People with ‘elite sleeper’ genes, which see them need only four to six hours of sleep a night, may also have some protection against neurodegenerative disease.
A new study into Familial Natural Short Sleep (FNSS) – the ability to function fully on, and have a preference for, shorter amounts of sleep each night – shows this can run in families.
To date, the team at UC San Francisco have identified five genes across the genome that play a role in enabling this efficient sleep, although the researchers believe there are many more FNSS genes to find.
And with the ability to thrive on limited levels of sleep can come psychological resilience and resistance to neurodegenerative conditions, which may play a role in fending off neurological disease.
Dr Ying Hui Fu and Dr Louis Ptacek
“There’s a dogma in the field that everyone needs eight hours of sleep, but our work to date confirms that the amount of sleep people need differs based on genetics,” said neurologist Dr Louis Ptacek, one of the senior authors on the study.
“Think of it as analogous to height; there’s no perfect amount of height, each person is different. We’ve shown that the case is similar for sleep.”
For over a decade, Ptacek and co-senior author, Dr Ying-Hui Fu, both members of the UCSF Weill Institute for Neurosciences, have been studying FNSS.
This study tested Dr Fu’s hypothesis that elite sleep can be a shield against neurodegenerative disease.
Her ideas contrast somewhat with current thinking that, for many people, lack of sleep can accelerate neurodegeneration.
The difference, Dr Fu said, is that with FNSS, the brain accomplishes its sleep tasks in a shorter time.
The team chose to look at mouse models of Alzheimer’s disease and bred mice that had both short-sleep gene and genes that predisposed them to Alzheimer’s.
They found that their brains developed much less of the hallmark aggregates associated with dementia.
To confirm their findings, they repeated the experiment using mice with a different short-sleep gene and another dementia gene and saw similar results.
Dr Fu and Dr Ptacek believe that similar investigations of other brain conditions would show the efficient-sleep genes conferring comparable protections.
But in the general population, improving peoples’ sleep could delay progression of disease across a whole spectrum of conditions, they said.
“Sleep problems are common in all diseases of the brain,” said Dr Fu.
“This makes sense because sleep is a complex activity.
“Many parts of your brain have to work together for you to fall asleep and to wake up.
“When these parts of the brain are damaged, it makes it harder to sleep or get quality sleep.”
Understanding the biological underpinnings of sleep regulation could identify drugs that will help ward off problems with sleep disorders, the research team added.
