How Some People Function on Little Sleep: Gene Mutation Linked to Short Sleep Duration

Some people seem to be able to function well on little to no sleep. Those early-morning risers are the envy of many around them. Now, though, scientists have found that there may be a genetic basis for being able to function normally despite a lack of sleep.

The researchers turned to 100 pairs of twins for this particular study, including 59 monozygotic pairs and 41 dizygotic pairs. All of these pairs of twins were the same sex and were healthy with no chronic conditions. In all, the scientists measured nightly sleep duration at home for seven to eight nights with actigraphy. The researchers also examined the response to 38 hours of sleep deprivation and the length of recovery sleep in a lab.

While individual sleep needs varied, the researchers did find a small population of adults that routinely obtained less than six hours of sleep per night without any complaints of sleep difficulties and no obvious daytime dysfunction. What was more interesting was that the researchers found a twin with a variant of the BHLHE41 gene, called p.Tyr362His, who only needed a nightly sleep duration of about five hours. The non-carrier twin, in contrast, slept for about six hours per night. The scientists also found that the twin with the gene mutation had 40 percent fewer average lapses of performance during 38 hours without sleep.

"This work provides and important second gene variant associated with sleep deprivation and for the first time shows the role of BHLHE41 in resistance to sleep deprivation in humans," said Renata Pellegrino, one of the researchers, in a news release.

The findings reveal that while sleep is a biological requirement, different people have different needs. Not only that, but there are some individuals who have a "leg-up" genetically when it comes to functioning on less sleep than others.

The findings are published in the journal Sleep.