Well, first, it wouldn't be Christ. It would, in effect, be his twin brother. "Hi, I'm Bob, Christ's brother." Really not an appealing prospect, and imagine how Bob would feel?
Seriously, I'd be interested in seeing if there were any identifiable markers, any kind of indication that there was something more present. It's like the folks who postulate that the Shroud image was created by the energy given off during the resurrection, positing a physical mechanism for God to have used to create the image.
You mention Sci Fi. Have you ever read the book of Contact, by Carl Sagan? That well known and very public Atheist had a twist at the end of the book that they didn't go into in the movie. Contact was largely concerned with ferreting out information embedded in radio noise, using largely code breaking techniques. At the end of the book the hero has moved on and is looking at DNA. She applies the same techniques to DNA as she had to the radio signal and basically finds a picture with a sign saying "start here." Sagan says he didn't intend to write that scene, but something just pushed him to do it when he was typing. He never could explain what he'd meant by it or why he'd put it in.
Maybe there's a message waiting for us in His DNA?
Of course, Murphy's law says it would be "If you are reading this then you've done something very wrong."