ABSTRACT
A high throughput proton nuclear magnetic resonance spectroscopy method for the metabolite fingerprinting of plants was applied to genetically modified peas (Pisum sativum) to determine whether biochemical changes, so called 'unintended effects', beyond those intended by incorporation of a transgene, were detectable. Multivariate analysis of 1H NMR (nuclear magnetic resonance) spectra obtained from uniformly grown glasshouse plants revealed differences between the transgenic and control group that exceeded the natural variation of the plants. When a larger data set of six related transgenic lines was analysed, including a null segregant in addition to the wild-type control, multivariate analysis showed that the distribution of metabolites in the transgenics was different from that of the null segregant. However, the profile obtained from the wild-type material was diverse in comparison with both the transgenics and the null segregant, suggesting that the primary cause of the observed differences was that the transformation process selects for a subset of individuals able to undergo the transformation and selection procedures, and that their descendants have a restricted variation in metabolite profile, rather than that the presence of the transgene itself generates these differences.
ABSTRACT
An interlaboratory study was conducted to evaluate a method for determination of the percentage of RoundUp Ready (RR) soya in soya flour using Taqman technology. The method included DNA extraction from the test portion with cetyltrimethylammonium bromide buffer followed by chloroform extraction and Wizard resin cleanup steps. The DNA was then assayed with primer and probe sets specific for lectin as the endogenous control and the RR insert as the target. The percentage of RR soya in the soya fraction of the sample was calculated by using a matrix-matched standard curve. Ten samples of split-level blind duplicates were sent to 22 laboratories in 12 countries worldwide. Test portions contained 0, 0.5, 0.7,1.6, 2, and 3.9% (w/w) RR soya prepared gravimetrically from commercially available RR standard reference materials. Based on the results for test materials, the relative standard deviation for repeatability (RSDr) for the method ranged from 9.3 to 19.3% and, for reproducibility (RSDR), ranged from 20.3 to 33.7%.
