We know from the Fugu (pufferfish) genome that vertebrate genomes can get away with almost no junk. And before people say "well, that's just a fish, not an amaz

We know from the Fugu (pufferfish) genome that vertebrate genomes can get away with almost no junk. And before people say "well, that's just a fish, not an amazing human", realize that from the larger evolutionary perspective, the difference between a fish and a human is almost nothing. There is no particular reason to imagine that "you won't have a functional human" without the vast majority of junk DNA. Obviously there would be ethical concerns for doing this experiment, but the fact that onions can have huge genomes and fish small ones is pretty good evidence that there is no correlation with the amount of junk and functionality.