Remember those people in college who could study well into the wee hours of the night, rise the next day for a vigorous early morning run, studiously attend classes, socialize with all the exuberance of a wedding party, and consistently get good grades? I do. For me—who tried hard to mimic their sleep schedule and was perpetually tired as a result—the group of them represented the Eighth Wonder of the World, and I felt totally unable to compete with them, as if they were a different species.
Maybe they chugged energy drinks ‘round the clock. Maybe they were just more determined, made of stronger stuff than I was. Maybe they were just a whole lot smarter than I was, and their semi-conscious brain could function better than my fully conscious one. You can see how comparing yourself to these rare marvels of nature can quickly lead to a downward spiral of self-flagellation and feelings of inadequacy.
Relax. You can stop beating yourself up.
Turns out, it’s not you; it’s them. Recent research conducted by Ying-Hui Fu, neurology professor at University of California San Francisco, indicates that these lucky people were born with the unusual gift of at least two mutated genes that enable them to feel perfectly rested and function normally on a mere 4 to 6 hours of sleep. Compare that to the 7 to 9 hours required by most adults, and you can see how people endowed with these prized gene variations would have a competitive advantage over the rest of us mere mortals trying hopelessly to keep up.
In a study published in Neuron’s August 2019 edition, Fu’s team worked with three generations of a family of short sleepers. Using whole exome genome sequencing—a process that reveals variations in the protein-coding region of any gene—the research team identified a rare mutation in the ADRB1 gene that was passed from one generation of this family to the next.
The ADRB1 gene helps to regulate the sleep/wake cycle and the unusual mutation to it resulted in higher levels of hormone receptors that work to wake us and keep us alert. Thus, the shorter sleep time.
This new finding grew from earlier research into what enables some people to function perfectly well on 6 or fewer hours of sleep. In 2009, Fu discovered a mutation in the DEC2 gene in a family of short sleepers. It wasn’t until 2018 that Fu was able to demonstrate how that mutation may allow short sleepers to thrive on far less sleep than most people. Using genetically engineered mice with the mutated DEC2 gene, Fu’s experiments indicated that DEC2 regulates sleep/wake duration at least in part by modulating a neuropeptide hormone called orexin. The mutation hampers DEC2’s ability to control orexin levels to produce more typical sleep durations. The higher levels of orexin result in more hours of wakefulness and a reduced need for sleep.
Only a small percentage of people can thrive on 6 or fewer hours of sleep. About 5% of the population possess the gift of short sleeper syndrome and even fewer of them—about 1%—possess the DEC2 mutation, demonstrating that there are multiple mechanisms at work in producing this remarkable ability.
Dr. Fu’s co-author, Dr. Louis Ptáček anticipates much more research into what determines sleep duration and why some people can sleep so much less than others. He says, “Sleep is complicated. We don’t think there’s one gene or one region of the brain that’s telling our bodies to sleep or wake. This is only one of many parts.”
Dr. Fu hopes that her research and that of other sleep experts will help them learn all of the components necessary for a sound sleep. Determining all of the factors that improve sleep efficiency could lead to better sleep for all of us. Scientists believe that people with short sleeper syndrome experience more intense REM sleep states leading to better sleep efficiency. Discoveries like Dr. Fu’s may one day play a role in helping people with sleep disorders that disrupt their sleep.
So, there’s hope for us long sleepers after all. Dr. Fu says, “we hope to learn what makes for a good night’s sleep, so that all of us can be better sleepers leading happier, healthier lives.”