Scientists believe they have identified the gene which determines how much sleep humans can get by on.
Humans get by on between six to 12 hours sleep a night
A US team found that fruit flies with a mutated version of the gene were able to get by on much less sleep than others.
Fruit flies have a similar genetic make-up and sleep patterns to humans.
University of Wisconsin Medical School researchers said the findings might help develop new techniques to treat people with sleeping problems.
Fruit flies sleep anywhere between six and 12 hours each night - just as humans do.
But in the study of 9,000 flies, published in the journal Nature, the researchers found some were functioning on just three or four.
The flies which could get by on less sleep had a fault in a gene called Shaker, which stopped the flow of potassium into cells.
However, one consequence of their sleeping patterns was that they died much earlier.
Recent studies have suggested potassium may be involved in sleep patterns in humans.
Much is already known about the timing of sleep, which is regulated by the circadian system, but the team said this research would help understand how sleep was controlled, which could in turn benefit humans.
Lead author Dr Chiara Cirelli said: "The more behaviours we look at in terms of sleep, the more we find that sleep in fruit flies is very, very similar to sleep in mammals.
"Humans have the same kind of genes and potassium channels.
"The research offers the possibility of developing a new class of compounds that could affect potassium channels in the brain rather than other brain chemical systems targeted currently."
Sleep expert Dr Simon Archer, of the University of Surrey, UK, said: "As humans have the same gene, it is certainly possible it will act in the same way as it has for fruit flies.
"But we cannot assume that. Fruit flies and humans are quite different so we need more research."
He said if the results were replicated it opened up the possibility of predicting which people would suffer from not being able to sleep when they got older and helping them at an early stage.
And he added: "Gene therapy could also be used to reverse this, although I am not sure we are at the stage where we would want to see that happen."