In a modern world filled with blinking lights and flashing screens, sleep is becoming a rare commodity. So much so that as much as a third of the US adult population isn’t getting the recommended amount of shut-eye each night.
Yet for a small percentage of the population, this isn’t much of a problem. They have a hidden superpower. And many of them don’t even know it.
Believe it or not, somewhere between 1 and 3 per cent of the population don’t need eight hours like the rest of us normies.
‘Short sleepers’, as they’re known, can function just as well as the rest of us on a consistent four to six hours.
And here’s the part that lifts the eyebrow: scientists are starting to understand why. More importantly, they’re beginning to wonder whether the rest of us could one day share that ability.
In other words, sleeping just four hours a night might, at some point, genuinely be all you need.
Who are these hidden superheroes?
Natural short sleep isn’t a mindset, a habit or a product of willpower. It’s a biological variant.
Over the past two decades, researchers have identified a small cluster of genes that allow some people to sleep far less than average while remaining perfectly healthy.
One of the first clues came from a gene called DEC2, which helps regulate levels of orexin, a brain chemical that promotes wakefulness.
Too little orexin is known to cause narcolepsy; yet natural short sleepers appear to produce more of it, keeping them alert on much less rest.
When researchers introduced the mutation into mice, they found the animals slept significantly less without showing the cognitive lapses that normally follow sleep deprivation.
Since then, at least seven genes have been linked to this phenomenon. In every case, engineering the human mutation into mice leads to the same result: shorter sleep cycles with no obvious downside.
According to Prof Guy Leschziner, a consultant neurologist and sleep expert, everything we currently know suggests that natural short sleep is entirely genetic.
He rarely sees such people in clinic – partly because it isn’t a disorder, and partly because those who have it often don’t realise they’re unusual.
“Short sleepers don’t assume it’s abnormal in any way until someone close to them points it out,” he says.
“Particularly if there’s a family history, there will be other individuals who sleep with a similar pattern. So for them it’s normal.”
But while natural short sleepers remain a genetic rarity, the science that explains them is accelerating.
And that opens up a radical possibility: instead of waiting for nature to hand out the short-sleep lottery ticket, could we one day engineer it?
Read more:
- What happens in my body when I don’t get enough sleep?
- How hidden ’overtiredness’ is ruining your sleep – and how to fix it
- Here’s what your nationality says about your sleep needs
Enter CRISPR
CRISPR is a gene-editing technology that allows scientists to change DNA with remarkable precision. Originally part of a bacterial defence system, it has become one of the most powerful tools in modern biology.
The key components are enzymes, which can act like programmable scissors.
By giving these enzymes a short genetic address, scientists can tell them exactly where to cut in the genome. Once cut, the cell’s repair processes can be redirected to delete a gene, fix a mutation or insert new DNA.
So far, CRISPR has mostly been used to treat genetic diseases such as sickle cell disease. But as the technology improves, many researchers believe it could move beyond treating illness to enhancing human abilities – including, potentially, sleep.
Speaking at GITEX Global in October, Dr Trevor Martin, CEO of the genetic engineering company Mammoth Biosciences, told the audience: “Did you know that there’s a percentage of the population that only needs three or four hours of sleep a night?
“And they’re not tired, they don’t just tough it out, they genuinely only need three hours of sleep. People talk about longevity a lot, but imagine if we could all have that… From a technology perspective, these things are possible.”
His company is developing new CRISPR tools that are smaller and easier to deliver into human cells than previous attempts.
“Our mission is to eliminate genetic disease,” he tells BBC Science Focus. “We’re building CRISPR technologies that can make any type of edit in any cell in the body.”
For now, Mammoth is focusing on rare genetic disorders like familial chylomicronemia syndrome and severe hypertriglyceridaemia.
But Martin is candid when he talks about where this technology is going: “There’s no reason that you have to stop there.”
But how easy would it actually be to edit someone into a short sleeper? According to Leschziner, it is definitely theoretically possible, but it won’t be straightforward.
“In theory, if you could identify all of those genes that give a contribution, then of course you could modify people’s genetic makeup,” he says.
“But it’s not quite as straightforward as simply taking one gene out or introducing a mutation into one gene.”
There’s also the societal question. “I guess there would need to be some sort of reconfiguration of society, as we would all have an extra three or four hours in our day to fill,” Leschziner says.
“The question is whether or not that will be filled by work or pleasure. I don’t know.”
A ‘one-and-done’ upgrade
At this point, you might be concerned that if such a treatment were developed in the coming years, only a select few might have access to it.
But Martin argues that, thankfully, they wouldn’t be limited to elites.
“I think the good news on the genetic medicine side that’s underappreciated is that the nature of the technology is that it’s a one-and-done,” he says.
“You don’t have to take a drug for the rest of your life. You come into the doctor’s office once. Yes, we can talk about pricing, but fundamentally, it doesn’t require massive healthcare infrastructure around the person for the rest of their life.”
For now, editing someone into a short sleeper remains firmly speculative. But the science of sleep efficiency is advancing quickly, and CRISPR is maturing even faster.
For the first time, researchers can say – with a straight face – that unlocking an extra three or four waking hours each day might genuinely be possible.
It won’t be today or tomorrow. But one day soon, four hours of sleep really will be all you need.
Read more:
- 8 science-backed secrets to a more restful night’s sleep
- Keeping your eyes open can help you fall asleep faster. Here’s why
- Always tired? A fixed bedtime matters more than sleep duration, study finds
