Gene editing leads to faster production of food-friendly cassava

Originally from South America, cassava root can be used to make bread, flour, and tapioca. Keystone

Zurich researchers have used gene-editing technology to develop a variant of the starchy tuber cassava that is much easier to process for the food and paper industries.

Until now, complex and energy-intensive industrial processes have been required to turn the starchy root vegetable cassava, also known as manioc, into food and paper products. Cassava is very hardy and tolerates drought better than other starchy vegetables like corn and potatoes, making it a staple food source in many tropical and sub-tropical countries. It is one of the top five most important sources of carbohydrate globally.

Now, an international team of researchers led by the lab of Simon BullExternal link at the Swiss Federal Institute of Technology (ETH Zurich) has found a way to produce a variant of the cassava plant that lacks the molecule amylose, which is found in the root starch and makes processing the plant for food very difficult. Using the gene-editing technology Crispr/Cas9,External link the researchers removed two genes responsible for amylose production, resulting in a cassava variant that is much easier to process commercially.

 + Read about Switzerland’s policy on genetically modified organisms

In addition, the researchers integrated a gene from the small flowering plant Arabidopsis, usually considered to be a weed, which stimulated the cassava plants to flower more often. Normally, unmodified cassava plants rarely flower under greenhouse conditions, making classical breeding a very slow process. More frequent flowering made it easier to breed the new, amylose-free variety much faster, and to produce offspring that did not contain any foreign Arabidopsis genes.

According to an ETHZ press release on Wednesday, amylose-free cassava is not a new invention, as such plants have been produced through classical breeding alone. However, the researchers note that the genetic modification approach, which requires a few months and a few plants, is much more efficient than classical breeding, which can take years and thousands of plants.

They also state that the method could be used in other plants to expand produce diversity and support an increasing global population.

The research has been published in the open access journal Science AdvancesExternal link.