Genetic modification, in the older transgenic sense, means inserting a gene from another organism into a plant's genome — the Bt gene from a soil bacterium, for example, inserted into maize. Gene editing is different: tools such as CRISPR-Cas9 cut a plant's own DNA at a chosen location and let the plant's natural repair process introduce a small, targeted change, without necessarily adding any foreign genetic material at all. That distinction, once mostly of interest to molecular biologists, is now written directly into UK and EU law, because it changes how a crop is regulated.
- 2020 Nobel recognition
- Chemistry, for CRISPR-Cas9
- UK framework
- Genetic Technology (Precision Breeding) Act 2023
- Key distinction
- Foreign DNA present, or not
Who developed CRISPR-Cas9, and why does it matter here?
CRISPR-Cas9 as a programmable gene-editing tool was developed in the early 2010s, and the 2020 Nobel Prize in Chemistry was awarded to Jennifer Doudna and Emmanuelle Charpentier for the technique. Its importance for crops is practical rather than ceremonial: earlier gene-editing tools were expensive and slow to redesign for each new target, while CRISPR-Cas9 is comparatively cheap to retarget at a different gene, which has let far more public research institutions and smaller companies work on crop gene editing than could ever have worked on transgenic engineering at scale.
How does an edited plant differ from a transgenic one at the DNA level?
A transgenic plant carries a stretch of DNA that did not exist in that species before — a bacterial gene, for instance, sitting inside a maize chromosome. A plant produced by a targeted gene-editing technique known as a site-directed nuclease approach can instead end up with only a small deletion, insertion or substitution within its own existing gene sequence, of a kind that can be similar to mutations that already occur naturally or through older mutagenesis breeding. In many cases, once the editing tool itself has done its job and is removed from the plant through conventional breeding steps, the final variety carries no foreign DNA that a standard genetic test would flag as different from a conventionally bred plant carrying the same mutation.
How has the UK responded to that distinction?
The Genetic Technology (Precision Breeding) Act 2023 created a separate legal category in England for "precision bred organisms" — plants and animals produced by gene editing that could, in principle, have arisen through traditional breeding or natural processes, and that carry no foreign DNA. Precision-bred plant varieties can move through a notification-based route overseen by the Food Standards Agency rather than the full GMO authorisation process that still applies to transgenic crops, on the reasoning that a change indistinguishable from conventional breeding does not need the same regulatory weight as inserting foreign DNA. The Act applies in England; Scotland, Wales and Northern Ireland have taken their own positions on whether and how to follow it.
What is happening with gene editing in the EU and Japan?
The European Commission put forward a proposal in 2023 for a new regulatory category covering plants produced by certain new genomic techniques, intended to separate them from the existing GMO framework under Directive 2001/18/EC, and that proposal has continued through the EU's ordinary legislative procedure since. Japan moved earlier and more simply: its Ministry of Health, Labour and Welfare operates a notification-based system for gene-edited foods that contain no foreign DNA, and the country's first commercially sold CRISPR-edited food, a tomato bred for higher GABA content by Sanatech Seed, reached consumers there from 2021 under that route rather than through full GMO approval.
Does "no foreign DNA" mean a gene-edited crop is automatically judged safe?
No — it means the regulatory question asked about it is different, not that the safety question disappears. Most frameworks, including the UK's precision breeding route, still require a food safety assessment before an edited variety can be marketed; what changes is whether that variety is also required to go through the full environmental release and traceability regime built for transgenic organisms. The gene-edited non-browning mushroom developed at Pennsylvania State University, in which a gene for an enzyme involved in browning was switched off using CRISPR, was judged by the US Department of Agriculture in 2016 to fall outside its plant pest regulatory authority specifically because it contained no introduced genetic material — a decision about jurisdiction, not a food safety verdict issued by a food safety body.