Is this why I don't need much sleep?

It appears our genes may answer the question why some of us can skate by on little sleep and why others complain if they get anything less than 8 hours.

clipped from www.newscientist.com How well people perform on tests after being deprived of sleep depends in part on their genes, new research suggests. After staying awake all night, individuals with a long version of the PER3 gene only scored half as well on cognitive tests as subjects with a short version. What is more, the greatest differences in performance were seen during the small hours – the time when most tiredness-related accidents happen and when shift-workers have most trouble staying awake. The recordings revealed that although both groups slept for about the same amount of time, subjects with the short PER3 gene spent roughly 15% of this time in deep sleep, also known as slow-wave sleep. Their counterparts with the long PER3, meanwhile, spent about 22% in this restorative sleep stage. So even though people with the long form of PER3 normally get more deep sleep, they actually perform worse on cognitive tests when deprived of sleep. The findings suggest some people need more deep sleep than others.