Can CRISPR feed the world?

As the world's population rises, scientists want to edit the genes of potatoes and wheat to help them fight plant diseases that cause famine. 

By 2040, there will be 9 billion people in the world. "That's like adding another China onto today's global population," said Professor Sophien Kamoun of the Sainsbury Laboratory in Norwich, UK.

Prof. Kamoun is one of a growing number of food scientists trying to figure out how to feed the world. As an expert in plant pathogens such as Phytophthora infestans – the fungus-like microbe responsible for potato blight – he wants to make crops more resistant to disease.

Potato blight sparked the Irish famine in the 19th century, causing a million people to starve to death and another million migrants to flee. European farmers now keep the fungus in check by using pesticides. However, in regions without access to chemical sprays, it continues to wipe out enough potatoes to feed hundreds of millions of people every year.

In the early stages of the project, scientists in another lab discovered a ground-breaking gene-editing technique known as CRISPR-Cas which allows scientists to delete or add genes at will. As well as having potential medical applications in humans, this powerful tool is unlocking new approaches to perfecting plants.

One of the simplest ways to use CRISPR to improve plants is to remove a gene that makes them vulnerable to infection. This alone can make potatoes more resilient, helping to meet the world's growing demand for food.

The resulting crop looks and tastes just the same as any other potato. Prof. Kamoun says that potatoes which are missing a gene or two should not be viewed in the same way as genetically modified foods which sometimes contain genes introduced from another species.