Why would you need an embryo to select a genotype? You don't need to physically embody genomes in embryos just to get iterative selection.... you can do that in

Why would you need an embryo to select a genotype? You don't need to physically embody genomes in embryos just to get iterative selection.... you can do that informatically before you get to the stage of somatic cell nuclear transfer to inject DNA/genome into the cell. Anders should aspire more towards George Church and less towards Nick Bostrom. (I know he wasn't on the paper, but whatever. It's been on my mind.) While I am at it: here's some (typical disclaimer applies) notes on open-source DNA synthesis machine design: http://diyhpl.us/wiki/dna/synthesis/notes/ http://diyhpl.us/wiki/dna/synthesis/notes/ Re: Genotype/phenotype; once we find stable phenotypes, we should make more reliable structures on top of those phenotypes, instead of messing with the genetics. For example, for protein-based molecular nanotechnology, nobody really wants to spend their time doing a trillion different folds in simulation or in the lab just to find their target structure. Instead you will have to skip tweaking genotypes (because of the large costs of exploring the genetic landscape (really, take whatever you can get)) and just use lego brick phenotypes... at least for nano/molecular structures (nanotech). Other changes require exploration of evolutionary/genetic landscape, until heuristics get better if ever, which will continue to be expensive even with $1/genome synthesis costs.