Tests to detect products developed using new gene editing techniques could be available within a year, according to a GMO testing expert. John Fagan, CEO of Health Research Institute and a molecular biologist who pioneered an early GMO test, says that the information and technology is available to develop tests to detect crops and products derived from gene editing techniques such as CRISPR, TALEN, and ODM (oligonucleotide mutagenesis).
“Any of the leading GMO testing labs could create these tests. We expect to see PCR tests for ‘GMO 2.0s’ to be out within the next year,” Fagan says.
“If you change the DNA sequence, you can detect the change”
PCR, or polymerase chain reaction, is the standard laboratory test to detect genetically engineered DNA in crops and food products. PCR detects the foreign genes or “transgenes” inserted into the DNA of a sample. But the challenge with gene-edited traits is that no foreign DNA is introduced; changes are made to existing genes. Still, Fagan says PCR can detect those changes.
“Those who are attempting to promote the idea that GMO 2.0 crops are not GMOs make the point that these crops cannot be distinguished from natural mutations,” Fagan says. “That is not important for creating GMO tests. These are commercial products and will be patented. As such the sequences that differentiate them from natural crop varieties will be discoverable and can be used to develop tests to detect them by PCR. The basic point is that all these technologies, CRISPR, TALEN, and ODM change the DNA sequence and if you change the DNA sequence, you can detect the change with PCR.”
Jamie Welch, scientist and technology product manager at EnviroLogix, a GMO test kit manufacturer, agrees that PCR is capable of detecting gene edited traits.
“Most gene-edited traits can be detected by designing assays that target the specific edited molecular sequences. These sequences are detected by using molecular amplification techniques like PCR, which can specifically detect even single base pair differences in DNA.”
Though Welch also thinks some gene-edited traits may not be detectable. “These gene-edited crops are created using techniques that introduce the seamless integration of a native trait from one genetic background to another.”
But he says the number of undetectable gene-edited traits is expected to be very low.
Identifying gene-edited molecular sequence is key
Non-GMO certification programs such as the Non-GMO Project rely on GMO test methods to validate that products are non-GMO. Having tests for these new GMOs are essential for these programs.
Tests are now available for the Simplot Innate Potato and Arctic Apple that were developed using RNA interference (RNAi) technology to silence genes. Three laboratories, Eurofins-GeneScan, OMIC USA, and SGS can test for those RNAi products. EnviroLogix has also developed a DNAble assay to detect the RNAi trait in the Artic Apple.
According to Welch, a major challenge of developing a test for gene-edited traits will be identifying the specific gene-edited molecular sequence. GMO testing labs currently rely on receiving “reference materials” or information about genetic sequences of GMO traits from biotechnology companies so they are able to identify them with testing. Such information about gene-edited traits will also need to be available to labs in order to develop tests.
Chong Singsit, laboratory manager at OMIC USA, a GMO testing lab, says gene editing companies may not feel the need to release proprietary information about their genetic sequences because the U.S. government doesn’t currently regulate gene editing.
“Companies won’t bring samples to test unless they are required to do so. If they don’t come forward, we won’t be able to develop a test method,” he says.
But Fagan is confident that tests can be developed even without regulatory requirements. “With any commercial GMO, there will be enough information out there to allow scientists to directly, or with a little molecular biological detective work, develop a PCR test for it.”
Ultimately, Fagan says market pressure or disruption, particularly in the European Union, which may regulate gene-edited traits as GMOs, will force biotechnology companies to disclose the traits.
“Customers of these biotech companies are going to require them to disclose the sequences and provide testing methods to EU regulators.”
Singsit also thinks market forces could force companies to make information about gene-edited genetic sequences available.
“Perceptions are changing. If you want to bring a gene-edited trait to the marketplace you may have to share information about it.”