A recent study, published in the scientific journal Nature Genetics, has found the genetic roots of insomnia and discovered the complex genes linked to this condition.
The research team then dug even deeper, using a new technique which managed to get how this mosaic of genes help to code for specific cell types which make up different parts of the brain. These findings could lead to treatments which might help people around the world struggling with insomnia.
Insomnia is amongst the most common health conditions in the world, affecting around 770 million people across the world. It is a sleep disorder which is characterized by trouble falling or staying asleep.
People with this condition have one or more of the following symptoms; like they may have difficulty falling asleep. Waking up during the night and then having difficulty going back to sleep again.
Findings of the study
Previously, it’s been proposed that insomnia has a genetic factor and strongly runs through families. But the several genes and brain cells behind this have never been evidently recognized until now.
An international team of researchers has investigated the genetic data of around 1.3 million individuals. They identified 956 gene variants which are linked to an increased risk of insomnia. They also revealed that some of these genes play a central role in the working of axons.
Axons are the long “wire” projections which conduct electrical “messages” away from the cell body of the neuron. Identified genes seemed to exert an effect on specific types of cells, including hypothalamic, striatal, and claustrum neurons.
Other genes were also associated with activity in some parts of the brain formerly suggested to be associated with chronic restless sleep, the frontal cortex and the subcortical nuclei.
The researchers also compared risk genes of insomnia with those of other disorders and traits. Amazingly, they found a slight overlap with genes involved in individual alterations in other sleep traits, such as being a ‘night owl’ or a ‘morning person’.
Notably, the study also highlights a solid genetic resemblance with anxiety and depression. According to the researchers of the study, these discoveries are a revolution, as for the first-time researchers start searching for fundamental mechanisms in individual brain cells in the laboratory.
Specific cell types involved in insomnia
Moreover, this study demonstrates that insomnia, like other neuropsychiatric disorders, is influenced by hundreds of genes, each of small effect.
And these genes by themselves are not that interesting to investigate. What counts is their joint effect on the risk of insomnia. Researchers investigated this with a novel technique, which allowed them to detect specific types of brain cells, as the medium spiny neurons.
To reach these discoveries, the research team used immense banks of genetic data from the UKBiobank and 23andMe, the consumer genomics and biotechnology company.
This method has been used many in genome-wide studies as it provides researchers with a unique amount of valuable data to work with. For instance, similar studies have also found some of the genetic keystones of depression and a variety of inherited situations, like cystic fibrosis.