SAN FRANCISCO -- People who do not get much sleep, but are always full of energy might be able to thank their genes.
Researchers at the University of California San Francisco have discovered a second short-sleep gene called ADRB1. People that have the gene feel rested after less than 6.5 hours of sleep; most of us need at least eight hours. The gene mutation allows the individuals to get better rest even when their sleep schedules change.
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In 2009, researchers discovered a gene mutation called DEC2; people who have it feel rested after averaging only 6.25 hours of sleep.
Researchers say the better they understand the genetics behind the sleep, the more they're learning about issues that impact it, like insomnia.
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