With the help of fruit flies, scientists found the genes that are responsible for why some people need to sleep more while others don't. Understanding the sleep process of humans could result in better treatments for some sleep disorders.

Short Sleep, Normal Sleep, Long Sleep

As children, people are told that eight hours is the ideal amount of sleep an individual needs in order to rest well. As the years go by and people get older, this changes to meet the body's needs. The problem with the supposed ideal amount of sleep is that some people really tend to sleep longer than the supposed ideals, whereas others need just a few hours in order to feel refreshed.

In order to understand why this is so, researchers conducted an experiment with the help of fruit flies. They did so by breeding 13 generations of fruit flies that were long sleepers, moderate sleepers, and short sleepers, with long sleepers able to sleep for 18 hours and the short sleepers able to get by with just three hours of sleep. They then analyzed the entire genome sequences of the flies in order to spot any differences.

Sleep Genes

As it turns out, there are distinct genetic differences between long and short sleepers that could perhaps explain the differences in sleep needs. When comparing the genetic data of long and short sleepers, researchers identified 126 differences in the genes said to be responsible for sleep duration, with some of the genes responsible for brain functions such as memory and learning.

What's more, researchers also found that the life spans of flies that are short and long sleepers are not significantly different from that of normal sleepers. This suggests that being a particularly long or short sleeper has few consequences, be it beneficial or detrimental, compared to being a normal sleeper. Interestingly, researchers did not alter or engineer the genetic material of flies, meaning that all the genes they studied are naturally occurring.

"Until now, whether sleep at such extreme long or short duration could exist in natural populations was unknown," said Susan Harbison PhD, leader of the study.

Importance Of This Research

Because of this breakthrough, researchers believe that it could lead to understanding the true purpose of sleep and possibly aid in developing new ways to treat sleep disorders such as narcolepsy and insomnia. What's more, it would allow people to see that different people have different sleep needs. That way, people can get the proper amount of sleep without worrying of fatigue or brain cannibalization due to sleep deprivation.

The study was funded by the Intramural Research Program of National Heart, Lung, and Blood Institute and is published in PLOS Genetics.