Scientists Discover Narcolepsy Gene

Dealing With the Drugs Difficult, Too

"Untreated, even crossing the street is a challenge," Smith said. "If the light changes to yellow, you worry, 'Am I going to get across?,' and that can cause cataplexy."

Drugs helped, but Smith decided to stop using the high doses of antidepressants that mitigate the narcolepsy symptoms when she got pregnant with her second child. Even today, the drug treatments for narcoleptics are rife with side effects.

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"It's brute force. It's hitting them over the head with medicine to manage it," said David Carley, Medicine and Pharmacology director at the Center for Narcolepsy, Sleep and Health Research at the University of Illinois at Chicago.

"Basically we're at the point of saying, 'OK, I know you tend to fall asleep. I'm going to overcome that by just bulldozing your central nervous system,'" Carley said.

Narcolepsy specialists borrow drugs made for other medical conditions that happen to take over the body's sleep cues, Carley said. With narcolepsy, the person doesn't sleep more, but just sporadically and suddenly.

Animal testing has started to explain aspects of narcolepsy, but even with treatment, many patients still suffer from debilitating exhaustion trying to fit with society's work days.

"In humans it's not a genetic mutation that causes narcolepsy," said Mignot, the director of the Center for Narcolepsy at Stanford. "It's an autoimmune response."

Finding the Cause of Narcolepsy

Narcolepsy researchers, actually at Mignot's lab, discovered the immune response explanation only eight years ago. They found that, somehow, the body was destroying nerve cells in the brain responsible for creating a chemical called hypocretin involved in sleep. By the time someone develops narcolepsy symptoms, 90 percent of the nerve cells n their brain that can create hypocretin are gone.

"But we still don't it understand it very well," Mignot said. "That's why it's very important to look for all the genes, so we know how these genes are involved in the immune response."

While the new genetic link to narcolepsy may help doctors to understand how the disorder develops, and therefore make better drugs to treat it, researchers do not expect that it will help diagnose patients -- and diagnosis is a serious problem.