Scientists at Rothamsted Research have developed gene-edited wheat with substantially lower levels of asparagine, without compromising yield, offering a potential pathway to safer food production and easier compliance with food safety regulations.
Findings from two years of field trials show that wheat produced using CRISPR genome editing can significantly reduce concentrations of free asparagine, an amino acid that can be converted into acrylamide during common cooking processes such as baking, frying and toasting. Acrylamide is considered toxic and is regarded as a probable carcinogen.
The study, carried out with partners including the Karlsruhe Institute of Technology, the Leibniz Institute for Food Systems Biology, the Technical University of Munich, the University of Reading and Curtis Analytics Limited, compared CRISPR-edited wheat lines with conventionally mutagenised TILLING lines, in which random mutations are introduced using chemical treatment, according to a press release.
The CRISPR approach targeted the asparagine synthetase-2 (TaASN2) gene, which plays a central role in asparagine production. One edited line also included a partial knockout of the related TaASN1 gene. These targeted changes reduced free asparagine levels in the grain by 59%, and by as much as 93% in the dual-edited line, with no loss of yield.
By comparison, wheat developed through traditional TILLING methods achieved a 50% reduction in free asparagine, but this came with a yield penalty of almost 25%, likely because of unintended mutations elsewhere in the genome. The findings underline the greater precision and efficiency of gene editing compared with conventional breeding approaches.
“This work demonstrates the power of CRISPR technology to deliver precise, beneficial changes in crop genetics,” lead researcher Dr. Navneet Kaur, from Rothamsted Research, said. “With supportive regulatory frameworks, we can unlock significant benefits for agriculture and food systems.”
Importantly, the reduction in asparagine led directly to lower acrylamide formation in food products. Bread and biscuits produced from the edited wheat contained substantially less acrylamide, with levels in some toasted bread samples falling below the limit of detection. By contrast, current evidence suggests that conventional breeding would be unlikely to achieve a comparable outcome.
These findings come at a significant time as regulatory scrutiny of acrylamide continues to increase. Current EU legislation, Regulation (EU) 2017/2158, already sets benchmark levels for acrylamide in food, and the European Commission is expected to introduce new maximum levels this year. These measures will affect food producers across Europe as well as international trading partners, including the UK. The research also aligns with recent policy developments in England on genome-edited crops under the Genetic Technology (Precision Breeding) Act 2023.
