Why do some people need so little sleep? Chronobiology researchers may have discovered a genetic mutation that creates short sleepers, i.e. people who need very little rest.
What could you do with your extra time if you didn’t need to sleep? These extra hours could be spent studying, earning extra income or simply enjoying leisure activities. Most people need around eight hours of sleep a night to thrive, but there are notable exceptions. Some men and women, called “short sleepers,” need only four to six hours of sleep a night. While the rest of us sleep at night, others are free to spend the extra hours however they wish. Researchers may have unlocked the secret behind the genetics of the lucky individuals with low sleep needs, suggesting that a genetic mutation may be responsible.
The Biology of Short Sleepers
Short sleepers have been studied by scientists since they were discovered in the ’90s. While most of us can barely survive on four hours of sleep, others seem to actually thrive on it. These people make up a tiny minority of the world population, less than 1 percent. Scientists were baffled that they could thrive on very small amounts of sleep and suggested that a genetic mutation might be responsible. Evidence suggests that this hypothesis may be correct, as researchers have discovered the gene likely responsible for this trait.
DEC2: The Efficient Sleep Gene
Researchers noticed that a mother and daughter who both needed very little sleep shared a mutation in a gene known as DEC2. When they bred mice with this genetic mutation, the mice also needed very little sleep. On physical examination, the gene mutation had other interesting effects. The mice had enhanced connections between parts of the brain that coordinate sensation and memory. They also were not likely to be overweight, an observation that also generally holds true for human short sleepers.
How can a person sleep as little as half the recommended time with no health effects? Scientists believe that short sleepers may simply sleep more efficiently. The enhanced connections to areas of the brain controlling memory hint that this may be a very important part of the puzzle, as memory consolidation is one of the most important tasks we perform while sleeping.
Can You Become a Short Sleeper?
Are you a short sleeper? Scientists are quick to point out that not everyone who sleeps four hours a night has this mutation. In general, people who exist on very little sleep fall into three categories: those with sleep disorders, those who are actually short sleepers and those who believe they are short sleepers yet suffer physical effects of their lack of quality sleep. Although we now know the gene responsible for needing less sleep, there is still no way to induce a genetic mutation in humans. Thus, while you may wish to have a few extra hours in your days, you will probably continue to need a solid eight hours of sleep for the foreseeable future.