This xkcd cartoon is interesting:
…both for the science behind it (feel free to demonstrate your superior grasp of biomedical research by understanding this better than I do – which is to say, at all) and the commentary about the strip, which ranges from “ZOMG you’re making jokes referencing cancer you bad person” to “ZOMG you have completely gotten wrong three or four arcane bits about biomedical research you bad person” – although admittedly both of those types of responses are being treated with mockery that was more gentle than it could have been. All I know is, I think that the possibility was first brought up in “Our Neural Chernobyl.”
Hmm. I should look up the date that that story was supposed to have taken place.