulatory affairs for the Latin American region. However, nearly 2,000 scientists have signed a petition to block the experiments. "There is no way to stop gene flow to the native crops," says signatory Montgomery Slatkin, a geneticist at the University of California, Berkeley. Greenpeace and other groups filed a legal challenge, which the government has rejected. "If Mexico experimentally plants transgenic maize, it should be done with ideal experiments and a great capacity to monitor them — but we don't have either," adds José Sarukhán Kermez, a Mexican biologist who has served in top ministerial posts and is a former rector of the Autonomous National University of Mexico (UNAM) in Mexico City. One facet of the debate surrounds the US firm being used by the Mexican government to train and equip staff at two reference labs for transgene testing in Mexico City. The firm, Genetic ID, is a spin-off by John Fagan of the Maharishi University of Management in Fairfield, Iowa, which favours organic crops and transcendental meditation. Álvarez Morales says the firm was chosen because of its widely known analytical techniques. But geneticist Elena Alvarez-Buylla, of UNAM's Institute of Ecology in Mexico City, questions whether the company's methods are sensitive enough to detect transgenes after several generations of plant growth. Earlier this year, her group reported that Genetic ID failed to detect transgenes in blinded samples1. Genetic ID responded that Alvarez-Buylla's results were due to sample contamination2, which she challenged3. ADVERTISEMENT Jay Reichman, an authority on transgenic testing with the US Environmental Protection Agency in Corvallis, Oregon, says that "overall the combined evidence suggests" that at least two transgenes "were present within the plant tissues" in question. In particular, Reichman noted that Alvarez-Buylla showed newly grown test plants believed to harbour transgenes were resistant to herbicide, indicating that they bore transgenes just like commercial seeds modified to be herbicide resistant. Fagan disputes the criticism. Still, he too is against transgenic planting, citing the potential contamination of native maize: "It is very, very unacceptable." (See also 'Maize genome sequenced'.) References 1.Piñeyro-Nelson, A. et al. Mol. Ecol. 18, 750-761 (2009). | Article | PubMed | ChemPort | 2.Schoel, B. & Fagan, J. Mol. Ecol. 18, 4143-4144 (2009). | Article | PubMed 3.Piñeyro-Nelson, A. et al. Mol. Ecol. 18, 4145-4150 (2009). | Article Comments If you find something abusive or inappropriate or which does not otherwise comply with our Terms or Community Guidelines, please select the relevant 'Report this comment' link. Comments on this thread are vetted after posting. #8951 The procedures to detect and prevent 'gene flow' should have been systematically tested, and the results peer reviewed, for each plant involved BEFORE deploying the GMOs. Too late, now — the dinosaurs are loose. Other countries in Central and South America, also centers of domestication for crops vital to human survival, will be pressured to repeat Mexico's tragic mistakes. The disputes over detection and contamination do not pass my 'Smell Test'. Nature and Science magazines have not distinguished themselves regards the possibilities that gene flow could even occur. Report this comment2009-11-28 12:14:01 PM Posted by: joe woodside#8966 I believe the whole article starts with the wrong foot. "Natural maize (corn)" does not exist. Maize is a product of human manipulation which is totally unable, as most crops, to survive in the wild without man's intervention. If they were able, agriculture would not be a difficult job. Now, coming to the issue of landraces and transgenic maize, I have the following comments: ◦The presence alone of a transgenic variety or trait does constitute any risk (for health, environment or biodiversity) per se. Major regulatory authorities and scientific societies accept Bt corn as safe for human and animal consumption on the basis of submitted evidence. Also extensive usage in many countries for around 10 years without complaint at the farm level can be added as evidence. Other insect resitant corn varieties developed by conventional breeding (see 1) are grown and used without any safety test because they are conventional. Have these been demostrated safe (for health, environment or biodiversity) in the name of some natural principle? ◦Modern hybrids have been grown in the region at least for some 3 decades now, and the landraces survived just fine. If cross pollination occurs, hybrids between commercial cultivars and landraces would be obvious (by several morphological differences in the first few generations at least) in their fields and could be either selected or not by the grower. ◦In the original sample collection in the Pineyro (Alvarez-Buylla) paper, the selected ears were confirmed to be landraces by the growers, which would be surprising if the transgenes had been recently introduced by hybridization, as one would expect. This makes the claim of the authors somewhat suspect. ◦if the transgenes are truly mixing, one expects that some of the plants are herbicide tolerant, some are insect resistant and some are both. This can be easily tested and the controversy put to rest. ◦Even if this is the case (that an as yet undemonstrated mixing is occurring), so what? Landaraces will still continue to be landraces and naive people would still believe in natural maize. if the farmers see the Bt trait as beneficial, they will introgress it into their landraces. The Bt trait has been shown to reduce fumonisin content of maize (2) and fumonisin are linked to Neural Tube defects and other severe illnesses (3). If some people reject the possibility of the Bt trait in a landrace as a heresy to natural biodiversity, then they are not only little understanding of crop biology, they also have little concern for human suffering. The old adage "I love humanity, it's people I can't stand" should be now turned to "I love a wrong idea of environment, but I still can't stand people". Best regards, P.M. references 1 Barry, D., Alfaro D., and Darrah L. L. (1994) Relation of European corn borer (Lepidoptera: Pyralidae) leaf-feeding resistance and DIMBOA content in maize. Environ. Entomol. 23:177–182. 2 Wu F. (2006) Mycotoxin reduction in Bt corn: potential economic, health, and regulatory impacts. Transgenic Res. 15:277-89. 3 Wild CP, Gong YY. (2009) Mycotoxins and human disease: a largely ignored global health issue. Carcinogenesis. Oct 29. Report this comment2009-12-02 09:44:04 AM Posted by: Piero Morandini#9098 Corss-pollination is not exclusive of transgenic maize. Modern conventional maize can also pollinate “native” maize varieties. Modern maize have been cultivated for decades next to the “native” maize and cross pollinating it. So, the named “native” maize is not really native. If the nearly 2,000 scientists (Of which speciality?) that think "there is no way to stop gene flow to the native crops" are worried about the conservation of the “native” maize varieties, then they must ask not only to stop cultivating transgenic maize, but also stop cultivating any modern imbreed line of maize in Mexico.