Sleep well last night? You can thank your genes for that.

Sleep well last night? You can thank your genes for that. According to an experiment by a group of US scientists, a specific gene is necessary to ensure a good night’s sleep, and cases of that gene being mutated or altogether absent are consistently connected to having a fitful sleep. The theory also holds up across different species: The experiment was first run on mice before it was run again on a group of humans and some fruit flies, for good measure. A separate study also found that it’s a whole other gene that determines how much sleep different people need to feel rested, and discovered that a rare mutation actually allows human brains to regenerate in less time (watch, runtime: 3:38).