awake at dawn short sleep gene
An inherited gene mutation that lets you sleep less, and has a range of health benefits... Image Credit: Unsplash/Sage friedman

What if you could wake up after four hours of night sleep feeling completely refreshed, your mind clear and active? You’re springy and energetic in the quiet hours of dawn, where the only sounds are of gently chirping birds. Almost 20 hours of your day await, and the possibilities are endless.

What’s more - it’s like this every day, for the rest of your life.

If you relate to that, you’re in luck! In science, you would be a ‘familial natural short sleeper’ (FNSS) or someone having the ‘short sleep syndrome’ – an inherited gene mutation that genetically programs you to sleep less and get by with only four to six hours of shut-eye.

Not only do you have more time, but there are range of health benefits for this genetic lottery prize too! We speak to Dr Syed Arshad Husain, consultant pulmonologist at Dubai-based King’s College Hospital’s sleep medicine clinic to find out more.

Normal sleep deprivation vs when you’re a ‘short sleeper’

Woman tired sleep at desk work short sleep
Normally, when people get only six hours of shut eye, we are groggy throughout the day - but not short sleepers. Image Credit: Pexels/Rodnae Productions

“Usually, people require seven to eight hours of sleep to have a fresh, healthy start in the morning. If people have sleep deprivation, then they may have obesity, their weight increases – they may have diabetes, they have high blood pressure, which causes cardiovascular problems and increased risk of stroke and heart attacks,” explains Dr Husain.

“People who are sleep deprived that we see in our clinics, mostly sleep apnea – they are not performing well on their job, their concentration span is lost, they get sleepy in the daytime, they nap or doze off. With sleep deprivation and obstructive sleep apnoea, people can have memory deficits, and there is a higher mortality in this group.”

If people have sleep deprivation, then they may have obesity, their weight increases – they may have diabetes, they have high blood pressure, which causes cardiovascular problems and increased risk of stroke and heart attacks.

- Dr Syed Arshad Husain, consultant pulmonologist at Dubai-based King’s College Hospital’s sleep medicine clinic

All of this, including the risk for diseases, disappears when you have the ‘short sleep’ gene – you can gleefully go about your day with zero side effects, lifelong.

Research into this began back in 2009, when Ying-Hui Fu, a biologist and human geneticist at the University of California San Francisco (UCSF), had come across a curious case – a woman who told her she always woke up strangely early but refreshed, as did another member of her family. In a groundbreaking study published that year in the journal Science, Fu and the team at UCSF found, after sequencing the DNA of the family, that they had a mutation in the gene DEC2, BHLHE41 that caused this oddity.

Dr Husain says, “It is an eye opener, we always thought that you need a decent amount of time to sleep to be refreshed but these genetic studies prove that in a lesser amount of time you can still have effective working capacity and good health – sleep quality over duration.

“In the families, where the DEC2 gene was present, they were having like 4.2 to 6.2 hours of sleep but they performed well. They did not develop dementia, or memory deficits, which happens when you're sleep deprived, and they are probably going to live longer.”

The researchers had bred mice genetically engineered with the gene for the studies, to prove this.

Multitasking, but make it extreme

productivity short sleeper multitasking
Short sleepers are not only high-energy and productive, they even hold multiple jobs happily with all the time on their hands! Image Credit: Shutterstock

If you thought all that was already unfairly advantageous – there’s actually more! The researchers said in a 2020 study published in Neuropsychopharmacology, the official publication of the American College of Neuropsychopharmacology: “It is not just sleep duration that characterises this group of individuals. There is a high behavioural drive among those with FNSS, and individuals report a need to always be mentally active resulting commonly in high profile, high pressure jobs or holding multiple jobs. FNSS individuals also appear to have high pain thresholds and relative resilience to life stressors.”

In a 2011 article on the National Public Radio (NPR) website, Fu also recounted her experience working with them: “A lot of them are very energetic; they are multitaskers. They have two or three jobs, and they feel great.” She has also described them as optimistic.

Some other benefits are –

• May have less risk of dementia – In March, 2022, a new study published in the journal iScience, peer-reviewed academic journal of the American Association for the advancement of science showed that two ‘short sleep’ genes reduced the development of ‘tau’ tangles or abnormal clumps of amyloid plaques in the brain – both of which are associated with neurodegenation, dementia and Alzheimer’s.

• No memory deficits – A 2019 study with mice in the journal Science Translational Medicine by the UCSF researchers showed that the animals were resistant to any cognitive impairment by less sleep.

So, what is the enigma behind this impossibly good trump card?

So far, 3 genes unlock this

Sleep family with parents and two kids
This gene mutation is very rare, but is inherited - which means beside you on your 4 am run will be your sibling or parent. Image Credit: Pexels/Ketut Subiyanto

“The incidence of this gene mutation is very, very rare, less than 1 in 4 million population. There are different mutations that have been found in the families and their genetics, and one of them is called DEC2, then ADRP1 and another one, NSPR1,” says Dr Husain.

How do they really optimise our sleep?

Altering our circadian rhythms - According to a 2014 study by the University of Pittsburgh published in the journal Sleep, our circadian (sleep-wake cycle) rhythms depend on certain ‘master’ genes CLOCK and BMAL1 and the short sleep mutations can alter its activation.

Easier-to-wake brains – The dorsal pons is the area in our brain that regulates sleep. 10 years after the first discovery, the UCSF researchers not only found a second gene, but that the neurons there responsible for waking us up were more easily activated or ‘excitable’ when they had this mutation. They also stayed awake longer. This was a study published in Neuron journal.

However, Dr Husain explains that how the ‘short sleep’ genes exactly work in the brain is not yet fully understood and remains an area of intense research.

This could mean a future where less sleep is not a problem

Only got 4 hours of sleep? Maybe in the future, we'll be just fine with that much. Image Credit: Pexels/Cottonbro

One day, we may know the secret to the most efficient, quality sleep thanks to these genes. Or be able to prevent disorders and diseases from chronic sleep deprivation that plague many of us today.

Dr Husain says, “A lot is not known about this gene mutation as it's a very rare condition.

“This is all for scientists to work on and maybe develop some genetic engineering treatment or gene therapy that will be given to patients to have a shorter but very effective sleep, and then perform very well and have none of these problems that I've talked about. No obesity, no blood pressure, no strokes, no related deaths.”