CRISPR poplar

The flowering dreams of genetic engineering

China, the US and Sweden are among those countries where new genetic engineering (New GE) is used to manipulate trees. The first applications for releases of New GE poplars were already filed in Sweden in 2016. These trees were genetically altered in a number of ways affecting, for instance, flowering, growth, production of branches, leaves and roots. The economic interests behind these projects includes faster growth and changes in the quality of the wood for the paper industry.

In 2022, there was a genetic engineering breakthrough in the US: poplar trees normally only flower after seven to ten years, but after a gene scissors-based intervention they flowered after just four months. Therefore, even without the insertion of additional genes, these plants show characteristics that do not occur naturally in the species.

The aim of the intervention: similar to arable plants, the early flowering genetically engineered poplars could be propagated, crossed and selected. This is supposed to considerably accelerate the market introduction of genetically engineered poplars with all kind of traits. At the same time, these poplars may have an increased potential to spread if fertile pollen and seeds are produced much earlier than would be expected naturally.

Forest trees have complex interactions with their environment, including soil organisms, insects and wild life species. Within the lifetime of a poplar tree, it can produce billions of seeds and pollen, which can be transported by wind over many kilometers. The genetically engineered DNA can spread via pollen, seeds, shoots and cuttings. The introgression of genetically engineered trees into native populations may have irreversible disruptive consequences for the ecosystems.

This example shows: New GE can change the characteristics of a species in ways that go far beyond what occurs naturally, or what can be expected from conventional breeding. No additional genes need to be inserted to achieve these extreme plant characteristics. From the perspective of the precautionary principle, the release of genetically engineered plants must not be permitted if it can result in their uncontrollable spread in the environment.

 

 

 

Publication year: 
2024