From gluten-free wheat to bananas immune to the feared Panama disease: CRISPR-Cas, discovered by Wageningen University & Research (WUR), makes it possible to improve crops faster, more accurately and at a lower cost. A world with sufficient healthy food is within reach.
How does it work?
Bacteria have an ingenious immune system against viruses. This was discovered by a team of Wageningen microbiologists involved in an NWO-project (Dutch Research Council) a decade ago. The unicellular organisms have so-called CRISPRs on their chromosomes: identical pieces of repetitive DNA, separated by variable pieces. In addition to these CRISPRs, there are Cas-genes that code for Cas-proteins. If a virus’ DNA penetrates the cell, the affected bacteria absorbs small samples of it in its own DNA’s CRISPRs. Copies of this CRISPR-DNA then form complexes that protect the cell. If the virus attacks the cell again, its DNA is recognised and mercilessly chopped to pieces.
A flue-shot for bacteria, an excellent application in itself. But further investigation revealed that CRISPR-Cas also allows you to cut human, animal and plant DNA in the desired places. This allows us to conduct minute mutations in a way similar to nature’s approach. Through the use of CRISPR-Cas, you can change a small, wild tomato strain into a large tomato fit for consumption within a year. This only requires DNA adjustments in 15 base pairs, while conventional methods would require the alteration of up to 15 million base pairs.
CRISPR-Cas has accelerated global scientific research on crop improvement. Plant breeders in the United States and China are already using this promising technology, but in Europe, legislation prevents the method from reaching the market. The EU-project CHIC, coordinated by Wageningen University & Research, demonstrates the added value of CRISPR-Cas and fosters the societal debate on the amendment of the current legislation. So that this ‘bacterial anti-virus system’ may contribute to a future world with enough food for all.