Can’t manage to get the eight hours of sleep you’re supposed to have each night? A new study suggests your genetics may be to blame.
“Sleep patterns are influenced by genetic differences,” says associate professor of medicine at Harvard Medical School Dr. Daniel Gottlieb. “This study is one of the first to begin identifying these genetic differences, and will hopefully help us better understand the causes of sleep disorders and their relation to other important diseases.”
The study, which appeared on December 2 in the journal Molecular Psychiatry, suggests that certain genetic variations can directly make a difference of a few minutes’ sleep a night. Genetics can indirectly affect sleep, too, the study shows. Scientists believe that several aspects of sleep, including duration, are to some extent inherited. The same gene variations could cause conditions like high blood pressure, which in turn causes sleep problems.
Researchers studied both the genes and sleep habits of 47,180 people of European descent, and of 4,771 African-Americans. They were then able to identify two genetic variations associated with sleep duration, one of which they linked directly to about three minutes of extra sleep a night.
Not only did those with the gene variation sleep a little longer, they also had lower levels of attention-deficit hyperactivity disorder, and lower blood sugar. This means that they were able to be more calm, likely allowing them to go to sleep easier.
The other DNA area that researchers identified, which was linked to shorter amounts of sleep, had previously been associated with psychiatric problems. Variations of it included higher risks for depression and schizophrenia.
All this being said, the differences are tiny at best. The Sleep Research Center’s Jim Horne cautioned against making too much out of the study’s findings.
“There are numerous mechanisms, maybe hundreds, in the brain affecting our sleep one way or another, all of which will be coded by one or more genes,” said Horne. “Those looked at here are just a very few.”
Although the research won’t have an immediate impact on the science of sleep disorders, it could do so one day. Gottlieb explained that the “long-term goal of this research is improved understanding of sleep disorders, including early identification of those at risk for sleep disorders in order to prevent their occurrence.”