If You Only Need 5 Hours Of Sleep, It Might Be In Your Genes

This gene makes people able to live off as little as 4 hours of sleep.

Last updated on Mar 22, 2023

woman smiling in bed sleeping Prostock-Studio / Shutterstock

If you find yourself waking up at 4 or 5 AM after going to sleep around 11 PM or midnight, rest assured that you aren't the only person experiencing this. You may, in fact, have a rare gene known as the "short sleep gene."

Researchers have determined our circadian rhythm might be genetically predetermined and sleep patterns are passed down hereditarily.

RELATED: Why So Many People Wake Up For An Hour In The Middle Of The Night... On Purpose


What is the short sleep gene?

The short sleep gene is a genetic mutation that allows people to function with little amounts of sleep without any ill effects. That is, people can sleep for less than 6 hours a night and feel well rested.

They don't feel deprived of sleep or tired at all. In fact, they feel completely refreshed and ready to tackle the day ahead with as little as 4 hours of sleep. The mutation is inherited.

Researchers have discovered several "short sleep" gene mutations.

Ying-Hui Fu, from the University of California, San Francisco, and her colleagues, have been seeking out and studying families in which some people seem to need less sleep than normal.


Through this research, Fu has discovered several genetic mutations that make family members able to survive and thrive off just a few hours of sleep a night.

Fu’s team first reported in 2009 that a mutation in a gene called DEC2 caused short sleepers to stay awake longer. Then, Fu discovered that a mutation in the ADRB1 gene allowed 12 members of a family to sleep as little as 4.5 hours per night without feeling tired.

Later, a third mutation in a gene called NPSR1 caused members of another family to average between 4.3 and 5.5 hours of sleep per night found by both Louis Ptáček, MD, and Fu.

Short sleep genes are associated with increased productivity.

While the gene might seem like your worst nightmare if you dread getting out of bed in the mornings, those with the gene seem to put those extra hours to good use.


Researchers discovered many short sleepers were ambitious, Type A personalities, but also incredibly positive, outgoing, and optimistic. Many were marathon runners with positive physical and physiological traits that may be linked to their sleep patterns.

These findings suggest that the genetic mutation prevents short sleepers from experiencing any adverse effects of sleep deprivation, which is typically associated with obesity, diabetes, cardiovascular problems, depression, and cognitive deficits.

Short sleep genes prevent memory deficits.

Another win for short sleepers is their phenomenal memories. Not only do they have more time awake to make these memories, but they’re also actually more likely to recall them in later years!

Fu said some 90-95% of the people in the studies had these common characteristics and were able to avoid memory deficits associated with sleep deprivation.


To confirm this research, memory tests were performed on mice who were engineered to possess the gene.

Mice were placed in a chamber and gently shocked with an electrical current while exploring their surroundings.

When the normal mice were well-rested, they were able to remember the shock and refused to roam around after being returned to the chamber. Sleep-deprived mice, on the other hand, didn't exhibit fear and seemed to forget the shock when they were returned.

However, carriers of the mutant version of NPSR1 did remember the electrical shocks, even after being sleep deprived.

RELATED: The Ideal Room Temperature For A Good Night's Sleep, According To Experts


How rare is the short sleep gene?

The gene that was first reported, the DEC2 gene, is actually extremely rare. It is believed that only about 1% of the world's population are true short sleepers and have this mutated gene.

To give you a sense of just how rare, the gene occurs in fewer than one in 4 million people.

The NPSR1 and ARDB1 mutations are equally as rare.


How do I know if I have the short sleep gene?

There really isn't a proven way to know if you're a short sleeper or if your body has just gotten accustomed to little sleep, unless you go through DNA testing which can cost a pretty penny.

However, if you have several of the usual traits of short sleepers, the possibility that you are one is high. You could still just have a sleep disorder or sleep deprivation, but it's a good place to start.

You may have the short sleep gene or be a natural short sleeper if:

  • You consistently sleep for six hours or less and are naturally are able to wake up without an alarm.
  • You have abnormal sleep cycles.
  • After less than 6 hours, you wake up feeling refreshed and awake.
  • You retain the ability to think clearly despite sleeping very little.
  • You don’t rely on caffeine or taking naps to get through the day.
  • You have always slept less, even as a child, and were completely fine.

RELATED: What The Time You Go To Sleep Reveals About Who You Are


Alice Kelly is YourTango’s Deputy News and Entertainment Editor. Based in Brooklyn, New York, her work covers all things social justice, pop culture, and human interest.