Forget genetically modified, here’s to genetically edited

Recent advances that allow the precise editing of genomes have raised the possibility that fruit and other crops might be genetically improved without the need to introduce foreign genes, according to researchers.

Writing in Trends in Biotechnology, the team behind the new study noted that since the beginning of agriculture efforts have been made to improve the quality of fruits and crops both conventional breeding and more recently through genetic engineering, which has emerged as a major tool for introducing desirable genes in to fruit crops.

Led by Chidananda Nagamangala Kanchiswamy of Istituto Agrario San Michele in Italy the new review focuses on how recently developed genome-editing tools for fruit crop improvement could be used be used to produce fruits with new or improved traits but with higher consumer acceptance than ‘traditional’ GM technologies.

“Societal distrust for such technologies, coupled with misleading and false information regarding their safety, means that traditional GM technology has been difficult, or impossible to commercialize successfully,” wrote the team.

However, with awareness of what makes these biotechnologies new and different, genetically edited fruits might be met with greater acceptance by society at large than genetically modified organisms so far have been, especially in Europe, they said.

This could mean that genetically edited versions of GM fruits such as "super bananas" that produce more vitamin A and apples that don't brown when cut, among other novelties, could be making an appearance on grocery shelves.

"The simple avoidance of introducing foreign genes makes genetically edited crops more ‘natural’ than transgenic crops obtained by inserting foreign genes," said Kanchiswamy.

For instance, changes to the characteristics of fruit might be made via small genetic tweaks designed to increase or decrease the amounts of natural ingredients that their plant cells already make, said the team.

Away from GM and towards GE

Genome editing of fruit has become possible today thanks to the advent of new tools - including CRISPR and TALEN - and also because of the extensive and growing knowledge of fruit genomes.

So far, these editing tools have not been applied to the genetic modification of fruit crops. Indeed, most transgenic fruit crop plants have been developed using a plant bacterium to introduce foreign genes, and only papaya has been commercialised in part because of stringent regulation in the European Union (EU).

However, the researchers say that genetically edited plants, modified through the insertion, deletion, or altering of existing genes of interest, might even be deemed as non-genetically modified, depending on the interpretation of the EU commission and member state regulators.

Fruit crops are just one example of dozens of possible future applications for genetically edited organisms (GEOs), said Kanchiswamy and his colleagues.

"We would like people to understand that crop breeding through biotechnology is not restricted only to GMOs," he said. "Transfer of foreign genes was the first step to improve our crops, but GEOs will surge as a ‘natural’ strategy to use biotechnology for a sustainable agricultural future."

"Genome-editing technologies have the potential to offer the consumer products that would be difficult, or impossible to produce using traditional breeding methods, without the addition of foreign DNA typical of traditional GM," the researchers concluded. "These new crop fruits will remain biotech crops, which is largely acceptable. We suggest the name of genetically edited (GE) crops for plants created with gene-editing tools such as ZFNs, TALENs, and CRISPRs."

Source: Trends in Biotechnology

Published online ahead of print, doi: 10.1016/j.tibtech.2014.07.003

"Looking forward to genetically edited fruit crops"

Authors: Chidananda Nagamangala Kanchiswamy, Daniel James Sargent, et al