Eppendorf Array Technologies next month will launch an upgraded version of its DualChip GMO Microarray Kit that will enable users to test food, feed, and seed products for 12 different European Union-authorized and unauthorized genetically modified organisms in parallel on Eppendorf’s Silverquant array detection platform.
According to Barbara Schaffrath, a product line manager at the Namur, Belgium-based firm, the upgrade coincides with the EU’s authorization of new GMOs as well as updates in EU-wide testing regulations. It is also being made at a time when the number of GMOs is increasing as more foods are produced in Asia.
The chip is targeted towards government or private-testing laboratories that screen food-related products for GMOs. Although originally positioned for use in the European market, Schaffrath said that Eppendorf has recently seen a rise in demand from Asian customers. This rise is due partially to a large amount of soy, soy-derived, and rice products that the region exports, and also because several Asian countries, such as India, have started to mandate GMO testing, she said.
“With more and more new GMOs pushing into the market, and [with] expanded import and export from China and India, other transgenic elements are being used, so the trend goes towards having a broader screening tool,” she said.
Whereas until recently most laboratories screened on PCR-based technologies using one or two target sequences, the testing market needs a first, broad-screening technology that is followed by a quantitative evaluation technology, like qPCR, she said.
The first DualChip GMO product tested for the presence of the markers p35S, Tnos, CaMV, Pnos-nptII, three gene varieties of cry1Ab-1, 1Ab-3/cry1Ac, two gene varieties of EPSPS, as well as plant markers for maize, soybean, and rapeseed.
The second version of the GMO kit will test for the markers p35S, tNos, pat, three gene varieties of cry1Ab, cry3Bb1, three gene varieties of EPSPS, bar, pNos-nptII, as well as plant-species markers for maize, soybean, rapeseed, cotton, rice, potato, and sugar beet. According to Schaffrath, the new chip will also include GMO event-specific markers for GA21, Bt176 maize, MON810, Bt11, MON863, MON603, GS40-3-2, T45, GT73, MON15985, MON531, and MON1445.
“Whereas until recently most laboratories screened mainly using PCR-based technologies using one or two target sequences, we now experience a need for a first, broad-screening step that is followed-up by a quantitative evaluation step.”
“This is the second update, and what we experienced is that, yes, there is interest from the market, but there were species missing on the [first] array, like rice, potato, and cotton,” Schaffrath said. “Then we got into the idea of not only providing a screening approach but also to include [GMO-related] event-specific sequences on the arrays to be as broad as possible.”
Schaffrath said that by analyzing the GMO markers in an array format, users could hypothetically detect the presence of EU-defined GMOs in food products, as well as the presence of unknown GMOs based on their similar genetic structure.
Eppendorf’s assays, including the GMO chip, are designed to be used with its Silverquant Microarray Detection and Scanning System, which is based on its Silverquant labeling technique that uses silver particles, rather than fluorescence, to label an experiment.
Two individual arrays are spotted per slide, and 16 individual tests, including reagents for amplification and hybridization, as well as the necessary analysis software, are provided with the GMO kit, Schaffrath said. Pricing for the kits is estimated at around €1,000 ($1,575).
In terms of competition for the test, Eppendorf appears to be one of a handful of array firms selling to GMO-testing labs in Europe. Germany’s Eurofins GeneScan has also offered GMO testing service in the past, as has Belgium’s DNAVision.
According to Schaffrath, the company’s main competitor, though, is quantitative PCR technology. Schaffrath said that Eppendorf considers qPCR to be “the gold standard in food and feed analysis” and has instead tried to position its higher-throughput technology as complementary. Hypothetically, testing labs can screen samples using the DualChip GMO kit and then confirm those results by qPCR, she said.
“You need to go back at one point and do a quantitative analysis because of the thresholds,” Schaffrath explained. “With the increasing number of GMOs, in the end our technology saves money and time by doing a qualitative screening step first and then a quantitative step for those targets you identified in the first step,” she added.
Schaffrath also pointed out that the technology was validated last year in a ring-trial study in collaboration with the EU’s Joint Research Centre. Twelve laboratories from eight different countries participated in the study, in which Eppendorf’s arrays fulfilled the 95-percent-accuracy rate required for validation requirements.
“Since those are the guys who recommend testing analysis technologies and methods, and we have a good relationship with them, you can get a good indication of what is going on in the testing community,” Schaffrath said. She added that there “definitely will be more updates” of the GMO kit because of changing EU regulations. “As soon as a new GMO is authorized, we will come up with an update,” she said.