DNA replication is a verrrrry fragile thing. If replicated correctly, it can lead to organ transplants and skin grafting and have all sorts of medical advantages. DNA replication could even lead to human cloning, but scientists haven't figured that out yet. Point is, if you replicate skin DNA for a skin graft of a burn victim, it can be super tricky if it gets messed up. It can mess up the skin, not fit together properly, etc etc. There's a lot of problems with things like that. And if DNA replication ever developed where we could clone blood and replicate that, that would be another tricky thing. If one little thing was off, the blood could actually kill you.
