Kawall K (2021) → Genome-edited Camelina sativa with a unique fatty acid content and its potential impact on ecosystems. Environmental Sciences Europe 33 (1):38. doi:10.1186/s12302-021-00482-2
The study provides an overview of unwanted and unexpected effects that a release of genome-edited plants can have on ecosystems. These result from the intended traits introduced by genome editing processes, such as CRISPR/Cas gene scissors, that can influence various metabolic processes. CRISPR/Cas has greatly increased the possibilities and the speed with which the genome of plants can be changed, regardless of whether additional genes are integrated into the genome. Even small genetic changes that may be induced several times and in combination with so-called SDN-1 applications, can significantly change metabolic pathways and ingredients.
The study focusses on a specific plant, Camelina sativa, which is naturally rich in polyunsaturated fatty acids. In previously published scientific papers analyzed in this article, the gene scissors were used to increase the level of oleic acid in the seeds and to reduce the level of easily oxidizable fatty acids. This is intended to extend the shelf-life of the extracted camelina oil. Camelina has a six-fold set of chromosomes, and thus six copies of a gene in its genome. Gene scissors were already used to simultaneously knock out up to 18 copies of three genes in the genome of the camelina in order to produce plants with a higher oleic acid content. Until now, such interventions were hardly or not at all possible using conventional methods and can lead to the occurrence of completely new biological properties.
In addition to the intended properties, there can be unwanted effects on various biochemical processes. For example, the formation of certain messenger substances with which plants communicate and, e.g. ‘warn’ of a pest infestation, may be disrupted. If the content of certain fatty acids is reduced by CRISPR/Cas gene scissor applications, this can lead to fewer messenger substances being formed, as the formation depends on the availability of these fatty acids. This can make the genome-edited plants more susceptible to certain pests. In addition, changes in the composition of fatty acids can also affect existing food webs. For example, a genome-edited plant, with changes in the composition of its fatty acids that serves as a food source for a specific insect, can impair the development of that insect. This insect is then no longer or only partially available as a food source for other animals, which can lead to disruption in the food web. There is also the possibility that the genome-edited plants will cross with wild species and cause unintended effects in subsequent generations. Additionally, the genome-edited camelina could also persist in the environment and spread uncontrollably.
Even apparently small changes in the genome of plants induced by the gene scissors CRISPR/Cas can therefore have major effects on ecosystems. For this reason, plants with new traits must be thoroughly checked for risks even if no additional genes are inserted.