Scientists discover that insomnia is in our genes

Millions of us dread bedtime while we go to bed while trying to fall asleep.

But a new study suggesting that insomnia is in our genes gives scientists new hope for healing.

After analyzing the DNA of more than 85,000 people, researchers have discovered 47 genetic sites that determine the ease with which we doze, as well as the length of time we stay awake.

Of these, 36 genes have never been identified before, which could "inform the development of new treatments to improve our sleep".

The study was conducted by the University of Exeter and led by Dr. Samuel Jones, Research Fellow at the Faculty of Medicine and Health.

Dr. Andrew Wood, lead author and speaker in Statistical Genetics, said, "We know that getting enough sleep improves our health and well-being, but we still know enough about the mechanisms in our bodies that influence our sleep.

"Changes in the quality, quantity and rhythm of sleep are strongly associated with several human diseases such as diabetes and obesity, as well as psychiatric disorders."

Identifying the genes at the origin of insomnia "will provide new information on sleep regulation," the authors wrote in the journal Nature Communications.

Although previous studies have found a link between sleep and genetics, they relied on patients who self-reported their symptoms of insomnia.

To improve this, the researchers analyzed 85,670 participants from the British Biobank study who were wearing accelerometers every day for a week. UK Biobank includes the genetic information of half a million people.

These participants were compared to 5,819 people who also wore wrist monitoring devices during other tests.

Accelerometers record our activity levels, which can then be used to indicate sleep patterns.

According to researchers, this is considered a more accurate way of measuring the silence of the eyes than self-reported data.

The results revealed that 47 genetic sites are associated with the duration, quality and timing of sleep.

Of these, 26 sites related to sleep quality and 10 to the duration of our closed eye had never been identified before.

"Sleep quality genes" have been associated with the production of serotonin, a chemical well-being. This neurotransmitter – which transmits chemical messages between nerve cells – has already been associated with deep sleep disorders.

PDE11A is one of the newly discovered genes, which affects both the duration of our sleep and its quality.

PDE11A has already been suggested as a drug target for people with neuropsychiatric disorders affecting mood behaviors or social behaviors.

"This study identifies genetic variants affecting sleep patterns and will provide new insights into the molecular role of sleep in humans," said Dr. Jones.

"This is part of an emerging work that could one day enlighten the development of new treatments to improve our sleep and our overall health."

The results also revealed that those with larger waistlines were less likely to be blinded.

However, this association was very small, with those with a 100 cm hip circumference getting four seconds less sleep per night for each 1 cm increase in waist circumference.

The study also found that those who suffer from restless leg syndrome are less likely to sleep a good night's sleep.