Humans, like most animals, need their beauty sleep. But the preferred amount and quality of sleep vary between individuals—and some individuals exhibit a heritable, lifetime tendency to sleep less then 6 hours per night. He et al. (see the Perspective by Hor and Tafti) identified a mutation in humans associated with people who regularly require shorter-than-usual sleep duration. The mutation is found in the gene encoding a transcriptional repressor, DEC2, already implicated in regulation of circadian rhythms. Related mutations introduced into mice and flies similarly resulted in shortened sleep phases.
Y. He, C. R. Jones, N. Fujiki, Y. Xu, B. Guo, J. L. Holder Jr., M. J. Rossner, S. Nishino, Y.-H. Fu, The transcriptional repressor DEC2 regulates sleep length in mammals. Science 325, 866–870 (2009). [Abstract] [Full Text]