There was a very funny old sci-fi story about scientists on some kind of space colony who just ... wanted fresh milk. And the point of the story was just how much of the actual cow they had to replicate (in semi-isolated containers) to end up making that milk.
So you want an organ, sure, but you're going to need something like blood flowing through it so it doesn't just flat up die. That means that it is going to need oxygen -- so you're stuck replicating some kind of pulmonary system, and then you're going to need to put various nutrients in it, and then you're going to need to remove waste products, so you're definitely getting a liver and a kidney out of that ... and then just making the red blood cells requires bone marrow ...
My guess is that anacephalacy would be studied and replicated to grow humans with only a minimal brainstem, with probably a nubbin of various hormonal systems tacked on. We could get to that a lot faster, I think, than single organs.
Sounds difficult if you want to replicate organs 1-1, but what makes sense for human/animal bodies isn't necessarily the best way for labs. Maybe a single large biochemical reactor can solve half of those issues? There are already well established procedures for growing cell cultures and multiple startups that want to grow muscles (meat) or other organs. I don't know details - not my field - but pretty sure a large part of those seemingly hard problems are already solved/worked around.
There was a very funny old sci-fi story about scientists on some kind of space colony who just ... wanted fresh milk. And the point of the story was just how much of the actual cow they had to replicate (in semi-isolated containers) to end up making that milk.
So you want an organ, sure, but you're going to need something like blood flowing through it so it doesn't just flat up die. That means that it is going to need oxygen -- so you're stuck replicating some kind of pulmonary system, and then you're going to need to put various nutrients in it, and then you're going to need to remove waste products, so you're definitely getting a liver and a kidney out of that ... and then just making the red blood cells requires bone marrow ...
My guess is that anacephalacy would be studied and replicated to grow humans with only a minimal brainstem, with probably a nubbin of various hormonal systems tacked on. We could get to that a lot faster, I think, than single organs.