Medically reviewed by
Dacelin St Martin, MD
Triple board-certified in Sleep Medicine,
Internal Medicine, and Pediatrics.
Understanding Genetics and Sleep Regulation | Genetic Testing For Sleep Disorders? | What’s the Takeaway?
Overview
Sleep is a fundamental physiological activity critical to everyone’s health and well-being.
While a good night’s sleep rejuvenates the body and mind, sleep disorders can upset this delicate balance, resulting in many negative physical and mental health impacts.
Given the significance of sleep to our health, it is essential to comprehend the underlying genetic variables contributing to sleep disorders’ development.
This article will explore the role of genetics in sleep disorders and how understanding these genetic factors can pave the way for more effective treatments and personalized interventions.
Understanding Genetics and Sleep Regulation
Sleep is regulated by a complex interplay of various neurotransmitters, hormones, and neuronal pathways within the brain.
One key regulator of sleep-wake cycles is the circadian rhythm, which follows an approximately 24-hour cycle and influences our daily patterns of sleepiness and alertness.[1]
Circadian rhythms are governed by an internal timing system regulated at the transcriptional level, resulting in 24-hour oscillating gene networks.
Within these networks are circadian genes that regulate physiological and behavioral rhythms.[2] Studies reveal that genetic variations can impact the expression and functioning of these circadian genes.
Specific genes, such as CLOCK, PER, and CRY, have been identified as crucial in regulating circadian rhythms.[3]
Mutations or variations in these genes can lead to circadian rhythm sleep disorders, where individuals experience difficulties in falling asleep or staying awake at appropriate times.
Furthermore, family studies (research that examines whether a specific trait runs in families) indicate that these genetic variations that lead to sleep dysfunction are inheritable.[4]
Numerous sleep problems, such as insomnia, obstructive sleep apnea (OSA), and restless legs syndrome (RLS), have been shown to have a genetic component, according to research conducted on families.[5,6,7]
Also, twin studies have uncovered evidence of a genetic influence on many sleep characteristics like sleep duration and quality.[8]
Recently, experts have turned to unbiased methods, such as genome-wide association studies (GWAS), to identify genetic variants in novel genes implicated in these diseases.[4,9]
These studies provide potent evidence supporting the role of a genetic variant in a disorder by comparing the genome-wide genetic variation among individuals.
For instance, extensive genome-wide association studies (GWAS) have found between 57 and 248 genetic links between insomnia and sleep characteristics such as sleep quality, length, and time.[10] GWAS looks at thousands of people’s genes and helps scientists determine how much each person’s genes affect a specific trait.
Genetic Testing For Sleep Disorders?
Although genetics will undoubtedly play a more prominent role in assessing and treating sleep problems in the future, this is not the case right now.
Medical professionals do not routinely perform clinical genetic testing for sleep disorders. Instead, they use criteria from the International Classification of Sleep Disorders to diagnose sleep problems.
Individuals interested in sleep genetic testing can enroll in a research project or seek DNA testing via consumer firms.
Meanwhile, genetic testing has shown promise as a tool for understanding the genetic basis of various sleep-related conditions. Here are some ways in which genetic testing can be beneficial for sleep disorders:
● Risk Assessment: Genetic testing can assist in identifying specific genetic mutations or variants associated with particular sleep disorders. For instance, specific genetic markers have been associated with narcolepsy, a neurological disorder typified by excessive daytime lethargy and an abrupt loss of muscle tone (cataplexy).[11] By analyzing a patient’s DNA, medical experts can now assess a patient’s risk of getting narcolepsy and other sleep disorders.
● Personalized and Precision Treatment: Many sleep disorders necessitate unique treatment approaches. Genetic testing aids in identifying the optimal treatment approach for an individual by analyzing their genetic composition. For example, genetic variations can impact the metabolism of insomnia medications. Preemptive knowledge of this information can assist healthcare providers in customizing medication type and dosage based on their patient’s genetic profiles, thereby improving treatment outcomes.
● Family Screening: Like many other health conditions, sleep disorders can run in families due to shared genetic factors. Identifying genetic mutations related to sleep disorders in one family member may prompt screening and early intervention for other at-risk family members, even if they haven’t shown symptoms yet. This proactive approach can improve treatment outcomes for conditions with a genetic predisposition, such as restless leg syndrome or sleepwalking disorders.
● Research and Advancements: By studying the genetic basis of sleep disorders through large-scale genetic testing, researchers can better understand the biological pathways and mechanisms involved in these conditions. This knowledge can lead to new treatment modalities and therapies targeting specific genetic factors.
What’s the Takeaway?
It’s crucial to note that sleep health is a multifaceted issue, and genetics is just one piece of the puzzle.
Environmental factors, lifestyle choices, and other health conditions also play essential roles in determining the quality of one’s sleep and the outcome of sleep disorders.
By optimizing your sleep environment and embracing healthy lifestyle choices, you can substantively improve your sleep and, ultimately, your physical and mental health.
References
- Reddy, S., Reddy, V., & Sharma, S. (2023). Physiology, circadian rhythm. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK519507/
- Rijo-Ferreira, F., & Takahashi, J. S. (2019). Genomics of circadian rhythms in health and disease. Genome Medicine, 11(1). https://doi.org/10.1186/s13073-019-0704-0
- Charrier, A., Olliac, B., Roubertoux, P., & Tordjman, S. (2017). Clock Genes and Altered Sleep-Wake Rhythms: Their Role in the Development of Psychiatric Disorders. International journal of molecular sciences, 18(5), 938. https://doi.org/10.3390/ijms18050938
- Parsons, M. J. (2015). On the genetics of sleep disorders: genome-wide association studies and beyond. Advances in Genomics and Genetics, 5, 293–303. https://doi.org/10.2147/AGG.S57139
- Beaulieu-Bonneau, S., LeBlanc, M., Mérette, C., Dauvilliers, Y., & Morin, C. M. (2007). Family history of insomnia in a population-based sample. Sleep, 30(12), 1739–1745. https://doi.org/10.1093/sleep/30.12.1739
- Winkelmann, J., Wetter, T. C., Collado-Seidel, V., Gasser, T., Dichgans, M., Yassouridis, A., & Trenkwalder, C. (2000). Clinical characteristics and frequency of the hereditary restless legs syndrome in a population of 300 patients. Sleep, 23(5), 597–602. https://pubmed.ncbi.nlm.nih.gov/10947027/
- Mathur, R., & Douglas, N. J. (1995). Family studies in patients with the sleep apnea-hypopnea syndrome. Annals of internal medicine, 122(3), 174–178. https://doi.org/10.7326/0003-4819-122-3-199502010-00003
- Barclay, N. L., & Gregory, A. M. (2013). Quantitative genetic research on sleep: a review of normal sleep, sleep disturbances and associated emotional, behavioural, and health-related difficulties. Sleep medicine reviews, 17(1), 29–40. https://doi.org/10.1016/j.smrv.2012.01.008
- Raizen, D. M., & Wu, M. N. (2011). Genome-wide association studies of sleep disorders. Chest, 139(2), 446–452. https://doi.org/10.1378/chest.10-1313
- Byrne E. M. (2019). The relationship between insomnia and complex diseases-insights from genetic data. Genome medicine, 11(1), 57. https://doi.org/10.1186/s13073-019-0668-0
- Mignot E. (1998). Genetic and familial aspects of narcolepsy. Neurology, 50(2 Suppl 1), S16–S22. https://doi.org/10.1212/wnl.50.2_suppl_1.s16
