Do you have the gene for a good night's sleep?

Everyone loves catching some ZZZs. For some of us, sleep is not always restful, and for scientists, it’s still a bit of a mystery as to why we even need it and the long-term effect disrupted sleep can have on the body. But researchers at Washington State University (WSU) are one step closer to the answer and have uncovered a gene linked to whether you will have a good night’s sleep or not.

The gene in question is fatty acid binding protein 7, or FABP7 for short. Jason Gerstner, the author of the study, found that those with the normal version of the gene had a better night’s sleep than those with a mutated or altered form of FABP7. What sets this study apart is that this is the first time this observation has been made across multiple animal species.

The WSU team first looked into the sleep cycle of mice and added either the mutated or normal form of FABP7 to star-shaped cells found in the brain called astrocytes. Previously, it was thought that these cells were mainly used to support neurons, the brain cells that process information. But it appears that astrocytes also play a role in controlling behaviour.   

Mice lacking the FABP7 gene (also known as “knockout mice” because the gene has been “knocked out”) also had more disrupted sleep than animals with a working copy of the gene.

Next, Gerstner and the team studied this gene in 300 human males. Genetic analysis showed that 29 of them naturally carried the mutated version of FABP7. Using a digital wrist strap, much like a watch, the team were able to monitor rest-wake activity in these individuals over the course of a week. Just like the mice, those with a mutated FABP7 gene slept more fitfully. The same relation was also found in fruit flies.

But why is this corresponding result across different species important? This is the first study of its kind to find this same pattern across different members of the animal kingdom and will lead to further investigations between sleep and our ability to learn and retain memories. 

“As a means of understanding what sleep is doing in humans, it’s critical to find similar systems that occur throughout the animal kingdom. Finding this across humans, mice and flies is important as it helps us determine the function of sleep,” says Gerstner.

Why we sleep and the long-term effects of disrupted sleep are still unknown. Gerstner will now look to explore whether the mutated and normal version of FABP7 plays a role our brain’s ability to processes information, especially with common diseases such as dementia. According to Alzheimer’s Society, there are an estimated 35.6 million people across the world already living with the disease. This latest discovery opens new studies into our brain’s function, and the effect disrupted sleep can have on learning ability, long-term memory and brain ageing.