Gene-Edited Wheat Reduces Cancer-Causing Acrylamide in Toast

Researchers at Rothamsted Research in Harpenden, Hertfordshire, have developed a gene-edited wheat variety designed to significantly reduce the levels of acrylamide, a probable carcinogen, in toasted bread and biscuits.

The development utilizes CRISPR genome editing to target the gene responsible for the production of free asparagine, an amino acid used by the plant to store nitrogen. When wheat products are baked, fried, or toasted, free asparagine converts into acrylamide.

Technical Results and Crop Performance

Results from two years of field trials indicate that the CRISPR-edited wheat can maintain significantly lower concentrations of free asparagine without negatively impacting crop yields. This reduction in the precursor amino acid translates directly to lower acrylamide formation in finished food products.

In tests involving bread and biscuits made from the edited wheat, researchers observed substantially reduced acrylamide levels. Some bread samples showed concentrations that fell below detectable limits even after the toasting process.

British scientists reported that the DNA alterations reduced the level of the cancer-causing chemical by more than 90 per cent.

The researchers compared these CRISPR-edited lines against wheat treated via traditional approved methods, which involve using chemical agents to create random mutations in the genetic material.

Industry and Health Implications

Acrylamide has been identified as a serious concern for food manufacturers since its discovery in food in 2002. The compound is known to cause cancer in rodents and is classified as probably carcinogenic for humans.

While the concentration of acrylamide in raw bread is relatively low, it increases multiple times over during toasting. The chemical pathways that produce the color, flavor, and aroma of toast are similar to those that produce acrylamide, meaning darker and more flavorful toast typically contains higher levels of the compound.

Beyond wheat products, acrylamide is found in other foods that undergo high-temperature cooking, including:

• Coffee
• Chips and roast potatoes
• Crisps and other snacks

Regulatory Challenges and Market Access

Despite the technical success of the gene-edited wheat, the product faces significant regulatory hurdles in international markets. Reports indicate that the European Union has banned the “super-wheat” designed to cut the cancer risk associated with toast.

In the United Kingdom, the project has involved collaboration between Rothamsted Research and the University of Bristol. Professor Nigel Halford, the project leader, stated that researchers were preparing an application to the UK Government to conduct a field trial of the new wheat starting in the autumn.

This initiative was positioned as the first trial of genome-edited wheat to be carried out anywhere in Europe. Sarah Raffan, a researcher who completed a PhD project on the low asparagine wheat, was designated as the lead researcher for the field trial.