I don't agree that tissue renewability is the correct sole factor in determining whether said tissue should be for sale. I think that donor risk is much more important. I consider this to be a bioethical issue but I think it's also pretty political so I'll probably refrain from making much of an argument here.

I don't do liver transplant so I'm at the limit of my knowledge re: number of liver donations, but I would guess that it has to do with the fact that the donated segments do not regrow; the liver regains function, but not form.

> I think that donor risk is much more important.

It would be important to me certainly, if I was considering donating.

But at the end of the day each person much decide for themself. Just like people decide on a level of risk when accepting a job.

If people are allowed to risk their life on a job to make money, they should be allowed to risk their life to donate tissue to make money.

For donations though, any significant risk is probably not acceptable, which is the current situation.