Can’t sleep? Well, you might be able to blame your genes. Scientists have just confirmed that insomnia is hereditary, identifying certain genetic mutations that they think could lead to the development of the condition. The study is one of the largest of its kind and could help in the hunt for new insomnia treatments.
Insomnia affects around 10-20 percent of adults worldwide and can have a serious impact on a person’s health and wellbeing. In fact, chronic insomnia has been linked to heart disease and type 2 diabetes, along with mental illnesses like post-traumatic stress disorder (PTSD).
Many people assume that insomnia just means you can’t fall asleep at night. However, there are actually various different symptoms, such as waking throughout the night, not being able to fall back to sleep after waking early, and waking in the morning feeling unrefreshed.
Up to half of military veterans experience trouble sleeping, so the researchers behind the new study published in Molecular Psychiatry turned to veterans to collect their data. They conducted genome-wide association studies (GWAS) using the DNA of over 33,000 soldiers participating in the Army Study to Assess Risk and Resilience in Service Members (STARRS) to see how genes are linked to problems with sleep.
The team found that insomnia has a heritable element to it, confirming results of previous studies that have often looked at twins. What’s more, they found that insomnia was connected to certain genetic variations on chromosome 7, and on chromosome 9 in people of European descent. The chromosome 7 variant is found close to a gene involved in alcohol consumption called AUTS2, as well as others connected to brain development and electric signaling linked to sleep.
“Several of these variants rest comfortably among locations and pathways already known to be related to sleep and circadian rhythms,” said lead researcher Murray Stein. “Such insomnia-associated loci may contribute to the genetic risk underlying a range of health conditions including psychiatric disorders and metabolic disease.”
The researchers also found that there was a strong genetic link between insomnia and type 2 diabetes, and that in those of European descent, there’s also a link between insomnia and major depression.
“The genetic correlation between insomnia disorder and other psychiatric disorders, such as major depression, and physical disorders such as type 2 diabetes suggests a shared genetic diathesis for these commonly co-occurring phenotypes,” added Stein.
However, it’s important to note that genetics isn’t the sole root of insomnia, it can also be caused by lifestyle factors like excessive caffeine consumption and working irregular hours as well as certain medications, chronic pain, and various conditions including asthma.
Current insomnia treatments include sleep medicines, cognitive behavioral therapy, and learning how to relax. Finding out more about the genetics of insomnia could help improve current treatments and contribute to finding new ones, as well as identify who is most at risk.