In a cabinet meeting of the Baden-Württemberg Government on July 21, a funding programme for sustainable agriculture with biotechnology established by Research Minister Theresia Bauer was discontinued; planned field trials were stopped. It was said that the Federal Government's concerns about risks and consequences were too significant. In response, scientists from eight Baden-Württemberg universities and the Max Planck Institute for Developmental Biology in Tübingen wrote an open letter to Minister-President Winfried Kretschmann on July 29.
Detlef Weigel, Managing Director at the MPI for Developmental Biology, is critical of the surprising decision of the Baden-Württemberg Government: "The establishment of the research programme seemed to us to be a logical consequence of a dialogue with all stakeholders, which Minister Bauer has been conducting for quite some time. By comparing this with established agricultural methods and involving different social representatives, such a project may lay the foundation for evaluating the opportunities and risks of genome editing openly and according to manifest scientific criteria.
For Weigel and his research colleagues, a central motivator is climate change: "If we want to counteract climate change, we must use all the means at our disposal. Gene scissors, such as CRISPR/Cas, allow us to achieve the same changes that nature spontaneously makes to the genome of plants in a much shorter time. With this method we can make plants more resistant to heat and drought, and such plants are no different from their naturally mutated counterparts. They also contain no foreign genes and cannot be distinguished from those from conventional breeding. The big question, however, is whether drought-resistant varieties are also competitive in yield. This can only be decided by field trials."
The public discussion about green genetic engineering has been controversial for years. Critics portray the situation as industry-oriented and not following the ecological principles of agriculture. "However, such a position does not take into account current developments. For example, colleagues have used genome editing to introduce resistances to the widespread rice brandy pathogen in different rice varieties in order to develop sustainable resistance management, based on ecological principles and in combination with digital technologies," Weigel continues.
Based on these and many other examples, an overwhelming majority of scientists in Germany, Europe and overseas are convinced that genome editing can make an important contribution to sustainable agriculture and food safety. Together with his colleagues from the universities of Baden-Württemberg, Detlef Weigel hopes to continue the dialogue with the Baden-Württemberg Government in order to contribute to the debate with scientific expertise.
More about Genome Editing
Gene scissors, molecular scalpel – these descriptive terms are intended to convey what the new method of gene editing with rather unwieldy name of CRISPR/Cas9 can do. As they suggest, the system, which, in its natural form, consists of two RNA molecules and one protein molecule, can cleave the hereditary molecule DNA. Moreover, it can do this with surgical precision at a specific site in the genome. This enables researchers to switch genes off or insert new sequences at the cutting site. As a result, DNA can be modified much faster and more easily than was possible using previous gene-editing methods. Although the system basically sounds simple, various factors must be coordinated with extreme precision for the gene scissors to be able to function with such accuracy. For this reason, even after 30 years of research, the functioning of CRISPR/Cas9 is still not entirely understood.
Natural functions of CRISPR-Cas
We humans often identify bacteria as pathogens. But bacteria can also become ill. Some viruses actually have specialized in attacking these tiny microbes. These viruses, which are known as phages, are somewhat reminiscent of space probes that dock at remote planets. They inject their DNA into the bacterial cell, which then reproduces it, thereby creating new phages - a process that can be fatal for the host cell. Like other organisms, bacteria have developed ingenious mechanisms for defending themselves against such invaders. The CRISPR-Cas systems are one such mechanism. Read more.
Functioning of CRISPR-Cas9
With the CRISPR-Cas9 system, the CRISPR- and spacer sequences are translated into the CRISPR-RNA (crRNA). Before the latter can lead the Cas9 protein to the cutting site on the DNA, it must be converted into its final form by cutting enzymes and parts must be removed from it. RNase III is such an enzyme. Together with the tracrRNA sequence it transforms the original form of the crRNA into a mature and functional molecule. Read more.
Proposal for the assessment of new methods in plant breeding
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 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. Read more.
Prof. Dr. Detlef Weigel
Phone: +49 7071 601-1410