The mouse didn't. And then it did. Does it portend anything for you?
A cure for baldness is the holy grail of the quest for cosmetic pharmaceuticals. Various substances have been found to work somewhat, some of the time, but none has done the job luxuriantly all of the time. Unless you're a mouse in a lab.
Researchers have just discovered a single protein that can turn a completely hairless mouse into a completely hairy one. Could the same trick work for millions of bald men? Not yet, but perhaps someday. It's certainly the most hair raising discovery to date. You can read more about it here.