DNA ??

DNA ?? - On this day in 1953, Cambridge University scientists James D. Watson and Frances H.C. Crick announced that they had determined the double-helix structure of DNA. Now, I'm fairly certain that this structure ISN'T a double-helix. But it's my challenge and I make the rules so it qualifies. Considering this was more or less a grab-shot, I really like the symmetry of it. Incidentally, Watson is still alive. He's 84. I didn't know that.