Sleep Deprivation Tolerance May Be Genetic Oct. 25, 2010 -- A genetic difference may make some people more likely to suffer the ill effects of sleep deprivation.

Researchers have found that people with a certain gene were more likely to feel sleepy or fatigued but have difficulty sleeping after only four hours of sleep, compared to people without the gene.

“This gene may be a biomarker for predicting how people will respond to sleep deprivation, which has significant health consequences and affects millions of people around the world," researcher Namni Goel, PhD, of the University of Pennsylvania School of Medicine in Philadelphia, writes in a news release. "It may be particularly important to those who work on the night shift, travel frequently across multiple time zones, or just lose sleep due to their multiple work and family obligations."

The gene, DQB1*0602, is closely related to the sleeping disorder narcolepsy, which causes excessive daytime sleepiness. Between 62% and 88% of people with the gene have the sleep disorder.

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