This was a while ago and I can't remember very much, but I really loved this book but it was lost in a car crash :(
Anyway, so the main character was grown and genetically engineered. At one stage he is walking along train tracks with another character deep in thought but never loses his balance which impresses the other character.
The book is set in the near(ish) future. There's two main branches of development, which I think have both built a colony ship for some reason; there's a technological side, metal and computers, that sort of stuff, and a more 'green' side, they've made trees more efficient, grow in the shapes of furniture and the like, their entire spaceship was grown rather than built. (Very similar to the "Adamist" and "Edenist" cultures in the Night's Dawn Trilogy)
I know it's not much to go on, but I hope someone has some sort of idea.