CRISPR/Cas9 is a new method for targeted genetic changes. Together with other methods, it is part of the so-called genome editing toolbox. At the moment, genome-editing is mostly discussed in the context of medical applications, but its use is perhaps even more promising for plant breeding. Scientists from China, the United States and Germany, among them Prof. Dr. Detlef Weigel of the Max-Planck-Institute for Developmental Biology in Tübingen, have now proposed a regulatory framework for genome editing in plants that has been published in the journal Nature Genetics.
Using genome editing, DNA can be altered in a very precise manner. Often, only a single base, that is one letter of the genome, is replaced or deleted. This is essentially the same as the constantly occurring genome changes in nature due to random mutations. After such a mutation or genome-editing have taken place, their consequences are indistinguishable. This is not due to technical shortcomings, but to the factual lack of physical, chemical or biological differences.
“We thus do not see a reason for considering genome edited plants as genetically modified organisms”, says Weigel. The changes resulting from genome-editing should however be analysed and documented to ensure that no remnants of foreign DNA, if such an approach was used for genome editing, are left behind. Apart from that, plants changed in this way should not be subject to stricter rules than conventionally bred plants.
The aim of plant breeding is to continually improve advantageous traits in order to make our crops more resistant against fungal infection, to help them cope better with drought or to thrive with less fertilizer. One way to reach this goal is to cross cultivars with different advantageous traits.
As an alternative, chemicals or radiation are deployed, both of which cause randomly distributed mutations throughout the genome. Unfortunately, for both techniques a large portion of the resulting offspring is not better or even worse than the parental plants, and finding promising individuals is often lengthy and tedious. Both techniques are among the standard tools of conventional breeding, whose products can enter the market without authorization.
For several decades, it has been possible to insert genes into plants, using genome engineering methods. These could be genes coming from other plants, or from completely different organisms such as bacteria. A disadvantage of these techniques is that it cannot be controlled where exactly in the genome the new genes get inserted. Thus many candidates have to be scrutinized until a plant with the desired traits is found.
In reports of genome editing, metaphors such as genome surgery or genetic scalpel are often used. “Conventional genetic engineering can be compared to open-chest surgery” illustrates Weigel, while genome-editing would correspond to minimally invasive surgery, because one can precisely determine where in the genome a change is supposed to happen. Using genome engineering methods one can also precisely replace genes of one species with genes of other varieties or close relatives – which is one goal of conventional breeding as well. Genome-editing allows to achieve the same alterations as conventional breeding, but much faster.
For these reasons, the scientists advocate the following common sense approach concerning the development and authorization of genome-edited plants: First, the risk of uncontrolled spread should be minimized during the development phase. Second, the resulting DNA-changes should be precisely documented.
Third, it has to be taken into account that CRISPR/Cas9 techniques may in the beginning require insertion of foreign DNA into the cell; if this is the case, it has to be documented that the foreign DNA has been completely removed. Finally, has a gene been replaced by one from a different species, it should be stated how close the two species are related to each other.
Are they only distantly related, additional case-by-case considerations might be necessary. For registration of new varieties, documentation regarding these points should be included, but otherwise, genome edited plants should be treated like conventionally bred varieties.
The European Union has not finalized their assessment, but in both Germany and Sweden the responsible authorities have already declared, that certain genome-edited varieties are in principle the same as products of conventional breeding. “An important aim of breeding is to make agriculture more sustainable. Genome editing can, for example, help when breeding for resistance to fungal infection without the use of chemical pesticides. We should not miss out on such opportunities,” states Weigel.
A proposed regulatory framework for genome-edited crops. Nature Genetics.
Prof. Dr. Detlef Weigel
Phone.: 07071 601-1410
Nadja Winter (PR Officer)
Phone: +49 7071 601- 444
The Max Planck Institute for Developmental Biology conducts basic research in the fields of biochemistry, genetics and evolutionary biology. It employs about 350 people and is one of four Max Planck Institutes located at the Max Planck Campus in Tübingen. The Max Planck Institute for Developmental Biology conducts basic research in the areas of biochemistry, molecular biology, genetics, cell- and evolutionary biology. It does not develop genetically modified crops. It is one of 83 research institutes that the Max Planck Society for the Advancement of Science maintains in Germany.
Nadja Winter | Max-Planck-Institut für Entwicklungsbiologie
At last, butterflies get a bigger, better evolutionary tree
16.02.2018 | Florida Museum of Natural History
New treatment strategies for chronic kidney disease from the animal kingdom
16.02.2018 | Veterinärmedizinische Universität Wien
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).
Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
16.02.2018 | Information Technology
16.02.2018 | Health and Medicine
16.02.2018 | Physics and Astronomy