How well we sleep at night may be linked to our genetic coding, according to a new study published in the journal Nature Communications. The researchers identified 47 links between our genetic coding and the quality, quantity and timing of how we sleep; 10 of these links were associated with sleep duration and 26 with sleep quality.
“This study identifies genetic variants influencing sleep traits, and will provide new insights into the molecular role of sleep in humans. It is part of an emerging body of work which could one day inform the development of new treatments to improve our sleep and our overall health,” said lead author Dr. Samuel Jones from the University of Exeter Medical School in the U.K.
For the study, an international team of researchers analyzed the data of 85,670 participants from the UK Biobank and 5,819 individuals from three other studies, all of whom wore accelerometers, wrist-worn devices (similar to a Fitbit) which record activity levels continuously.
The participants wore the accelerometers continuously for seven days, giving more detailed sleep data than previous studies, which have relied on people trying to report their own sleep habits.
The findings include the following:
- Among the genomic regions discovered is a gene known as PDE11A. The research team discovered that an uncommon variant of this gene affects not only how long you sleep but also your quality of sleep. The gene had previously been identified as a possible drug target for treatment of people with neuropsychiatric disorders associated with mood stability and social behaviors;
- Among participants with the same hip circumference, a higher waist circumference resulted in less time sleeping, although the effect was very small — around 4 seconds less sleep per 1 cm waist increase in someone with the average hip circumference of around 100 cm;
- Collectively, the genetic regions linked to sleep quality are also linked to the production of serotonin, a neurotransmitter associated with feelings of happiness and wellbeing. Serotonin is known to play a key role in sleep cycles and is thought to help promote deeper and more restful sleep;
- The group also found further evidence that restless leg syndrome is linked to poorer sleep from the genetic variants they found to be associated with sleep measures derived from the accelerometer data.
“We know that getting enough sleep improves our health and wellbeing, yet we still know relatively little about the mechanisms in our bodies that influence how we sleep,” said senior author Dr. Andrew Wood from the University of Exeter Medical School.
“Changes in sleep quality, quantity and timing are strongly associated with several human diseases such as diabetes and obesity, and psychiatric disorders.”
The team involved researchers from the Center for Sleep and Circadian Neurobiology in Pennsylvania, Massachusetts General Hospital as well as the Netherlands, France and Switzerland.
Source: University of Exeter