CG
Somebody: Essentially you're endorsing the precautionary principle when it comes to transgenic animals (and plants). In this you're in keeping with the guiding principle of, for example, the U.S. FDA. The problem with that is that it prioritizes the potential of downsides while minimizing the negative effects of the status quo.
This isn't an issue with this salmon per se; although, it has to be said, the detrimental effect of GM crops so far has been negligible, after everything's been said and done. Rather, the issue is whether the left should adopt a default position of not just being skeptical, but resistant to biotechnology simply because it is being utilized by the private sector in our still capitalist society.
Personally, I think the status quo is pretty lousy. More people die from causes that are primitive in nature (that precede modern industrial and post-industrial society, and at best are simply sustained by capitalism) instead of being products of human activity. Yet if you read the environmentalist literature, you might suppose that the great bulk of the ills of the world are products of modern man.