Sleep - How Much?

How much sleep you need could be down to one gene, claim scientists

Margaret Thatcher, who famously got by with just four hours sleep a night as Prime Minister, may carry a special 'awake' gene as scientists find some people are genetically programmed to survive on less than six hours a night.

By Richard Alleyne, Science Correspondent
Published: 7:00AM BST 14 Aug 2009

Researchers have identified a gene mutation that appears to be at least partly responsible for the fact that the people carrying it require a few hours less sleep than the usual eight.

Researchers have identified a gene mutation partly responsible for the fact that the 

people carrying it require a few hours less sleep than the usual eight Photo: Saalik Siddikki

However the mutation itself is believed to be quite rare.

Ying He and colleagues at the University of California studied an extended family in which a mother and daughter regularly sleep for an average of roughly six hours a night while the other members needed more than eight.

They found that a variant gene was shared by the mother and daughter but not their relatives.

The researchers next compared the sleep cycles and brain activity of mice modified to carry the gene and normal mice.

The genetically modified mice not only slept less, with more frequent periods of wakefulness, they also needed less time to recover from a period of sleep deprivation. Related mutations in fruit flies also led to shortened sleep phases. The authors, who published their findings in Science, said the genes could offer a useful new model for studying human sleep.

Source : http://www.telegraph.co.uk/science/6022543/How-much-sleep-you-need-could-be-down-to-one-gene-claim-scientists.html