Insomnia, a common sleep disorder, affects millions of people worldwide. It disrupts sleep patterns and diminishes the quality of life. Researchers have explored various factors that contribute to insomnia, including environmental, psychological, and genetic influences. This blog delves into the genetic aspects of insomnia, providing insights and examining current research.

What is Insomnia?

Insomnia means having trouble falling asleep, staying asleep, or waking up too early and not being able to go back to sleep. It can lead to daytime fatigue, irritability, and problems with thinking and concentration. Chronic insomnia, which lasts for months or years, often has multiple causes, including genetics.

Related: Insomnia: Meaning, Impact, Causes, and Management

Is Insomnia Genetic?

Recent research suggests that genetics can play a significant role in insomnia. This means that your likelihood of having insomnia could be influenced by your family’s health history.

Twin and Family Studies

Studies on twins have been helpful in understanding how much genetics contribute to insomnia. By comparing identical twins (who share all their genes) with fraternal twins (who share half their genes), researchers found that about one-third of the risk for insomnia comes from genetics.

Family studies also support this genetic link. If you have a close relative with insomnia, you are more likely to experience it yourself. This indicates that insomnia can run in families.

Genetic Research

Genetic studies have identified specific areas in our DNA that are associated with insomnia. For example, a large study involving more than a million people found 202 areas in our genes linked to insomnia. These areas are involved in different biological processes, such as brain function, sleep-wake cycles, and how we respond to stress.

How Genes and Environment Interact

While genetics play an important role, insomnia usually results from a mix of genetic factors and environmental influences. Stress, lifestyle, and medical conditions can trigger or worsen insomnia in people who are genetically predisposed to it.

Genes Affecting Sleep-Wake Cycles

Certain genes control our body’s internal clock, which regulates when we feel sleepy and awake. Variations in these genes can disrupt our sleep patterns. For example, changes in the CLOCK gene have been linked to delayed sleep phase syndrome, where people have trouble falling asleep and waking up at normal times.

Genes Affecting Stress Response

Other genes influence how we respond to stress. Some people have variations in a gene called FKBP5, which affects how our bodies handle stress. These variations can make people more likely to develop insomnia, especially when they are under a lot of stress.

What This Means for Treatment

Understanding the genetic basis of insomnia can help improve treatments. By identifying people with a genetic predisposition to insomnia, healthcare providers can offer personalized treatments. This might include targeted therapies, such as cognitive-behavioral therapy for insomnia (CBT-I) and specific medications that work best for individuals with certain genetic profiles.

Conclusion

Insomnia is a complex disorder with significant genetic components. Twin, family, and genetic studies have highlighted the hereditary nature of insomnia, while gene-environment interactions add to its complexity. Advances in genetic research offer promising avenues for personalized treatments, potentially improving the quality of life for those affected by insomnia.

References

1. Benedetti, F., Radaelli, D., Poletti, S., Locatelli, C., Falini, A., Colombo, C., . . . & Smeraldi, E. (2019). FKBP5 polymorphisms as predictors of PTSD symptoms in subjects exposed to natural disasters. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 180(1), 45-53.
2. Drake, C. L., Friedman, N. P., Wright, K. P., & Roth, T. (2014). Sleep reactivity and insomnia: Genetic and environmental influences. Sleep, 37(9), 1347-1356.
3. Gaggioni, G., Maquet, P., Schmidt, C., Dijk, D. J., & Vandewalle, G. (2014). Neuroimaging, cognition, light and circadian rhythms. Frontiers in Systems Neuroscience, 8, 126.
4. Jansen, P. R., Watanabe, K., Stringer, S., Skene, N., Bryois, J., Hammerschlag, A. R., . . . & Posthuma, D. (2019). Genome-wide analysis of insomnia in 1,331,010 individuals identifies new risk loci and functional pathways. Nature Genetics, 51(3), 394-403.
5. Lind, M. J., Aggen, S. H., Kirkpatrick, R. M., Kendler, K. S., & Amstadter, A. B. (2017). A longitudinal twin study of insomnia symptoms in adults. Sleep, 40(2), zsw039.