The very first post I made on the Odeck was on this cool story about how narcolepsy may actually be caused by the immune system. This hypothesis came about after researchers saw a spike in narcolepsy in Scandinavia and China after injection with an H1N1 vaccine, or infection with H1N1, respectively.
Totally makes me sad to see this happen, but I'm also glad that the authors did the right thing. They saw that things weren't working, and they made sure to let the scientific community know.
And as noted by Thomas Scammell from Harvard in the Science article:
The retraction "does not undermine the fundamental hypothesis" that narcolepsy is caused by an autoimmune reaction "all that dramatically," Scammell says. He and others may consider different causes of narcolepsy, however. "Maybe there's a very selective virus that's very fond of targeting and then killing" hypocretin neurons, he says.