Scientists have already assembled the simpler virus this way but in a fundamental sense a virus is not alive. It is a type of parasite, as it needs a host cell to live. The experiment to create a living organism from its basic chemical building blocks would be the culmination of science's view, held by the ancient Greeks and again since the renaissance, that living things are simply machines. It is a view of life that will upset many. You could say the big question is whether higher animals like ourselves are just more complicated than bacteria or fundamentally different.
Humans are, of course, very different from bacteria in many ways.
We have 100,000 genes not just a few hundred. With our gene set, or genome, comes a larger and more complicated body with a sophisticated brain. The BBC is not responsible for the content of external internet sites.