New GE salmon: Let’s talk about the risks!

Will salmon with artificially-induced genetic defects be released in Norway?

21 November 2023 / An application for the experimental release of salmon obtained from new genetic engineering (New GE, also new genomic techniques, NGT) was submitted in Norway in April 2023. This is the very first application in Europe. Now, a risk assessment of the genetically engineered salmon undertaken by Norwegian scientists came to a negative conclusion. CRISPR/Cas was used in the salmon to switch off the genes responsible for the development of the reproductive organs. The intention was to use the sterile salmon for fattening in aquaculture. A patent application has already been filed (WO2021198424). The fish would be released into enclosures in the sea which are surrounded by nets.

The genetically engineered fish would supposedly be advantageous to fish farming. One particular aim was to reduce the risk of the salmon spreading in the environment because of its sterility. In addition, the New GE salmon could possibly be fattened for a longer period of time than conventionally-produced fish, thus allowing them to reach a higher final weight. Conventionally-bred fish are only reared until they reach sexual maturity.

However, the Norwegian Scientific Committee for Food and Environment (VKM) came to a negative conclusion, as it found there were too many uncertainties in the evaluation of environmental risks. The VKM said that it had not been demonstrated that all the genetically engineered fish were actually sterile. This is due to a lack of precision in New GE techniques, which resulted in a considerable number of genetic differences between the CRISPR salmon in regard to their altered genes. This could lead to confusion when selecting animals for fattening, as only some of the fish derived from the CRISPR salmon had the desired characteristics.

According to VKM, it is also unclear how the CRISPR salmon would behave in the environment: for example, they could become competitors of younger fish in natural populations living in rivers around the fish farms. If they were not completely sterile, they could, in addition, pass on the artificial genetic defects, and thus weaken the natural populations. According to VKM, there is also a risk that the CRISPR salmon would be more susceptible to diseases and contribute to the spread of dangerous pathogens in the affected regions.

The negative VKM opinion makes it doubtful whether the fish will actually be released in 2024. The applicants, however, also make reference to a second report by another expert commission, which considers the planned releases to be less risky.

The genetically engineered salmon under discussion are also interesting against the backdrop of the planned deregulation of new genetic engineering in the EU: if the EU Commission succeeds with its plans to deregulate New GE plants, similar initiatives for animals could soon follow. This means that in the EU - unlike in current Norwegian legislation – mandatory risk assessment may also no longer be required for New GE animals in future.

Christoph Then,, Tel + 49 151 54638040