insomniaA research team have discovered seven risk genes for insomnia, taking them one step closer to overcoming the most frequently complained about problem in general practice.

The team led by Vrije Universiteit Professor Danielle Posthuma picked apart the biological mechanisms that cause the predisposition for insomnia, Sci News writes.  

“Our findings are the start of a path towards an understanding of insomnia at the level of communication within and between neurons, and thus towards new ways of treatment,” explained Vrije Universiteit Professor Van Someren, co-author of the study.

“As compared to the severity, prevalence and risks of insomnia, only few studies targeted its causes. Insomnia is all too often dismissed as being ‘all in your head.’ Our research brings a new perspective. Insomnia is also in the genes.”

To locate the genetic factors, the team performed a genome-wide association study and a genome-wide gene-based association study in 113,006 individuals.

The authors continued, “These genes play a role in the regulation of transcription, the process where DNA is read in order to make an RNA copy of it, and exocytosis, the release of molecules by cells in order to communicate with their environment.

“One of the identified genes, MEIS1, has previously been related to two other sleep disorders: periodic limb movements of sleep (PLMS) and restless legs syndrome (RLS). Variants in the MEIS1 gene seem to contribute to all three disorders.

“Strikingly, PLMS and RLS are characterised by restless movement and sensation, respectively, whereas insomnia is characterised mainly by a restless stream of consciousness.”

As well as the seven genes found, they also discovered a genetic overlap with other traits, including anxiety, depression and neuroticism, and low subjective well-being.

First author of the study, Anke Hammerschlag, PhD student at Vrije Universiteit, added, “This is an interesting finding because the characteristics tend to go hand in hand with insomnia. We now know that this is partly due to the shared genetic basis.”

The researchers also studied whether the same genetic variants were important for men and women.

Professor Posthuma, concluded, “Part of the genetic variants turned out to be different. This suggests that, for some part, different biological mechanisms may lead to insomnia in men and women.

“We also found a difference between men and women in terms of prevalence: in the sample we studied, including mainly older than fifty years, 33% of the women reported to suffer from insomnia. For men, this was 24%.”