Let's talk aboutSleep Movement & Genetics

You may be surprised, but twitching doesn’t necessarily mean you’re having nightmares—many factors influence sleep movement, including genetics.

The science of sleep movement

Did you know that many people twitch multiple times throughout the night while they’re asleep? These involuntary twitches are called periodic limb movements, or PLMs. During sleep studies, researchers measure PLMs by placing electrodes on the arms and legs of a sleeping person.

The genetic link

Scientists have identified a genetic marker in the BTBD9 gene that impacts sleep movement. There are two possible versions of this marker: the A variant and the G variant. For each copy of the A variant a person has, they’re likely to move their limbs an additional 4-5 times per hour while sleeping, compared to people with two copies of the G variant.

different amounts of sleep movement

Did you know?

The average person moves about 13 times an hour during sleep. But some people barely budge, and others may move more than 100 times per hour.

Explore more

Ever wondered how much you move in your sleep? 23andMe’s Health + Ancestry kit can tell you more about your own sleep movement. Order a kit and find out how much you’re likely to move in your sleep based on your genetics.

Health + Ancestry Service Kit

Health + Ancestry Service

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