genetic modifacations are a gray area for me our DNA is very vyer complex and we don't know enough about what we change to be sure that it hasn't made any harmfull changes but if a fish was GM and we could be sure that it wouldn't hurt or cause and problems then i would buy them.
Reasearch on any animal helps us to undersand outselves because everything in nature works on the same level even though they look different and think differently. and example of this is ppl wit genetic dissorders in most of them ony one tiny set of genetic material is changes and the results can be extensive, same with everything.
apart from helping ppl it also helps us to understand the animals that are being tested.
but animal testin is wrong if the animal suffers.