A gene affecting sleep cycle

Sleep duration and quality can affect many things, including muscle recovery, muscle building, weight loss, athletic performance, learning and cognition. Many gene variants have been reported to affect the sleep cycle or the circadian clock. At FitnessGenes, we test for the Circadian Locomotor Output Cycles Kaput (Clock) gene. Your result tells you whether you do or don't carry any genetic variants associated with a disturbed circadian rhythm and whether you are likely to be a night owl, morning lark or somewhere in between.

Your Circadian rhythm, also known as your body clock, is an internal system that helps synchronize your body with the hours of the sun and regulates feelings of sleepiness and wakefulness over a 24 hour period. The body’s master circadian clock is found in a region of the brain that responds to light. This is why we are alert when the sun is shining and are ready to sleep when it is dark.  A disturbed circadian rhythm can affect appetite, weight loss, learning, memory and physical performance.  Although circadian rhythm can be disturbed by factors including environment, diet and occupation, carrying certain genes can also disturb the circadian rhythm.

You can find more information about the CLOCK gene in our member area at where you can also find your results and what this means for you after your DNA has been analyzed by us. Head over to the shop to order your Fitnessgenes DNA analysis and genetic training system


We have fully reviewed the impact of this gene and the genetic variant we analyse as part of our scientific research process. You can access the full citation list on all studies reviewed here.

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