IUPAC Collaborative Trial Study of a Method To Detect Genetically Modified Soy Beans and Maize in Dried Powder

Abstract

This paper presents results of a collaborative trial study (IUPAC project No. 650/93/97) involving 29 laboratories in 13 countries applying a method for detecting genetically modified organisms (GMOs) in food. The method is based on using the polymerase chain reaction to determine the 35S promoter and the NOS terminator for detection of GMOs. Reference materials were produced that were derived from genetically modified soy beans and maize. Correct identification of samples containing 2% GMOs is achievable for both soy beans and maize. For samples containing 0.5% genetically modified soy beans, analysis of the 35S promoter resulted also in a 100% correct classification. However, 3 false-negative results (out of 105 samples analyzed) were reported for analysis of the NOS terminator, which is due to the lower sensitivity of this method. Because of the bigger genomic DNA of maize, the probability of encountering false-negative results for samples containing 0.5% GMOs is greater for maize than for soy beans. For blank samples (0% GMO), only 2 false-positive results for soy beans and one for maize were reported. These results appeared as very weak signals and were most probably due to contamination of laboratory equipment.

Phenotypic and phylogenetic segregation of Alternaria infectoria from small-spored Alternaria species isolated from wheat in Germany and Russia

“…Cultures were centrifuged at room temperature and 12 000 g for 5 min. Approximately 200 mg of the pellet was used for DNA extraction which was performed as described by Lipp et al (1999) with some modifications. Mechanical lysis was performed by grinding with a FastPrep â -24instrument (MP Biomedicals, Eschwege, Germany) for 40 s at 6Á0 m s À1 using lysing matrix A with an additional ceramic sphere.…”

“…Mechanical lysis was performed by grinding with a FastPrep â -24instrument (MP Biomedicals, Eschwege, Germany) for 40 s at 6Á0 m s À1 using lysing matrix A with an additional ceramic sphere. For DNA extraction, a CTAB protocol was used (Lipp et al 1999).…”

Quantification of Roundup Ready™ soybean in Brazilian soy‐derived foods by real‐time PCR

“…The DNA was extracted from a starting amount of 100 mg and purified from all the samples and certified reference material using a cetyltrimethylammonium bromide (CTAB) method (Lipp et al, 1999). DNA concentrations were estimated by OD at 260 nm with a spectrophotometer (Hitachi U 2010).…”

Experimental assessment of gene flow between transgenic squash and a wild relative in the center of origin of cucurbits

“…All plants in our study (parentals, F 1 , F 2 , and backcrosses) were screened for the presence of the VRT using the expression of NPTII and the promoter 35S of the cauliflower mosaic virus (P-35S CaMV) as indicators of VRT presence and functionality (Tricoll et al 1995, Lipp et al 1999; see molecular analyses in Appendix B).…”