Genetically modified tomato
The first trial genetically modified food was a tomato engineered to have a longer shelf life (the Flavr Savr), which was on the market briefly beginning on May 21, 1994.
[6] In 1994, the Flavr Savr became the first commercially grown, genetically engineered food to be granted a license for human consumption.
[7] The polygalacturonase enzyme degrades pectin, a component of the tomato cell wall, causing the fruit to soften.
[12] Scientists in India have delayed the ripening of tomatoes by silencing two genes encoding N-glycoprotein-modifying enzymes, α-mannosidase and β-D-N-acetylhexosaminidase.
The fruits produced were not visibly damaged after being stored at room temperature for 45 days, whereas unmodified tomatoes had gone rotten.
[13] In India, where 30% of fruit is wasted before it reaches the market due to a lack of refrigeration and poor road infrastructure, the researchers hope genetic engineering of the tomato would decrease wastage.
An early tomato was developed that contained an antifreeze gene (afa3) from the winter flounder with the aim of increasing the tomato's tolerance to frost, which became an icon in the early years of the debate over genetically modified foods, especially in relation to the perceived ethical dilemma of combining genes from different species.
[16] The antifreeze protein was found to inhibit ice recrystallization in the flounder blood, but had no effect when expressed in transgenic tobacco.
A gene from rice (Osmyb4), which codes for a transcription factor, that was shown to increase cold and drought tolerance in transgenic Arabidopsis thaliana plants, was inserted into the tomato.
[28] When the cell wall proteins, polygalacturonase and expansin are prevented from being produced in fruits, they are less susceptible to the fungus Botrytis cinerea than normal tomatoes.
In 2000, the concentration of pro-vitamin A was increased by adding a bacterial gene encoding phytoene desaturase, although the total amount of carotenoids remained equal.
Sue Meyer of the pressure group Genewatch, told The Independent that she believed, "If you change the basic biochemistry, you could alter the levels of other nutrients very important for health".
They partnered with a company in Canada called New Energy Farms to grow a large crop of blue tomatoes, from which to create juice to test in clinical trials on the way to obtaining regulatory approval.
[40] In 2021, Japanese Sanatech Seed issued Sicilian Rouge High GABA tomato variety with increased gamma-aminobutyric acid levels.
