Evolution and selective breeding don’t arbitrarily modify DNA. The actual methods are small random changes, copying from some other location possibly backwards, or removing segments. GMO significantly expands what kinds of changes are possible.

In practice the difference is generally not that significant, but there is some increase in risks.

Personally, I would prefer a different label for new GMO foods. Presumably, the odds of finding an undiscovered issue drops over time. So using a different label for the first 20 years is reasonably appropriate. Plenty of people are going to take slightly higher risks, so they can benefit from and thus test new cultivars.

> Evolution and selective breeding don’t arbitrarily modify DNA.

Except for random mutations, which are, well, random changes to DNA.

There is a reason the nightshade family[1] is so varied.

https://en.wikipedia.org/wiki/Solanaceae

Small random changes yes, but long specific sequences become exponentially less likely. People on the other hand can decide to add say the first 100,00 digits of Pi or some other marker for internal use. Picking a useful sequence is hard, but we have the technology to add any specific sequence as long as the plant can survive it.

So it’s not just a question of random chance adding something harmful at this point, but also malicious actors. Someone could easily decide to try and reduce the human population by reducing fertility or whatnot and new GMO crops aren’t tested for such things.

Do you know how they discovered methods of genetic modification? Retroviruses in nature. Look at HPV for one as a cause for cancer and the number of viruses embedded in human DNA. Evolution includes all of those.

Of course /nothing/ meets the goal posts of "arbitrary" including state of the art genetic modification.

We have moved past simply copying and pasting DNA and can now add arbitrary genetic sequences to any organism. Natural rice retroviruses are unlikely to carry jellyfish DNA let alone something designed from scratch.

As I said it’s probably not that meaningful of a difference, but malicious actors have serious tools to work with here not just random changes.