Introduction: What Is Snoring?

Snoring is the loud or harsh sound from the nose or mouth that occurs when breathing is partially obstructed. The sound is produced when the soft palate and other soft tissues (such as uvula, tonsils, nasal turbinates, and others) in the upper airway vibrate.

Affecting nearly 90 million Americans, it can lead to disturbed, unrefreshing sleep, ultimately resulting in poor daytime function. Snoring is caused due to obstruction of air passage, resulting in the vibration of respiratory structures and the production of sound during breathing while asleep.

Snoring is more prevalent in males than in females. Certain risk factors such as genetic predisposition, throat weakness, obesity, mispositioned jaw, obstructive sleep apnea, sleep deprivation, alcohol consumption, and mouth breathing are associated with snoring.

How Do Genes Influence Snoring Risk?

Twin and family studies have identified the association between genetic factors and snoring risk, with heritability ranging between 18 to 28%.

A recent study published in 2019 leveraged data from a large U.K. Biobank study consisting of the Australian adult population to identify the molecular mechanisms associated with snoring.

MSRB3 Gene and Snoring

MSRB3 is associated with protein and lipid metabolism pathways, which are related to hippocampal volume (a region in the brain) and lung function. Such genetic associations are consistent with the findings that severe bouts of snoring may be due to:
- Nocturnal oxygen desaturation (temporary drop in oxygen levels in hemoglobin)
- Lowered neuropsychological functions, with reduced ability to consolidate memory.

rs10878269 And Snoring

The rs10878269 is G>A polymorphism located in the MSRB3 gene. A study by Jones, Samuel E., et al.2016 showed that variant rs10878269 was significantly associated with reduced snoring risk.

Non-genetic Influences On Snoring

• Mouth anatomy* : A low, thick, and soft palate can narrow down the airway and may result in snoring
• Nasal problems : Deviated nasal septum and nasal congestion can contribute to snoring.
• Sex : Men are more likely to snore or have sleep apnea than women.
• Obesity : Fatty tissues in the neck of obese/overweight people can narrow the airways and cause snoring.
• Sleep Deprivation : Not getting enough sleep can lead to throat relaxation.

Effects Of Snoring

Snoring is not often considered a serious health concern except in some conditions. Snoring can usually be cured through simple home remedies. Light and infrequent snoring is completely normal. Snoring that is linked to obstructive sleep apnea (OSA) is, however, worrisome and needs to be treated.

Tips For A Snore-free Sleep

1. Reduce the consumption of alcohol and sedatives as this relaxes your muscles and leads to snoring.
2. Maintain your weight as obesity and being overweight are risk factors for snoring and sleep apnea.
3. Change your sleeping position. When you sleep on your back, your airway has higher chances of getting blocked. Sleeping on your side, raising your head by a few inches, or using a pillow to improve your neck position are a few alternative sleep positions to try.
4. Relieve nasal congestion before you sleep.
5. Anti-snoring mouthpieces can be used to hold your jaw and tongue in a suitable position to prevent blockage of the airway,
6. Throat exercises can help strengthen the muscles and prevent them from collapsing during sleep.
7. Try to quit smoking. Smoking can result in inflammation in the upper airway passage, and this blocks airflow.

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Summary

1. Snoring is a common sleep disorder that affects over 90 million Americans. It is characterized by a loud noise from the nose/mouth due to an obstructed airway.
2. Genetic predisposition, throat weakness, obesity, mispositioned jaw, obstructive sleep apnea, sleep deprivation, alcohol consumption, and mouth breathing are some risk factors associated with snoring.
3. The MSRB3 gene, associated with protein and lipid metabolism pathways related to lung function and hippocampal volume, affects sleep-related snoring. The rs10878269 SNP, a G>A polymorphism, is associated with a reduced risk of snoring.
4. Snoring is not a serious health concern unless linked to other sleep disorders like Obstructive Sleep Apnea(OSA).
5. Changing your sleeping position, maintaining a healthy weight, reduced alcohol consumption and smoking, and throat exercises are some of the recommendations to have a snore-free sleep at night.

References

https://pubmed.ncbi.nlm.nih.gov/32060260/

What is Narcolepsy?

Narcolepsy is a sleep disorder that is characterized by five symptoms:
1. Excessive daytime sleepiness
2. Cataplexy (sudden muscle weakness that occurs without any 'warning')
3. Sleep paralysis (a state of awareness with an inability to speak or move - usually occurs during waking up or falling asleep)
4. Hypnagogic hallucinations (vivid dreamlike experiences),
5. Disturbed nocturnal sleep

It affects approximately 1 in 2000 individuals and usually appears during childhood or early puberty.

There are two major types of narcolepsy:
Type 1 narcolepsy (NT1) : It is characterized by excessive daytime sleepiness as well as cataplexy. People with NT1 have lower levels of a brain hormone called hypocretin.

Type 2 narcolepsy (NT2) : Nt2 is a type of narcolepsy without cataplexy. People with NT2 have normal levels of hypocretin.

How Does Genetics Influence the Risk Of Narcolepsy?

The heritability among monozygotic twins for NT1 was found to be 20-30%.
If a first-degree family member has NT1, your risk for NT1 increases by 10-40 times. This shows that there are some genetic and environmental factors that play an important role in narcolepsy.

There are multiple genes that are associated with NT1, but almost all patients with NT1 carry a specific variant of the human leukocyte antigen (HLA).
HLA system regulates immune functioning in the body.
The currently identified genetic factors do not fully reveal the heritability of narcolepsy.
However, narcolepsy has been associated with a significant reduction in orexin producing neurons in the brain. Orexin is a neurotransmitter that is considered the master regulator of the sleep-wake cycle. A deficiency of orexin-producing neurons can cause narcolepsy.

P2RY11 and Narcolepsy

The P2RY11 gene is a member of the G-protein coupled receptors family, expressed by the immune cells. It plays an essential role in immune functioning and cell death regulation.

Variations in the P2RY11 gene might dysregulate the functioning of certain immune cells like CD8+T-cells and contribute to the development of narcolepsy.

rs2305795 And Narcolepsy

The rs2305795 is a G>A polymorphism located in the P2RY11 gene on chromosome 19.
A study documented that the rs2305795 A allele is associated with a reduced immune response to infectious triggers, thereby contributing to narcolepsy risk.

Non-genetic Influences On Narcolepsy Risk

Some risk factors for narcolepsy include:
- Autoimmune effects
- Upper airway infection
- Sarcoidosis
- Head injury
- Stroke
- Tumor
- Age (10-30 years)

Effects of Narcolepsy on Health

1. People with narcolepsy find it harder to remember things and concentrate on doing an activity.
2. There is a risk of depression and anxiety.
3. Day to day activities like walking can become very dangerous when you fall asleep all of a sudden and lose muscle control.
4. The sudden loss of muscle control can lead to weakness of arms and legs.
5. People with narcolepsy may experience dream-like hallucinations, nightmares, and also paralysis when they sleep or wake up.
6. It affects your sleep cycle and quality of sleep. REM sleep movements tend to occur at any time of the day in people suffering from narcolepsy.

TipsTo Manage Narcolepsy

There is no cure for narcolepsy, but certain lifestyle changes and treatments can help you manage it.
1. Try to stick to a sleep schedule, including short naps for about 20 minutes during the day.
2. Avoid alcohol, nicotine, and caffeine consumption, especially at night, and eat healthily.
3. Include some exercise in your daily routine to make you feel more awake during the day and tired at night.
4. Try to avoid activities that may be dangerous if you fall asleep suddenly, like driving or get enough sleep before you do that activity if necessary.
5. Talk to everyone you work with about your condition. They need to be informed so that they can help you if needed and know how to react.
6. Your doctor may prescribe stimulant medicines to help you stay awake during the day and antidepressants to help with the nightmares and hallucinations.
7. Counseling and support groups can help you relieve your emotions and deal better with the condition.

Summary

1. Narcolepsy is a sleep disorder that usually appears during childhood or early puberty.
2. There are two types of narcolepsy: NT1 and NT2. The symptoms of narcolepsy include disturbed nocturnal sleep, excessive daytime sleepiness, and a few others.
3. Multiple genes are associated with NT1, but almost all patients carry a specific variant of the HLA gene that regulates immune functioning in the body.
4. The P2RY11 gene, expressed in immune cells, plays a role in immune functioning and cell death regulation. The A allele of SNP rs2305795 is associated with a reduced immune response to infectious triggers, contributing to narcolepsy risk.
5. Certain lifestyle changes like following a sleep schedule, taking short naps, exercising, reducing alcohol and nicotine consumption, and avoiding doing activities that may prove dangerous if you fall asleep suddenly can help manage narcolepsy.
6. Certain stimulants and antidepressant medications can be taken under the guidance of a trained medical professional.

References:

https://pubmed.ncbi.nlm.nih.gov/30652006/
https://pubmed.ncbi.nlm.nih.gov/21170044/
https://pubmed.ncbi.nlm.nih.gov/24381371/

Why Does Sleep Efficiency Matter?

Sleep efficiency refers to the percentage of time a person sleeps to the amount of time a person spends in bed. It is calculated by the ratio of the total time spent asleep (TST) in a night compared to the total amount of time spent in bed. An efficient sleep leads to a deeper sleep of better quality with lesser disturbances that may result in good stamina and sufficient rest upon waking, while an inefficient sleep may lead to uneasiness and fatigue.

Sleep Efficiency Rates

Sleep efficiency rates tend to vary from person to person. Normal sleep efficiency is considered to be 80% or greater. For example, if an individual spends 8 hours in bed, at least 6.3 hours or more should be spent sleeping to achieve 80% or greater sleep efficiency. Most healthy and young adults have sleep efficiencies above 90%.

How Does Genetics Influence Sleep Efficiency?

UFL1 Gene and Sleep Efficiency

UFL1 is one of the genes in the ubiquitin pathway - the principal mechanism behind protein breakdown.
This pathway has also been implicated in schizophrenia, a condition in which poor sleep efficiency is a common symptom.
The relevance of this pathway in sleep disturbances was further explored in another study.
The study indicated that the expression of a protein UFM1, a part of UFL1, increased after partial sleep restriction.

rs75842709 and Sleep Efficiency

A GWAS analysis found a significant correlation between a variant (rs75842709) near the UFL1 gene and sleep efficiency.
The T-allele was associated with a 5.7% decreased sleep efficiency.

Non-genetic Influences Of Sleep Efficiency

Some factors that lower sleep efficiency:
- Pain
- Higher fatigue
- Less activity during the day
- Light at night
- Jet lag
- Sleep environment

Tips To Improve Sleep Efficiency

1. Get some exercise during the day and get active.
2. Try to do a calm and relaxing activity, like taking a shower or reading a book before you sleep.
3. Avoid watching television or using your mobiles at least an hour before bedtime.
4. Eliminate distractions before sleeping. Avoid using flashy, blinking lights, having the television on, and using your cell phone.
5. Try to associate your bed with falling asleep and avoid doing other activities like reading or watching television on the bed before you fall asleep. Read at your table or any other convenient spot, and then fall asleep on your bed.
6. If you’re awake in the middle of your sleep time for more than 15-20 mins, try to move around and do some relaxing activity to fall asleep again.
7. Try to restrict your bedtime if most of it is spent laying awake. This can help meet your sleep needs but should be followed under the guidance of a doctor.

Summary

1. Sleep efficiency refers to the percentage of time a person sleeps to the amount of time a person spends in bed. Efficiency rates tend to vary from person to person.
2. The UFL1 gene involved in protein breakdown is implicated in schizophrenia, a condition in which poor sleep efficiency is a common symptom. The T allele of rs75842709 SNP is associated with a 5.7% decrease in sleep efficiency.
3. Pain, sleep environment, jet lag, higher fatigue, less activity during the day are some of the non-genetic influences on sleep efficiency.
4. Being active, doing calm and relaxing activities before sleeping, avoiding television and mobile usage before sleeping, and restricting bedtime to establish a proper sleep schedule can improve sleep efficiency.

Reference

https://pubmed.ncbi.nlm.nih.gov/27126917/

Sleep Latency: How Long Does It Take You to Fall Asleep?

Sleep latency (also known as sleep onset latency) refers to the amount of time it takes for a person to fall asleep. Usually, normal sleep latency is 5-15 minutes. If sleep latency is less than five minutes, it may suggest some level of excessive sleepiness, and if it is greater than 15 minutes, it may be due to sleep initiation issues.
Sleep latency varies from person to person. An ideal sleep latency period lays the foundation for a solid night's sleep. Sleep latency directly affects sleep efficiency, because if a person is able to fall asleep quickly, they are more likely to have an efficient sleep.

How Does Genetics Influence Sleep Latency?

Research studies have demonstrated the association between certain variants in RBFOX3 and DRD2 genes and sleep latency. The RBFOX3 gene plays a key role in neuron-specific alternative splicing (a process that removes the "unwanted" portions from the DNA and connects useful portions to form a functional gene).

RBFOX3 Gene and Sleep Latency

RBFOX3 also influences the release cycle of neurotransmitters, including GABA (gamma-aminobutyric acid) and various monoamines, vital to the human circadian clock.

DRD2 Gene and Sleep Latency

The DRD2 gene encodes a dopamine receptor. Dopamine is a 'happy hormone' that is crucial for signaling pleasure and reward. Dopamine and its receptors also play a part in controlling the sleep-wake cycle. Mainly, dopamine can help keep you awake and alert. The DRD2 gene variations may affect this wake/sleep switch, leading to a tendency for shorter sleep duration and sleep onset latency.

rs17601612 And Sleep Latency

The rs17601612 is a G>C polymorphism located in the DRD2 gene, which might affect the wake/sleep cycle. A study, Cade, Brian E., et al.2016, has shown that the rs17601612 C allele was strongly associated with shorter sleep latency than the G allele.

Non-genetic Influences on Sleep Latency

A variety of other factors influence sleep latency. They include:
- Age
- Gender
- Dietary intake
- Sedentary life
- Consumption of stimulants
- Illness such as depression

Effects of Delayed Sleep Latency on Health?

Prolonged sleep latency may shorten sleep duration and lead to a variety of problems, including depression, loss of productivity, irritability, cognitive impairment, poor academic performance in children, and adolescents. Persistently increased sleep latency is also a key indicator of delayed sleep phase syndrome, insomnia, sleep deprivation, and narcolepsy.

Tips To Improve Sleep Efficiency

1. Get some exercise during the day and be active.
2. Try to do a calm and relaxing activity, like taking a shower or reading a book before you sleep.
3. Avoid watching television or using your mobile at least an hour before bedtime.
4. Try to associate your bed with falling asleep and avoid doing other activities like reading or watching television on the bed before you fall asleep. Read at your table or any other convenient spot, and then fall asleep on your bed.
5. If you’re awake in the middle of your sleep time for more than 15-20 mins, try to move around and do some relaxing activity to fall asleep again.
6. Try to restrict your bedtime if most of it is spent laying awake. This can help meet your sleep needs but should be followed under the guidance of a doctor.

Summary

1. Sleep latency is the amount of time it takes for a person to fall asleep. It is usually in the range of 5-15 minutes. It varies from person to person.
2. Certain variants of RBFOX3 and DRD2 genes have an association with sleep latency. The DRD2 gene is a dopamine ('happy hormone') receptor. The C allele of an SNP rs17601612 located on this gene is associated with shorter sleep latency compared to the G allele.
3. Poor sleep latency shortens sleep duration and can lead to a variety of health issues.
4. Being active, doing calm and relaxing activities before sleeping, avoiding television and mobile usage before sleeping, and restricting bedtime to establish a proper sleep schedule can improve sleep efficiency.

References

https://pubmed.ncbi.nlm.nih.gov/27142678/
https://pubmed.ncbi.nlm.nih.gov/26464489/

What is Restless Leg Syndrome?

Restless Leg Syndrome (also known as Willis-Ekbom Disease) is a neurologic and sleep-related movement disorder characterized by an irresistible urge to move in the legs, which typically occurs or worsens at rest. Affected people may experience abnormal, uncomfortable sensations ( paresthesia or dysesthesias ) that are often linked to cramping, crawling, burning, aching, itching, or prickling deep within the affected areas.

This condition has a 10% prevalence rate, with an increase in incidences as age advances. Since the symptoms occur during sleep and relaxation, it could disrupt a good night's sleep.
Restless leg syndrome causes an uncomfortable urge to move, which can be relieved by walking or moving the extremities. This interferes with sleep maintenance

How Does Genetics Influence the Risk of Restless Leg Syndrome (RLS)?

Restless leg syndrome shows an anticipation inheritance - with each generation, the age of onset of this condition advances.

A GWAS meta-analysis study of restless leg syndrome (RLS) in European ancestry has demonstrated the significant association of RLS with MEIS1, BTBD9, PTPRD, and other genes.

BTBD9 and RLS

BTBD9 gene variants have been associated with RLS, with two experimental models providing better insights. The loss of this gene was associated with increased waking from sleep, motor activity, higher motor restlessness, and altered serum iron levels.

MEIS1 and RLS

The MEIS1 gene is a transcription factor that plays a key role in hematopoiesis, endothelial cell development, and vascular patterning.
It also plays a role in neurodevelopment.
Research studies have shown that the reduced MEIS1 levels and function of the gene may contribute to the pathogenesis of sleep-related disorders.

rs113851554 And RLS
The rs113851554 is a G>T polymorphism located in the MEIS1 gene, which is found to be correlated with multiple sleep disorders.

A GWAS meta-analysis study of RLS in European ancestry has demonstrated that the rs113851554 T allele is associated with an increased risk of developing RLS susceptibility.

Non-genetic Influences on RLS Risk

Some nutritional deficiencies have been implicated in RLS. They include:
- Vitamin D deficiency
- Iron deficiency

Some medical conditions associated with RLS are:
- Depression
- Diabetes
- Fibromyalgia
- Rheumatoid arthritis
- Hypothyroidism

Effects of Restless Legs Syndrome on Health

1. Many people with restless leg syndrome find it hard to fall asleep and have a good quality of sleep at night.
2. There is a risk of depression and other health problems.
3. Napping during the day becomes difficult.
4. It interferes with your day-to-day activities, concentration, and productivity.
5. It causes daytime sleepiness and fatigue.
6. About 80% of people with RLS have a condition called periodic limb movement of sleep which causes the legs to twitch or jerk during sleep. This leads to sleep deprivation.

Tips for Managing Restless Leg Syndrome (RLS)

Iron Supplements : Iron deficiency is one of the leading causes of RLS. If you test positive for iron deficiency, you may get started on iron supplements after consulting a qualified healthcare professional.
Baths and massages : Warm showers and massages can help relax muscles and prevent unnecessary leg movements.
Exercise : Restless Legs Syndrome foundation recommends moderate exercising to help manage RLS.
Avoid caffeine : High caffeine intake can worsen RLS. Either limit or avoid caffeine intake.

Summary

1. Restless Leg Syndrome is a neurologic and sleep-related movement disorder characterized by an irresistible urge to move in the legs, which typically occurs or worsens at rest. Symptoms occur during sleep, and relaxation disrupts a good night's sleep.
2. A significant association between MEIS1, BTBD9, PTPRD genes, and RLS has been established. The T allele of the rs113851554 SNP found in the MEIS1 gene is associated with an increased risk of developing RLS.
3. Vitamin D deficiency, iron deficiency, depression, and diabetes are associated with RLS.
   RLS leads to a risk of depression, other health problems, problems with napping, and sleep deprivation. It interferes with your day-to-day activities, concentration, and productivity.
4. Iron supplements, baths and massage, exercise, and caffeine can help manage restless leg syndrome.

Reference

https://pubmed.ncbi.nlm.nih.gov/29029846/

Introduction: What is Sleep Bruxism?

Sleep Bruxism (also known as Teeth Grinding) is defined as repetitive jaw muscle activity during sleep. It is characterized by an unconscious act of grinding or clenching one's teeth tightly together. Over time, it could lead to damage of teeth, oral health conditions, facial muscle pain, sleep disturbances, difficulty while speaking or eating.

Sleep Bruxism is more common in children, adolescents, and young adults than middle-aged and older adults.

The prevalence of sleep bruxism is estimated to be around 15% in adolescents, around 8% of middle-aged adults, and only 3% in older adults.

According to statistical studies 6-50% of children experience nighttime teeth grinding.

How Does Genetics Influence Sleep Bruxism Risk?

Multiple studies have demonstrated that there may be a degree of inherited susceptibility to develop sleep bruxism. According to a study, around 21-50% of affected individuals have an immediate family member who had sleep bruxism during childhood.

Few studies have shown the significant associations of certain variants in neurotransmitters like dopamine, serotonin, and others ( DRD3, HTR2A, COMT, MMP9, and others) with sleep bruxism.

DRD3 Gene and Sleep Bruxism

The DRD3 gene encodes the D3 subtype of the dopamine receptor, which is localized to the regions of the brain involved in cognitive, emotional, and endocrine functions.
Variations in DRD3 are implicated in the physiopathology of diseases affecting those functions.

rs6280 and and Sleep Bruxism

The rs6280 is a T>C polymorphism located in the DRD3 gene, where the C allele may increase dopamine affinity and efficacy. Studies have shown that the Gly variant (C) is significantly associated with increased susceptibility to sleep bruxism.

Non-genetic Influences on Sleep Bruxism Risk

Sleep bruxism may be accelerated by lifestyle factors as well. Some of them include:
- Stress
- Alcohol consumption
- Anxiety
- Cigarette smoking
- Upper airway resistance
- Caffeine consumption

Effects of Bruxism on Health

1. There is significant damage to the teeth. The teeth can become painful, shaky, and get eroded. Any implants have a risk of getting damaged.
2. It leads to problems with the temporomandibular joint (TMJ) which connects the lower jaw to the skull. This causes locking of the jaw, difficulty with chewing, popping, or clicking noises, and chronic jaw pain.
3. The sound from clenching and grinding your teeth can make it harder for the person you share your bed with to fall asleep.

Tips for Managing Bruxism

Mouth guards - Mouth guards help keep the teeth separated and hence prevent grinding.
Stress management - Stress is one of the major contributors to teeth grinding. So finding ways to alleviate stress can help prevent teeth grinding.
Avoid alcohol and caffeine - Teeth grinding tends to intensify upon alcohol and caffeine consumption.
Avoid chewing on pens and pencils - This practice gets your jaws used to grinding movement and may increase your tendency to grind your teeth.

Summary

1. Sleep Bruxism is defined as repetitive jaw muscle activity during sleep. Over time, it could damage teeth, oral health conditions, facial muscle pain, sleep disturbances, and difficulty while speaking or eating.
2. It is more common in children, adolescents, and young adults than in middle-aged and older adults.
3. Few studies have shown the significant associations of certain variants in neurotransmitters like dopamine, serotonin, and others DRD3, HTR2A, COMT, MMP9, and others with sleep bruxism.
   1. The C allele of rs6280 SNP found in the DRD3 gene, a dopamine receptor, is associated with increased susceptibility to sleep bruxism.
4. As sleep bruxism causes severe damage to the teeth over time and leads to problems with the temporomandibular joint, it needs to be managed. Using mouth guards, avoiding alcohol and caffeine, managing stress, and not chewing on pens and pencils can help.

References

https://pubmed.ncbi.nlm.nih.gov/32471213/
https://pubmed.ncbi.nlm.nih.gov/27611726/
https://pubmed.ncbi.nlm.nih.gov/28451935/
https://pubmed.ncbi.nlm.nih.gov/30092895/
https://pubmed.ncbi.nlm.nih.gov/25628080/

What is Sleep Fragmentation?

Sleep fragmentation is one of the symptoms of sleep disorders characterized by repeated, short sleep interruptions during the night, which leads to excessive tiredness during the day.

People with fragmented sleep tend to fall asleep quickly but wake up multiple times during the night for short periods. The other symptoms of fragmented sleep include morning headaches, daytime sleepiness, difficulty in concentrating, and memory lapses.

Fragmented sleep due to situational illness (like a cough or a sore back)is called short-term sleep fragmentation and goes away after some time.

Research studies have documented a greater impact on physical and emotional health when sleep quality and quantity are poor.

How Does Genetics Influence Sleep Fragmentation Risk?

A study reported the genetic and environmental variance in sleep complaints. The proportions were as follows:
1. At 8 years: 63% genetic, 32% non-shared environment
2. At 10 years: 66% genetic, 27% nonshared environment, 7% shared environment

The study also suggests that genetics affects sleep problems more strongly during the preschool/school age (63-69%) . Certain variants in HLA-DQB1, CRY1, and other genes might influence the risk of having fragmented sleep.

CRY1 and Sleep Fragmentation

The CRY1 gene encodes a protein called flavin adenine dinucleotide-binding, a key component of circadian clock regulation.
Variations in the CRY1 gene are found to be associated with altered sleep patterns.

rs184039278 and Sleep Fragmentation

The rs184039278 is an A>C gain of function mutation located in the CRY1 gene, associated with a prolonged period of circadian molecular rhythms.

A study, Patke, Alina, et al.2017, demonstrated that both CC and AC carriers are strongly associated with late sleep times and sleep fragmentation.

Non-genetic Factors That Influence The Fragmented Sleep Risk

Some sleep-related disorders can result in fragmented sleep. A few examples are:
1. Snoring
2. Obstructive sleep apnea
3. Sleep-maintenance insomnia
4. Restless leg syndrome

Poor sleep is also caused by lifestyle habits such as:
1. Alcohol and caffeine consumption
2. Napping for a long time in the day
3. Exercising close to bedtime

Effects of Sleep Fragmentation on Health

1. Sleep fragmentation reduces the amount of sleep you get at night and leads to extreme fatigue during the day.
2. It leads to a decrease in your concentration and productivity during the day.
3. There is a risk of weight gain and mood-related disorders.
4. It leads to increased stress and has a negative impact on your memory and cognitive function.
5. Over a period of time, there is a risk of heart diseases, obesity, and diabetes.
6. Behavioral problems in children are associated with sleep fragmentation.

Tips for Managing Sleep Fragmentation

You can follow these tips to have a peaceful night of sleep and avoid sleep fragmentation.
1. Tire yourself out: As fatigue accumulates throughout the day, it’ll be easier to fall asleep in the night.
2. Stay away from distractions: Switch off your phone, wear an eye mask, and shut the windows to prevent your sleep from being disturbed.

Summary

1. Sleep fragmentation is characterized by repeated, short sleep interruptions during the night, which leads to excessive tiredness during the day. This has a great impact on physical and emotional health.
2. The CRY1 gene encodes a protein called flavin adenine dinucleotide-binding, a key component of circadian clock regulation. The rs184039278 SNP found in this gene is associated with a prolonged period of circadian molecular rhythms, late sleep times, and sleep fragmentation.
3. Snoring, OSA, RLS, and bad lifestyle habits can also lead to sleep fragmentation.
4. Sleep fragmentation can lead to concentration, productivity, extreme fatigue, mood-related disorders, and other problems.
5. Tiring yourself out and staying away from distractions can help avoid sleep fragmentation.

References

https://pubmed.ncbi.nlm.nih.gov/20975052/
https://pubmed.ncbi.nlm.nih.gov/28388406/
https://pubmed.ncbi.nlm.nih.gov/24179306/

What makes a person an early riser or a night owl?

Chronotype is influenced by differences in circadian rhythm, which refers to the fundamental 24-hour physiological cycle essential for various molecular and behavioral processes. It helps regulate sleep patterns.

The timing of circadian rhythms varies across individuals and is influenced by both environmental and genetic factors. People with earlier rhythms tend to rise early in the morning and feel sleepy earlier in the night. If your body sides with the “morning clock” then you are a “morning person.” The other end of this spectrum has people with delayed rhythms. They tend to sleep and wake up late and are often referred to as an “evening person” or a “night owl.”

Research has shown that morning people are more focused, persistent, agreeable, plan their future better, and are less likely to smoke and drink or get depressed. They may exhibit characteristics like:
- Waking up early
- Being more active during the morning hours
- Being more focused and happy
- Being more productive during the day

Similarly, night owls enjoy a burst of strength during the night and may exhibit characteristics like:
- Waking up late
- Being more active during the evening hours
- Being more creative and adventurous
- Being more productive during the night

How Does Genetics Influence Circadian Rhythm?

A GWAS study of self-reported chronotype (morning/evening person) of UK Biobank data identified 22 regions in the circadian rhythm and photo-reception genes associated with morningness. This was also replicated in a 23andMe study.

One of the strongest associations was seen in the rs516134 SNP located near the RGS16 gene.

RGS16 Gene and Circadian Rhythm

The RGS16 gene encodes a protein that belongs to the regulator of G protein signaling. This protein is responsible for turning off certain signal communications between cells in the body.

Microarray studies and gene expression analysis have demonstrated that the RGS16 gene exhibits circadian variations. According to a study, mice lacking this gene have a longer circadian period.

rs516134 SNP and Morningness

The rs516134 is a C>T polymorphism located in the RGS16 gene. The C allele is found to be strongly associated with morningness.

Non-genetic Influences On Circadian Rhythm

A study found that morningness is significantly associated with gender, with a prevalence of 39.7% in males and 48.4% in females.

Also, people over 60 were more likely to prefer mornings than people under 30 - meaning people’s sleep preferences may change over time.

Effects of Circadian Rhythms

Circadian rhythms affect day-to-day bodily functions such as sleep, eating habits, hormones release, and body temperature.
Many studies have documented that irregular rhythms are linked to various chronic conditions such as sleep disorders, obesity, depression, diabetes, hypertension, bipolar, and schizophrenia.
It is known that the vast majority of patients with depression have sleep abnormalities; either they sleep too much or have insomnia and can’t sleep at all.
Several genetic variants are correlated with how circadian rhythms function and their association with health conditions.
The interplay between genetics and non-genetic factors (such as sunlight, eating habits) with circadian rhythm is clear.
Maintaining a routine with a balanced lifestyle may help to stabilize the internal biological clock and health.

Tips To Become An Early Riser

1. Sleep early and shift your bedtime gradually to get about 7-9 hours of sleep.
2. Stay consistent with your timings. Set your alarm clock to the same time every morning to make it easier to get into a routine.
3. Move your alarm clock to a distance where you would have to get up to turn it off. There are a few apps like Smart Alarm or Math Alarm which require you to do an activity to turn off the alarm. This will help you stay awake and not snooze your alarm and go back to sleep.
4. Exposure to bright light in the morning, especially natural light, helps make you alert and gets you used to wake up early. Your body’s circadian rhythm is responsive to light and dark conditions.
5. Get active in the morning and go for a jog or run. You can even hit the gym in the morning and finish your workout. This will give you the energy to start your day.
6. Think about the various reasons why waking up in the morning could be beneficial and how you can be more productive during the day.
7. Use something to look forward to in the morning as bait to wake up for. A cup of hot coffee, a nice breakfast, a puzzle in the newspaper are a few of the things that you could look forward to.
8. A protein-heavy meal is said to increase your dopamine levels, facilitating wakefulness, and making you ready for the day.

Summary

1. Circadian rhythm, which refers to the fundamental 24-hour physiological cycle essential for various molecular and behavioral processes, helps regulate your sleep patterns.
2. People with earlier rhythms are termed as morning people, whereas those with delayed rhythms are termed as night owls. Morning people are known to be more focused and happy, while night owls are known to be more creative and adventurous.
3. Both environmental and genetic factors influence your sleep patterns.
4. Several genes are known to affect circadian rhythm. The C allele of the rs516134 SNP in the RGS16 gene, which is involved in turning off certain signals between cells in the body, is known to be strongly associated with morningness.
5. Circadian rhythms affect your day-to-day functions, and irregularity is associated with chronic health conditions.
6. Following a routine with a balanced and healthy lifestyle can help set your biological clock right.

References:

https://pubmed.ncbi.nlm.nih.gov/27494321/
https://pubmed.ncbi.nlm.nih.gov/26835600/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5428740/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4018537/

Introduction

Sleep is a critical component of optimal health. A healthy sleep comprises various aspects, including adequate duration, good quality, and the absence of sleep disorders. Inadequate sleep at night is generally associated with:
- Daytime sleepiness
- Daytime fatigue
- Depressed mood
- Poor functioning
- Other health issues

Sleep duration refers to the total amount of sleep obtained either during the nighttime sleep event or across the 24-hr period.

Importance of An Adequate Sleep

Getting enough sleep at night is very important for several reasons. Sleep is linked to your mental and physical health and quality of life. When you get adequate sleep at night, you can be more productive and concentrate better during the day. It reduces your risk of heart disease and prevents depression. Your immune system becomes stronger as sleep helps the body to repair and recover. Your athletic performance can also be improved because of a good night’s sleep. Not getting enough sleep can make you gain weight faster.

RDA: What Is The “Ideal” Sleep Duration?

National Sleep Foundation guidelines recommend 7-9 hours of sleep per night for healthy adults. Babies, young children, and teens need even more sleep to enable their growth and development. People over 65 should also get 7 to 8 hours of sleep per night.

How Does Genetics Affect Sleep Duration?

Studies have shown that certain genetic variants influence habitual sleep duration, which explains why some individuals need more sleep than others.
Twin studies have shown that the heritability estimation of sleep duration is around 10 - 40%.

A GWAS study of self-reported chronotype and sleep duration of UK Biobank data identified several genetic regions associated with sleep duration. This study documented that people with genetic variants for longer sleep duration reported an average of 22 minutes more sleep.

PAX8 Gene and Sleep Duration

The PAX8 gene encodes a member of the paired box (PAX) family of transcription factors involved in thyroid follicular cell development and the expression of thyroid-specific genes.

Variations in the PAX8 gene may affect different functions, including DNA binding, gene activation, and protein stability.

Research studies have found that the sleep-wake cycle may be influenced by regulating thyroid hormone levels. Individuals with hypothyroidism (a condition in which the thyroid gland does not produce enough thyroid hormones) are prone to excessive sleepiness. People with hyperthyroidism (in which the thyroid makes too much of the hormone), on the other hand, may have insomnia.

rs62158211 And Sleep Duration

The rs62158211 is a G>T polymorphism located in the PAX8 gene. The T allele is associated with longer sleep duration.
A study documented that the rs62158211 was associated with an average 2.6-minute per-allele change in sleep duration.

Non-genetic Influences On Sleep Duration

Some risk factors that lead to shorter sleep duration include alcohol consumption, smoking, and physical inactivity.

Effects of Sleep Duration on Health

Few epidemiological and genetic studies have demonstrated a strong biological link between abnormal sleep duration, risk of schizophrenia, type 2 diabetes, fetal growth, and Crohn's disease.

Sleep duration is also associated with cardiovascular diseases, type 2 diabetes, depression, automobile and workplace accidents, learning and memory problems, and prospective mortality.

TipsTo Become An Early Riser

1. Sleep early and shift your bedtime gradually to get about 7-9 hours of sleep.
2. Stay consistent with your timings. Set your alarm clock to the same time every morning to make it easier to get into a routine.
3. Move your alarm clock to a distance where you would have to get up to turn it off. There are a few apps like Smart Alarm or Math Alarm which require you to do an activity to turn off the alarm. This will help you stay awake and not snooze your alarm and go back to sleep.
4. Exposure to bright light in the morning, especially natural light, helps make you alert and gets you used to waking up early. Your body’s circadian rhythm is responsive to light and dark conditions.
5. Get active in the morning and go for a jog or run. You can even hit the gym in the morning and finish your workout. This will give you the energy to start your day.
6. Think about the various reasons why waking up in the morning could be beneficial and how you can be more productive during the day.
7. Use something to look forward to in the morning as bait to wake up for. A cup of hot coffee, a nice breakfast, a puzzle in the newspaper are a few of the things that you could look forward to.
8. A protein-heavy meal is said to increase your dopamine levels, facilitating wakefulness, and making you ready for the day.

Summary

1. Sleep duration refers to the total amount of sleep obtained during the nighttime sleep event or across the 24-hr period. Getting enough sleep at night is necessary for both mental and physical well-being.
2. For healthy adults, 7-9 hours of sleep is recommended. Babies, children, and teens tend to sleep for much longer.
3. Genetics is found to influence sleep duration. The PAX8 gene, which plays a role in thyroid development, is associated with the sleep cycle. The regulation of thyroid hormone levels affects the sleep-wake cycle. The T allele of the rs62158211 SNP in this gene is associated with longer sleep duration.
4. Certain risk factors like smoking, alcohol consumption, and physical inactivity lead to decreased sleep duration.
5. Abnormal sleep duration is linked with the risk of schizophrenia, type 2 diabetes, fetal growth, and Crohn's disease.
6. Exercising during the day, following a proper sleep routine, reducing alcohol consumption and smoking, a comfortable environment, and less frequent napping are some of the things that can make your sleep duration normal.

References:

https://www.sleepfoundation.org/articles/how-much-sleep-do-we-really-need
https://pubmed.ncbi.nlm.nih.gov/27992416/
https://pubmed.ncbi.nlm.nih.gov/27494321/
https://pubmed.ncbi.nlm.nih.gov/25469926/