What is the difference between "gene editing" and "transgenic" breeding techniques?
Release date: 2016-07-26
Aiming at the difference between the gene editing technology and the existing genetically modified breeding technology, recently, at the transgenic science salon co-sponsored by the Agricultural Biotechnology Science Communication Platform, Zhu Yan, a researcher at the Institute of Genetics of the Chinese Academy of Sciences, responded to a question from the First Financial Journalist. The technical system is the same. But transgenics do "addition," and gene editing can do both "subtraction" and "addition." In some cases, these two technologies can serve the same purpose.
For example, phytic acid is a component in plant seeds that animals cannot easily digest after eating. Then the "addition" is used to degrade phytic acid and then absorbed by water, and the "subtraction" is used to eliminate the phytic acid synthesis gene so that it can no longer synthesize phytic acid. The expected effect of both is the same.
Jiang Tao, a senior engineer of the Institute of Genetics of the Chinese Academy of Sciences, said in an interview with First Financial News that genome editing technology is to adjust-modify (delete or add) specific DNA sequences of the genome, and can be accurate to a specific character of the genome. -Base pairs.
He further explained that the "deletion" can be called "subtraction", which is based on the design of scientists to remove existing parts, such as the genes that produce anti-nutritive effects and cause human allergies after eating. "Addition" can be visually called "addition", which is to add genes that the crop did not originally have, so that scientists hope that the crop can obtain new traits, such as a crop disease resistance gene. Moreover, the gene insertion position can be specified in advance.
As for transgenic technology, Jiang Tao explained that unlike the aforementioned gene editing technology, scientists fully understand the target gene, but the genome of the recipient crop is not necessarily clear, so the location of the genome of the recipient plant cell is uncertain in advance.
Regarding these two technologies, previously, Fu Jierui, the global vice president of DuPont Pioneer, once accepted an interview with "China Business Daily". "Each technology solves specific problems." Just one of them.
Fu Jerui said that the challenge for breeders in the field of traditional waxy corn products is that the yield of traditional waxy corn varieties is low. Using CRISPR-Cas gene editing technology, breeders can directly introduce naturally occurring waxy corn traits into the best hybrid varieties, develop new products very similar to traditional corn, and solve the problem of low yield of waxy corn. This technology also allows crop breeders to work more efficiently and accurately.
He said that traditional methods of traditional crop breeding required years of backcrossing and selection, but now the same results can be achieved through a new breeding technology of gene editing. And there is no foreign DNA in the final product developed with this tool, so no foreign protein will be generated, and the breeding efficiency is greatly improved.
Obviously, this is not the same concept as the need for transgenic technology to introduce foreign DNA. The US Department of Agriculture also believes that this type of next-generation product developed through CRISPR-Cas breeding technology does not fall into the category of "should be regulated by the USDA Biotechnology Regulatory Service."
According to media reports, hybrid waxy corn will be the world's first commercial agricultural product developed by DuPont Pioneer through the application of CRISPR-Cas advanced breeding technology. This new generation of fine hybrid glutinous corn is expected to be available to US growers within five years and is still pending field trials and regulatory review. As for the time to market, Fu Jerui said, “This is not a requirement from the regulatory level, but it is related to the product development cycle.” He said that before we launch a new hybrid, we must evaluate the hybrid for 4-5 years. Gene editing technology follows the same development cycle.