Determination of percentage of RoundUp Ready® soya in soya flour using real-time polymerase chain reaction: Interlaboratory study

• Published in: Journal of AOAC International Vol. 86; no. 1; pp. 66 - 71
• Main Authors: HIRD, Heather, POWELL, Joanne, GARRETT, S, HARRIS, N, LAKE, R, MOEBES, A, MORENO, C, POPPING, B, RENTSCH, J, SANG, K, TAESAN, K, WISEMAN, G, JOHNSON, Mari-Louise, OEHLSCHLAGER, Sarah, ANKLAM, E, BUCHNO, M, BULKMANS, C, VAN DUIJN, G, FOTH, M, GACHET, E
• Format: Journal Article
• Language: English
• Published: Gaithersburg, MD AOAC International 2003
• Subjects: Biological and medical sciences; DNA, Plant - analysis; Flour - analysis; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; General aspects; Glycine max - genetics; Methods of analysis, processing and quality control, regulation, standards; Plants, Genetically Modified - genetics; Polymerase Chain Reaction; Sensitivity and Specificity; Polymerase chain reaction; Grain legume; Accuracy; Analysis method; Quality control; Transgenic plant; Recombinant DNA; Soybean; Molecular biology; Genetically modified organism; Real time; Soybean meal
• ISSN: 1060-3271; 1944-7922
• DOI: 10.1093/jaoac/86.1.66

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%.