Recent advances in sleep genetics

Abstract

Sleep regulation has a strong genetic component. In this review, we highlight the recent advances in sleep genetics from knockout, point mutation, and GWAS studies. We overview specific genetic effects on REM versus NREM sleep as well as how the implicated genes fall in broad functional categories. Furthermore, we elucidate how genes affect different aspects of sleep including sleep duration, sleep consolidation, recovery sleep, and the circadian timing of sleep, demonstrating that genetic studies can be powerful in understanding how the body regulates sleep.

Fig. 1.. Recent genes known to affect sleep by functional category.

Genes affecting sleep fall into many broad functional categories, reflecting that a wide array of biological processes may influence sleep. The bracketed numbers reflect reference the gene is mentioned in. The largest categories are brain-specific genes such as ion channels, neurotransmitter receptors, neuropeptides, and synaptic proteins. However, an increasing number of transcription factors, kinases, metabolism, and cell-signaling factors have also been implicated.

Fig. 2.. Genes can affect specific components of sleep.

Most genes implicated in sleep affect a specific component of sleep, reflecting the fact that these different sleep components are likely regulated by different mechanisms. However, a single gene can sometimes affect multiple components. Sleep duration refers to the average time spent asleep per night. Genes can affect the duration of both REM and NREM sleep. Sleep stability refers to how fragmented or consolidated an organism’s sleep is. Some genes affect the ability of an organism to have consolidated sleep. Circadian timing of sleep refers to when in the circadian day most of an organism’s sleep occurs. Some genes change when in the day the majority of sleep occurs. Finally, some genes affect sleep homeostasis. Genes that affect this component lead to alterations in an organism’s ability to respond to sleep deprivation.