At least a third of American adults report getting less than the seven-plus recommended hours of shut-eye per night, according to the Atlanta-based Centers for Disease Control and Prevention. And recent studies have shown about 25 percent of Americans experience acute insomnia annually.
Now, new research from the Netherlands suggests there may be some genetics behind the sleep disorder.
The study, recently published in the journal Nature Genetics, features genetic and sleep data on 1,331,010 individuals. The dataset, the largest of its kind on insomnia, came from the United Kingdom Biobank and DNA testing company 23AndMe.
In their analyses, researchers found 202 genetic loci (including areas of the brain) and 956 risk genes for insomnia, but it’s the combined effect of these genes that researchers believe is most interesting. In the study, scientists noted “considerable genetic correlations with psychiatric traits and sleep duration, and modest correlations with other sleep-related traits.”
What that means is that folks with insomnia had more risk genes in common with psychiatric issues like depression and anxiety than they had in common with other characteristics related to sleep, such as being a “night owl” or “morning lark,” Medical News Today reported Tuesday.
Further analyses, the site added, “revealed that some of these genes were key to the functioning of axons, or extensions of nerve cells that facilitate electrical communication with other neurons.”
“It looks as if people who have the risk genes have trouble getting rid of tension during sleep,” neurophysiologist and co-author Eus Van Someren of the Netherlands Institute for Neuroscience told Dutch broadcaster NOS. “Often insomniacs will be told to relax and stop moaning. But we think some people are more prone to insomnia than other(s) and we want to know why,” he added.
“We have always searched for causes of insomnia in the brain circuits that regulate sleep,” Someren said in a separate statement to Medical News Today. “We have to shift our attention to the circuits that regulate emotion, stress, and tension. Our first results in that direction are already spectacular.”
The Dutch scientists said the new findings “highlight key brain areas and cell types implicated in insomnia, and provide new treatment targets.”
The next step, researcher Guus Smit of the Vrije Universiteit Amsterdam said, is to “start searching for underlying mechanisms in individual brain cells” and develop ways to combat the sleep disorder.