Insomnia may be genetic: study

Scientists have identified specific genes that may trigger the development of sleep problems, and have also found a genetic link between insomnia and psychiatric disorders such as depression, or physical conditions such as type 2 diabetes.

The effects insomnia has on a person's health can be debilitating and place a strain on the healthcare system, according to a study published in the journal Molecular Psychiatry.

Chronic insomnia goes hand in hand with various long-term health issues such as heart disease and type 2 diabetes, as well as mental illness such as post-traumatic stress disorder (PTSD) and suicide.

Twin studies have in the past shown that various sleep-related traits, including insomnia, are heritable, the researchers said.

"A better understanding of the molecular bases for insomnia will be critical for the development of new treatments," said Murray Stein from the University of California, San Diego in the US.

The researchers conducted genome-wide association studies (GWAS). DNA samples obtained from more than 33,000 soldiers were analysed.

Data from soldiers of European, African and Latino descent were grouped separately as part of efforts to identify the influence of specific ancestral lineages.

The researchers also compared their results with those of two recent studies.

The study confirmed that insomnia has a partially heritable basis. They also found a strong genetic link between insomnia and type 2 diabetes.

Among participants of European descent, there was additionally a genetic tie between sleeplessness 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," said Stein.