Just one week of abnormal, insufficient sleep is enough to dramatically alter the activity of human genes, according to a new study published by the Proceedings of the National Academy of Sciences.

The research, conducted at the University of Surrey, England, has revealed that insufficient sleep - less than six hours a night - affects the activity of over 700 of our genes.

These genes are associated with controlling response to stress, immunity, and inflammation.

Additionally, the research shows that insufficient sleep decreased the number of genes that normally peak and fall in expression during a 24-hour period from 1,855 to 1,481.

The investigators discovered that the number of genes influenced by sleep deprivation was seven times greater after a week of poor sleep.

Not enough sleep can result in many health complications such as: Sleep disorders are common. According to the Centers for Disease Control and Prevention, USA, sleep deprivation and sleep disorders affect from 50 to 70 million people in America.

Sleep Deprivation And Disorders Affect 50 To 70 Million Americans Until recently, scientists were unaware how gene expression patterns were modified by poor sleep. These 'gene expression' patterns offer critical clues on the possible molecular mechanisms that connect sleep with total health.

The researchers followed 26 volunteers who were exposed to one week of inadequate sleep and then one week of sufficient sleep. After each week, blood samples were taken and were controlled for the effects of light, activity, and food during the week of insufficient sleep.

The genes affected by poor sleep were linked to circadian rhythms, metabolism, and sleep homeostasis.

The biological processes that the investigators found as being affected were:
  • macromolecular metabolism
  • gene-expression regulation
  • chromatin modification
  • inflammatory responses
  • immune responses
  • stress responses
Derk-Jan Dijk, Director of the Sleep Research Centre at the University of Surrey commented:

"This research has helped us to understand the effects of insufficient sleep on gene expression.  Now that we have identified these effects we can use this information to further investigate the links between gene expression and overall health."

This study was carried out by a collaborating team of researchers consisting of sleep and circadian rhythm experts in functional bioinformatics and genomics, as well as physiologists.

The biological processes identified may be involved with the negative outcomes of poor sleep on health and emphasize the links between sleep homeostasis, circadian rhythmicity, and metabolism.

Colin Smith, Professor of functional genomics at the University of Surrey says:

"The current interest in sleep and circadian rhythms as determinants of health and disease is a vital area of research.  By combining our expertise in sleep and 'genomics' (the study of the full complement of our genes), we are starting to make breakthroughs that will have an impact on our understanding and treatment of poor health arising from insufficient sleep."

Written by Kelly Fitzgerald