PAP1
Arabidopsis MYB transcription factorProduction of Anthocyanin Pigment 1
Overexpression produces deep purple anthocyanin accumulation in leaves. Real, well characterised, widely used as a visual reporter of transformation.
Science
Gene editing in
real food crops.
Genome editing of food crops is not speculative. Edited tomatoes, mustard greens, soybeans and corn are on sale in several countries right now. Here is what has actually been approved, which genes were changed, and how the rules differ by region.
Approved products
Already on the market.
| Product | Crop | Country | Year | What was edited | Status |
|---|---|---|---|---|---|
| Sicilian Rouge High GABA | Tomato | Japan | 2021 | Sanatech Seed / University of Tsukuba. First CRISPR-edited food sold to the public anywhere. GABA accumulates from a targeted edit to the C-terminal autoinhibitory domain of glutamate decarboxylase. | Sold direct to consumers from September 2021 |
| Conscious Greens | Mustard greens | United States | 2023 | Pairwise. Reduced pungency by knocking out the myrosinase-pathway genes that produce the peppery bite, making raw greens palatable. | First CRISPR-edited food in the US foodservice market |
| High-oleic soybean oil | Soybean | United States | 2019 | Calyxt. TALEN editing of FAD2 to raise monounsaturated fat and remove trans fats, replacing hydrogenation. | First gene-edited food ingredient in the US |
| Waxy corn | Corn | United States | 2021 | Corteva. Knockout of the waxy gene for high-amylopectin starch used in food texture and industrial applications. | Commercialised for industrial starch |
| Non-browning banana | Banana | Philippines | 2021+ | Tropic Biosciences. Silencing of polyphenol oxidase (PPO) to prevent enzymatic browning after peeling. | Under regulatory review in multiple markets |
| Blight-resistant potato | Potato | Various | 2020+ | Multiple groups. Stacked edits to susceptibility genes (e.g. DMR6 homologues) for late-blight tolerance. | Field trials in several countries |
Dates are first regulatory approval or first sale, whichever came first. This is not an exhaustive list — dozens of further edits are in field trials or pre-market review.
Why it is done
What editing actually solves.
Nutrition
The GABA tomato raises a compound associated with blood-pressure regulation. High-oleic oil removes trans fats entirely. Neither needed a foreign gene.
Shelf life
Knocking out polyphenol oxidase stops cut fruit browning. Less waste between field and plate, which is a supply-chain problem as much as a consumer one.
Disease resistance
Editing susceptibility genes gives durable blight and mildew tolerance, reducing fungicide use. This is the largest category of real investment.
Climate resilience
Drought and heat tolerance traits, plus reduced-input varieties that hold yield with less fertiliser.
Taste and texture
Conscious Greens removed the peppery bite from raw mustard greens without breeding out the nutrition over generations.
Industrial feedstock
Waxy corn for starch. Edited composition is often cheaper than separating fractions downstream.
Real targets
Six genes that actually exist.
GA20ox
Gibberellin biosynthesisGibberellin 20-oxidase
Partial knockdown reduces internode length, giving compact plants. This is the mechanism behind many semi-dwarf crop varieties.
EIN2
Ethylene signallingEthylene Insensitive 2
Loss of function blocks ethylene perception, delaying ripening and browning. Real targets exist in tomato and other fruit crops.
PPO
Enzymatic browningPolyphenol oxidase
The gene responsible for cut fruit going brown. Silencing it is the basis of the non-browning apple and mushroom, and the banana in trials.
FAD2
Lipid metabolismFatty acid desaturase 2
Knockout raises oleic acid and lowers polyunsaturates. The basis of high-oleic soybean and canola oils.
GAD
GABA biosynthesisGlutamate decarboxylase
Removing the autoinhibitory domain raises GABA accumulation. The edit behind the Japanese CRISPR tomato.
These are characterised genes with published literature and verified genomic coordinates. Full identifiers and accession numbers are on NCBI GenBank — a search on the gene symbol plus your crop of interest will find the sequence.
Regulation
The rules are
wildly different.
- United States
- USDA-APHIS SECURE rule (2020). Many edits that could have been achieved by conventional breeding are exempt from regulation entirely. FDA consultation is voluntary.
- Japan
- Notification to the government, not a full safety review, for edits that do not introduce foreign DNA. This is how the GABA tomato reached shelves quickly.
- European Union
- Treated as GMOs following the 2018 CJEU ruling. Effectively a barrier to commercial cultivation, with policy still under active negotiation.
- United Kingdom
- Precision Breeding Act (2023) creates a separate, lighter pathway for plants edited to be equivalent to conventionally bred varieties.
- Practical upshot
- The same edit can be a supermarket product in one country and a regulatory non-starter in another. Geography, not biology, decides.
What this page is not
A limitation worth stating.
None of the above is a home protocol. Every product listed was developed by teams with contained facilities, plant transformation infrastructure, containment permits and years of regeneration and field trial work. There is no version of this that happens with pipettes on a kitchen counter — not because the science is secret, but because protoplast regeneration and containment are the hard parts, and they do not compress.
What a countertop system can do is grow the resulting variety well. That is the half of the problem DarkGrow actually solves: the 10 L reservoir, the chiller loop, the dosing. The genetics is other people's work, done in other people's buildings, under other people's licences.
If you want to read the primary literature, the two papers behind the acetate discussion are linked from the research page. For edited crops specifically, start with the product approval documents — they are public and they name the exact gene and edit.
Discuss it on
the forum.
A genetics category is open for reading group threads and questions about the primary literature.