German Federal Agency for Nature Conservation (BfN)


CRISPR-Cas und Genome Editing

The function of CRISPR/Cas

The discovery of CRISPR/Cas represents a technical breakthrough in genetic engineering. CRISPR/Cas is a molecular complex that plays a role in the immune response of bacteria against viruses, which can also be used in biotechnology. The combination of a synthetic CRISPR component, with which gene sequences can be controlled specifically, and the nuclease Cas, with which these gene sequences are then cut, enables genetic information to be changed at predetermined locations. The use of CRISPR/Cas and other genome editing methods increases the range of possible modifications.

Areas of application

In the evaluation of genome editing, three application areas can be distinguished:

The term "conventional" genetic engeneering is used if individual genes are modified or newly introduced in an organism. The new techniques play a role in this respect, both by facilitating the simplification of methods and by offering new application possibilities. These quantitative and qualitative differences will lead to new regulatory challenges, particularly in terms of risk assessment and monitoring. Furthermore, CRISPR/Cas no longer requires the use of marker genes, which can have an additional impact on risk assessment, monitoring and traceability procedures.

However, CRISPR/Cas is also used in the complex alteration of the genetic material, the so-called Synthetic Biology. This may involve the introduction of many new genes, such as entire synthesis pathways into an organism at a predefined point in the genome. Or the introduction of synthetic genes that are not found in nature. Gene Drives are also mentioned here, in which CRISPR/Cas is also inherited, which means that the Mendelian inheritance rules can be overridden and genetic engineering changes in wild populations can spread more widely. Gene drives can be used, for example, to decimate wild populations by introducing genetically determined sterility or to introduce new genes into them. Synthetic gene drives are therefore genetically engineered modifications that are carried out in nature on wild organisms. There are already concrete considerations to release gene drives not only in the largely well known agroecosystems, but also in a multitude of wildlife habitats. In general, the use of synthetic biology for risk assessment and monitoring is a challenge because it creates completely new organisms and classical approaches to risk assessment and monitoring may no longer be applicable.

The third area is currently the subject of intense debate, partly because the legal classification as genetic engineering is being called into question. With the so-called new techniques, individual base pairs - the "letters" of DNA - can be selectively added or removed in genes by means of methods such as CRISPR/Cas. Genes can either be silenced, altered or amplified in their effect. Small changes have the potential to make a huge impact, precisely because they are now targeted.


Are plants created with the help of new genome editing methods such as CRISPR/Cas to be regarded as genetically modified organisms? Are they covered by European genetic engineering law? The European Court of Justice ruled on these questions on 25th of july 2018: Organisms obtained by new genetic engineering are in principle subject to the European genetic engineering law.

Judgment of the European Court of Justice about the scope of application of the genetic engeneering law

A legal opinion (Spranger, T.M. 2017) commissioned by the Federal Agency for Nature Conservation (BfN) showed in 2017 that the various specialized European laws outside of genetic engineering law do not provide adequate control and testing standards for the so-called new technologies. 

Press release regarding the legal opinion of Spranger, T.M. (2017)



Legal opinion on the analysis of various European directives and regulations with regard to their potential to regulate environmental effects of New Technologies besides Genetic Engineering Law:

Spranger, T.M. 2017 (engl) and summary 

Press release 15.11.2017


Last Change: 23/01/2019