ARS | Publication request: NMR-Metabolic Methodology in the Study of GM Foods

Submitted to: Nutrients
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 8, 2010
Publication Date: January 13, 2010
Citation: Sobolev, A.P., Capitani, D., Giannino, D., Nicolodi, C., Testone, G., Santoro, F., Frugis, G., Iannelli, M.A., Mattoo, A.K., Brosio, E., Gianferri, R., Amico, I.D., Mannina, L. 2010. NMR-Metabolic Methodology in the Study of GM Foods. Nutrients. 2:1-15.

Interpretive Summary: The development of genetic engineering technology for crop improvement has generated considerable interest among growers and consumers. However, the application of this technology and/or acceptance of genetically modified (GM) foods world-wide are hampered by continued debate on the safety of such produce. Risk assessment studies have focused on determining the substantial equivalence of GM food and traditionally-bred wild type crops. In these studies, optimized unambiguous methodologies are applied to search for differences between GM and non-GM foods. Previously, we used nuclear magnetic resonance (NMR) spectroscopy to show that engineered tomato fruit lines and their parent, non-engineered line were qualitatively equivalent for over 30 metabolites. In the present study, a team of researchers from USDA-ARS, CNR-Rome-Italy, University of Rome – Italy and University of Molise – Italy have analyzed GM lettuce plants expressing a heterologous plant homeobox gene driven by a heterologous plant promoter and compared them to the non-GM control. Twenty-two water-soluble metabolites were identified by NMR spectroscopy and quantified at two developmental stages. The NMR spectra did not reveal any novel or unusual compound in the GM lettuce, suggesting that the GM line and the wild type are basically equivalent. These data are important for agricultural biotechnologists, regulatory agencies, food consumers, growers and horticulturists.

Technical Abstract: The 1H NMR methodology used in the study of genetically modified (GM) foodstuff is discussed. The study of transgenic lettuce (Lactuca sativa cv "Luxor") over-expressing the KNAT1 gene from Arabidopsis is presented as a novel study-case. The 1H NMR metabolic profiling was carried out. Twenty-two water-soluble metabolites (amino acids, organic acids, sugars) extracted from leaves of conventional and GM lettuce were monitored and quantified at two developmental stages. 1H NMR spectra did not reveal the occurrence of any novel or unusual compound, suggesting that both transgenic and wild genotypes were equivalent. Statistical analyses on metabolite variation evidenced both the effect of natural leaf development and the contribution of the transgene, which mainly consisted in sugar metabolism alteration.