Question

I'm the 1950s, what discovery revolutionized biotechnology?

Answer 1

It was the structure of DNA. Watson and Crick stole the credit from a woman whose name I can't remember, but basically she took really long exposure photographs (24 hours for some) and saw an X shape, which was the corresponding sign of a double helix. It was a pretty complicated method she was using and nobody had thought of using it for DNA research until then.