correspondence

Making the most of GM potatoes

To the Editor: crops, particularly in the European market, The recent approval of the Amflora where outcrossing or admixture of GM by the (EU)—the EU’s first crops with conventional varieties remains registration of a genetically modified (GM) such a hot-button issue. Such crops would potato in 12 years—has garnered considerable represent low-risk GM varieties, which media attention and public controversy. possibly could be cleared through approval Amflora (EH92-527-1) is a GM potato authorities in a more timely manner9. produced by BASF (Ludwigshafen, ) For example, GM potatoes resistant to that lacks amylose and instead contains potato late blight10 that are currently being (>98%) as the predominant generated (http://www.gmo-safety.eu/en/ starch1,2. Amylose ordinarily has to be removed potato/plant_diseases/462.docu.html) ©AFP to allow the industrial use of potato . would probably be more palatable to both Thus, Amflora is a highly suitable source for You say potato, I say Amflora. BASF recently the public and regulatory authorities if technical applications, such as paper, adhesive received approval from the EU to market its GM selection markers were removed and sexual and textile production. Supporters of the potato engineered with reduced amylase content reproduction were irreversibly blocked. via an antisense construct targeting granule- technology welcome the approval, which has Who knows: as late-blight disease caused bound starch synthase. taken 13 years, and consider it a regulatory by the pathogen Phytophthora infestans is a milestone, at least for GM potatoes. Opponents serious problem in the farming of organic are afraid that it heralds the opening of the Amflora were to inadvertently end up in the potatoes11, sterile GM potatoes resistant to regulatory floodgates for more transgenic human food chain through admixture with the phytopathogen might become accepted varieties. Accepting the view that the use of GM potatoes grown for human consumption, the even in the organic farming community12. technology should be based on careful case- potential health risk would be diminished, by-case consideration3, I see two key issues that as removal of the antibiotic marker would COMPETING FINANCIAL INTERESTS The author declares no competing financial interests. may not be trivial and should be discussed, as leave only the , an antisense they generate most of the public concern. construct, which lowers the expression of an Gerhart U Ryffel Amflora contains a gene encoding endogenous GBSS gene but has no protein-

© 2010 Nature America, Inc. All rights reserved. All rights Inc. America, Nature © 2010 neomycin phosphotransferase II (NptII) that coding potential on its own. Institut für Zellbiologie (Tumorforschung), Universitätsklinikum Essen, Universität confers kanamycin resistance, and critics A second concern of opponents of Duisburg-Essen, Germany. argue that this antibiotic resistance gene Amflora potatoes relates to the possibility of e-mail: [email protected] could escape via the food chain or horizontal transgene dissemination to other potatoes. transfer into ecosystems. The antibiotic Such spreading of the transgene is unlikely, 1. EFSA. The EFSA Journal 323, 1–20 (2006). marker is there as a selection gene and was as potato transgene movement by pollen 2. EFSA. The EFSA Journal 324, 1–20 (2006). 7 3. Arntzen, C.J., Coghlan, A., Johnson, B., Peacock, needed to introduce the antisense construct is very limited and escaped wild-type J. & Rodemeyer, M. Nat. Rev. Genet. 4, 839–843 that blocks amylose production by targeting potatoes have rarely been observed in (2003). granule-bound starch synthase (GBSS). Europe8. Nevertheless, these arguments 4. Lemaux, P.G. Annu. Rev. Plant Biol. 59, 771–812 (2008). Although horizontal transfer of transgenic again cannot be dismissed completely, as in 5. Lemaux, P.G. Annu. Rev. Plant Biol. 60, 511–559 traits into ecosystems is not well accepted our global world, dissemination in the long (2009). by the scientific community, the possibility term cannot be excluded and may even be 6. Cuellar, W. et al. Plant Mol. Biol. 62, 71–82 (2006). 7. McPartlan, H.C. & Dale, P.J. Transgenic Res. 3, 216– that it could happen cannot completely be likely. As commercial potato production, 225 (1994). excluded4,5. One way around this possibility especially that using GM varieties, does 8. Lauber, K. & Wagner, G. Flora des Kantons Bern: 1836 Farbfotos der wildwachsenden would be simply to remove the selection gene not require sexual reproduction, it seems Blüten- und Farnpflanzen; Artbeschreibung und 6 NptII (e.g., using the Cre/loxP system ) in reasonable to carry out gene manipulation in Bestimmungsschlüssel (Paul Haupt, Berne, future generations. This would represent an potato varieties in which the genes for sexual Switzerland, 1991). 9. Rommens, C.M. J. Agric. Food Chem. 55, 4281–4288 additional burden for the breeders of GM reproduction have been permanently deleted. (2007). potatoes, but it would also facilitate a second Such a strategy would probably negate 10. Song, J. et al. Proc. Natl. Acad. Sci. USA 100, 9128– round of transformation, if needed. Most concerns relating to the spread of potato 9133 (2003). 11. Dupuis, B., Rolot, J.L., Stilmant, D., Labbe, V. & importantly of all (scientific concerns aside), into the ecosystem. Laguesse, L. Commun. Agric. Appl. Biol. Sci. 72, an Amflora derivative lacking kanamycin In conclusion, with the addition of these 353–359 (2007). 12. Ronald, P.C. & Adamchak, R.W. Tomorrow’s Table: resistance would have much improved public two safety features, GM potatoes could Organic Farming, and the Future of Food acceptance. In fact, if in subsequent years become the standard for other transgenic (Oxford Univ. Press, New York, 2008).

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