Did scientists develop genetically modified (GMO) tomatoes containing fish genes, which is why if you slice them up and put them in saltwater they start swimming? No, that's not true: there are no fish genes in tomatoes sold to the public and if there were, they would have to be labeled accordingly.
The claim appeared in a video (archived here) published on TikTok by user @manuel.mar14 on August 14, 2023, under the title "Look what you're eating". The caption read:
All living beings have their genome organized into a set of genes, DNA pieces with instructions for the functioning of the cell. Through biotechnology, genes from other beings can be inserted into plants and animals, which is known as "transgen."
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Tue Aug 15 10:43:23 2023 UTC)
The story took off several years ago when scientists considered the possibility of inserting an Arctic flounder gene into tomatoes to give them an anti-freeze protein that would help farmers save their crops in case of a sudden freeze. "Preliminary experiments showed that in plants this protein was not effective in preventing ice crystal formation and the project was dropped," McGill University further explained. Tomatoes containing fish genes never ended up in supermarkets.
Now, videos showing how a slice of tomato is "swimming" in saltwater have resurfaced and become viral, in Romanian, as well as other languages. But the GM tomatoes never swam. There is no proof these images are real, and the fact that the footage is blurred at certain times in the video indicates it was edited.
Genetic Literary Project also explained that taking a gene from one being/ plant and inserting it into another does not modify the DNA of the recipient. "Inserting a fish gene into a tomato does not make a tomato "fishy" in the same way that humans cannot breathe underwater. We share some genes with fish, but that doesn't make us fish."
