The problem with this sort of genetic research is that it won’t stop with merely the creation of organs for transplant and you know it. The genie’s out of the bottle and all manner of hybridization for other purposes will be done, I suspect first out of the box will be an attempt to create superhuman soldiers. Your trust in the innate benevolence of medical science is touching, but the past century contains its own set of horrors that tend to indicate otherwise.
Good God, why does EVERYONE leap to that..?
It is freaking STAGGERING the variety of benefits of this tech.
Fire burns us, has wiped out entire cities, but does that mean cave-men should have banished FIRE..?
When telephones were first invented people said, "Tuberculosis will spread like wild-fire, the speaker talks directly into the EAR of the listener..!"
When they invented trains horsemen said they'd never catch on, "No one will be able to breathe, as the wind in passengers' faces will be too fierce..."
When new tech comes out there is ALWAYS fear.
The day after the first flight by the Wright Brothers the front page of the NYT featured long stories by phycicists about how flight by men not only hadn't occured but was IMPOSSIBLE.