Mouse with Ear on Back: "Hey I heard that I'm gonna get a transplant"
Mouse with Nose on Back: "Really? I thought something smelt a little fishy round here"
Mouse with Ear on Back: "We can never trust these mad men scientists"
Mouse with Nose on Back: " Ah yes, you're right... *sniff sniff* ... I SMELL CHEESE!"
It isn't rightful, but what else could we possibly test these things upon? Are there people willing to put their lifes on the line? That's a good question.
I still do kinda anticipate the nanobots. And those will probably be tested with humans.
"With all the respect, JPIV, could you please start rolling?"- Dino_Slayer
For some things, SOME people would be willing to do it. For example, some people will actually DO the growth-gene thing... Some will even want to design their own ideal children... and so you never know...
The thing that would turn people off of it if it goes wrong. It may not turn out to be an enhancement but rather a hindering feature...or even something that kills you.