We can now take data from a computer and synthesise DNA for a cell from basically nothing, load that DNA into a 'blank' cell and start it up, making it grow and replicate - almost like making life!
We can use CRISPR/Cas9 to accurately cut and paste active DNA anywhere we want with high precision.
All these tools are ready, we just have to work out how to use them
CRISPR/Cas9 is more precise than technologies before, but still not perfect: http://www.nature.com/news/enzyme-tweak-boosts-precision-of-...
These things have a way of being impossible until they are not. It used to be impossible to communicate with someone a great distance away, then we invented the telegraph. It used to be impossible to see someone at a great distance, then our seemingly-unrelated breakthroughs in network technology brought us easy consumer video chat.
https://en.wikipedia.org/wiki/Timeline_of_medicine_and_medic...