Early Risers Have Mutated Gene

John Roach reports in National Geographic News:

“I’m wide awake and ready to paint the house,” the 49-year-old Colchester, Vermont, resident said. “I don’t need a cup of coffee to get going, not at all. But between 4:00 and 5:00 [p.m.] you might have to nudge me with an elbow.” Middlebrook suffers from what is known as familial advanced sleep phase syndrome, or FASPS. Her body’s clock is out of sync with the sleep-wake rhythm most of the world lives by. She goes to bed each night between 5:30 and 7:30 p.m. and wakes in the wee hours of the morning.

“The net result is you can feel very isolated,” Middlebrook said. “Who wants to party at three in the morning? Nobody I know, and I’m not headed to the local bar to see who’s still there.” Instead, she quietly cleans the house, makes breakfast, or cuddles up with a book.

About three-tenths of a percent of the world’s population lives like this, including two of Middlebrook’s sisters, her daughter, and her mother. “Their whole clock is shifted,” said Ying-Hui Fu, a neuroscientist at the University of California, San Francisco. Fu and colleagues report in tomorrow’s issue of the science journal Nature on a newly discovered mutation to a single gene that they say causes FASPS. In addition to FASPS, four of the five individuals showed signs of depression, Fu said. “[The depression] is most likely caused by the same thing,” she said. “As we probe deeper into how this mutation causes sleep problems, it very likely will also give insight to how the mutation will cause depression.”

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