What Is A Chronotype?

Research shows that your bedtime may actually be linked to your DNA! Everyone’s biological clock is wired differently; it’s not in sync. Environmental and genetic factors affect your circadian rhythm, or your internal clock. Circadian rhythms, in turn, influence your sleeping pattern.  

Your preferred sleeping pattern is called your ‘chronotype.’ Going to sleep around 11 PM and waking up around 7 AM puts you in the average chronotype category. Someone with an average chronotype gets roughly the same amount of sleep on both working and non-working days, and this is good.  

About 40% of the population does not belong to this category. They have late or early chronotypes. These people will find it pretty difficult to go to work after a free day. They may even experience symptoms of jet lag.

What contributes to the difference in chronotypes?

Melatonin: The Sleep Hormone

Melatonin is the "sleep hormone" that regulates the sleep-wake cycle in the body. It is produced by a neuron bundle called Suprachiasmatic Nucleus or SCN for short. 

For people with the average chronotype, melatonin production starts around 9 PM, and the whole body enters into the 'rest mode' by 10:30 PM. The body temperature enters its lowest around 4:30 AM. These people usually wake up around 6:45 AM when the blood pressure spikes to the highest point. They are known as the 'early risers' and are alert and active during the daytime. 

For people with the late chronotype, this whole cycle happens later during the day. As a result, they tend to sleep and wake up much later. 

They may not entirely be able to fix this. This is because the CLOCK genes found in the SCN neuron bundle regulate the 24-hour cycle in your body. Changes in the CLOCK genes influence your chronotype status - average, or early, or late.

A study was carried out on hamsters to study the contributing factors to chronotype. Scientists replaced the SCN of early chronotype hamsters with that of average chronotype hamsters. To their surprise, the hamsters still went to sleep and woke up early, according to their early chronotype. 

This is because, other than the SCN clock, the body also contains other biological clocks, all of which contribute to a person’s chronotype. And, this is why it can be very difficult to break out of your natural sleeping pattern. 

Chronotype Genetic Test

To know what your chronotype is based on your genes, you can get a genetic test done. Most genetic tests provide your DNA information in the form of a text file called the raw DNA data. At Xcode Life, can help you interpret this data.

All you have to do is upload your raw data and order a sleep report. Xcode Life then analyzes your raw data in detail to provide you with a comprehensive sleep analysis, including information on your chronotype and risk for various sleep disorders.

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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.

Video

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 Insomnia?

Insomnia (also known as sleeplessness) is a common sleep disorder that is characterized by the inability to fall asleep or stay asleep at night, resulting in tired or unrefreshing sleep.

According to the American Psychiatric Association (APA), insomnia is the most common sleeping disorder.

Approximately 30% to 40% of adults in the United States report symptoms of insomnia.

A diagnosis of insomnia needs to meet the following two categories:
- Difficulties in sleep for at least three nights a week for a minimum of three months
- Difficulties in sleep that results in functional distress in the individual’s life

This can be caused by variations in biological, psychological, and social factors, which most often result in a reduced amount of sleep.

How Does Genetics Influence Insomnia Risk?

A research study published in 2019 found an association between certain variants in genes like DLG4, LRRK2, DNM1, CRH, GRIN1, DRD1, DRD2, SNCA, DRD4, NTSR1, CNTN2, and CALB1, and insomnia. DNM1 gene codes for the synaptic neuronal protein dynamin 1, which is associated with pre-sleep arousal, a characteristic feature among people with insomnia.

According to a research study, the heritability of insomnia is between 38 to 59%. This suggests a role of genetic factors in insomnia.

Tissue-specific gene-set analyses showed that insomnia might have higher genetic signals among genes that are usually expressed in the brain. The functions of these regions of the brain are of relevance to insomnia.

The genetic correlations between insomnia and psychiatric traits were stronger than the genetic correlations between insomnia and other sleep-based characteristics. According to the study, this suggests that genetically, insomnia resembles neuropsychiatric traits more closely than other sleep-related characteristics.

MEIS1 Gene and Insomnia

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 Insomnia Risk

The rs113851554 is a G>T polymorphism located in the MEIS1 gene, which is found to be correlated with multiple sleep disorders.
A study found that the T allele of rs113851554 is associated with [an increased risk of developing insomnia symptoms] (https://pubmed.ncbi.nlm.nih.gov/27992416/). Also, functional study analysis suggested that the rs113851554 in the MEIS1 locus is most strongly associated with insomnia disorder.

Non-genetic Influences On Insomnia Risk

Insomnia is more common in women than in men. In fact, women are twice as likely to fall asleep than men. One in four women has some insomnia symptoms.

Insomnia is more common in older people more than men and younger ones. As many as 50% of older adults complain about difficulty initiating or maintaining sleep.

Effects Of Insomnia On Health

1. Increased risk of heart disease, stroke, inflammation, obesity, seizures, diabetes, and asthma.
2. Increased risk of anxiety and depression.
3. A negative impact on your memory.
4. You find it harder to concentrate and be productive during the day.
5. Lack of sleep can make you more prone to falling and accidents by affecting your balance.
6. Insomnia can lower your life expectancy as reported by a study.

TipsTo Prevent And Manage Insomnia

1. Try to wake up at the same time every day and follow a routine to control your sleep cycle.
2. Avoid napping during the day for a long time.
3. Don’t eat right before going to bed and reduce alcohol consumption.
4. Do some physical activity every day. It helps improve sleep quality and duration.
5. Reduce your stress before sleeping and set up a comfortable environment.
6. Massage therapy is known to help people with insomnia sleep better. Meditation can also be helpful.
7. If lifestyle changes don’t work out for you, consult a doctor to understand the underlying health condition, and take the right medication.

Summary

1. Insomnia, the inability to fall asleep or stay asleep at night, is the most common sleeping disorder.
2. This can be caused by variations in biological, psychological, and social factors, resulting in a reduced amount of sleep.
3. There are genetic correlations between insomnia and psychiatric traits. The MEIS1 gene, known to play a role in neurodevelopment, may contribute to the pathogenesis of sleep-related disorders. The T allele of the rs113851554 SNP is associated with an increased risk of developing insomnia symptoms.
4. Insomnia is found to be more common in women than in men.
5. Sticking to a proper routine, exercising, less frequent napping, reducing stress, massage therapy, and reducing alcohol consumption and smoking can help prevent and manage insomnia.

References

https://pubmed.ncbi.nlm.nih.gov/30804565/
https://pubmed.ncbi.nlm.nih.gov/26132482/

Caffeine and Sleep

Caffeine is a central nervous system stimulant, which is widely used for its psychoactive effects. It is commonly used to alleviate behavioral, cognitive, and emotional deficits caused by sleep deprivation.

Regardless of its beneficial effects, caffeine may have adverse sleep-related consequences that might lead to sleep disruption and insomnia symptoms. This is because caffeine consumption is associated with lower levels of 6-sulfatoxymelatonin. 6-sulfatoxymelatonin is a substance produced during the metabolism of melatonin. It is involved in the regulation of circadian rhythm. Lower levels of 6-sulfatoxymelatonin can result in increased alertness (wakefulness).

How Does Genetics Influence The Risk of Caffeine-induced Insomnia?

CYP1A2 encodes cytochrome P-450 group of enzymes. These enzymes influence the absorption and metabolization of caffeine. Caffeine is absorbed rapidly and completely from the gastrointestinal tract. After absorption, the P-450 enzymes help with the metabolization. Variation in the CYP1A2 activity represents a major source of variability in the pharmacokinetics (drug absorption, distribution, metabolism, and excretion) of caffeine.

While the CYP1A2 gene is responsible for caffeine metabolism, another gene, ADORA2A, influences how your sleep is affected by caffeine intake. This gene encodes the adenosine receptor. When an adenosine molecule binds to this receptor, it inhibits all the processes that are associated with wakefulness. Caffeine acts as an adenosine receptor antagonist - it mimics adenosine and goes and binds to the adenosine receptor. This results in increased levels of free adenosine, leading to a boost in neuronal activity and wakefulness.

The adenosine A2A receptor (ADORA2A receptor) plays a role in the effects of caffeine on arousal. Mice lacking functional A2A receptors do not show increased wakefulness in response to caffeine administration, indicating that the A2A receptor mediates the arousal response.

rs5751876 and Caffeine-induced Insomnia

The rs5751876 is a T>C polymorphism located in the ADORA2A gene, which modulates the sleep-wake cycle, and contributes to individual sensitivity to caffeine effects on sleep.
Studies have documented that in caffeine consumers (less than 300mg), rs5751876 - T allele is associated with a decreased risk of sleep complaints and insomnia as compared to the C allele.

Non-genetic Influence on Caffeine-induced Insomnia Risk

1. Regular consumption - Researchers found that the effects of caffeine on sleep are higher in occasional coffee drinkers compared to those who drink coffee regularly.
2. Age and weight - Few studies have reported that older adults are more sensitive to the effects of caffeine compared to younger people. The exposure of caffeine in the body may also differ based on the weight of the person.
3. Time - Consuming caffeine closer to bedtime can disrupt sleep more than when consumed during the day.

Effects of Caffeine-induced Insomnia

If caffeine consumption is not wisely regulated, it could lead to delayed sleep and sleep deprivation. Sleep deprivation is associated with lapses in attention, lowered alertness, and reduction in cognitive function. Scientific studies have shown that a reduction in sleep time of 90 minutes could reduce objective alertness during the day time by one-third.

Tips for Regulating Caffeine Consumption

1. Moderate your consumption of caffeine. Do not drink caffeinated beverages post 5:00 pm or 5-6 hours before sleeping, as the effects of caffeine last for up to 6 hours after consumption.
2. Chamomile tea is considered to be a mild tranquilizer or sleep inducer. It contains the antioxidant apigenin, which may promote sleep.

Summary

1. Caffeine, a central nervous system stimulant, may have adverse sleep-related consequences that might lead to sleep disruption and insomnia.
2. Genes like CYP1A2 and ADORA2A influence caffeine-induced insomnia. CYP1A2 is related to caffeine metabolism while _ADORA2A influences how your sleep is affected by caffeine intake.
3. The T allele of rs5751876 SNP in the ADORA2A gene is associated with a decreased risk of insomnia than the C allele.
4. Age, weight, time of consumption, and frequency of consumption are the non-genetic influences on caffeine-induced insomnia.
5. Moderated caffeine consumption during the day at least 5-6 hours before sleep is recommended to prevent caffeine-induced insomnia. Chamomile tea can also be consumed as it is a sleep inducer.

Reference

https://pubmed.ncbi.nlm.nih.gov/31817803/
https://pubmed.ncbi.nlm.nih.gov/15965471/

What is Obstructive Sleep Apnea?

Obstructive Sleep Apnea (OSA) is a common, serious, and potentially life-threatening sleep disorder. It is characterized by frequent episodes of partial or complete upper airway obstruction during sleep.
This results in intermittent hypoxemia (low level of oxygen in the blood) and arousal.
Here, the throat muscles relax at irregular intervals and fail to keep the airway open. This results in inadequate breathing for 10 seconds or longer. Thus, the oxygen levels lower, and carbon dioxide levels build up. The brain interprets this as a need to open the airway and wakes you up in the process. This awakening is usually too brief to be remembered. A very noticeable sign of OSA is snoring.

More than 18 million American adults have been estimated to have sleep apnea.

How Does Genetics Influence the Risk of Obstructive Sleep Apnea?

Genes thought to be associated with the development of obstructive sleep apnea are involved in many body processes. They include:
- Communication between nerve cells
- Breathing regulation
- Control of inflammatory responses by the immune system
- Development of tissues in the head and face (craniofacial development)
- The sleep-wake cycle
- Appetite control

African-Americans and Pacific Islanders have more genetic variants associated with sleep apnea than Europeans. Variations in genes such as TNF, CRP, PLEK, PTGER3, LPAR1, HTR2A, and GDNF are associated with the risk of obstructive sleep apnea. Studies suggest that variations in multiple genes, each with a small effect, combine to increase the risk of developing the condition.

TNFA Gene and Obstructive Sleep Apnea

The TNFA gene encodes a proinflammatory cytokine (a molecule released by the T-immune cells) that belongs to the tumor necrosis factor (TNF) superfamily. It regulates various biological processes, including cell proliferation, differentiation, apoptosis, lipid metabolism, and coagulation. Studies have shown that TNF is involved in the regulation of sleep by influencing the adenosine receptor expression.

rs1800629 And Obstructive Sleep Apnea

The rs1800629 is G>A polymorphism located in the TNFA gene associated with increased transcriptional activity and higher TNF levels. This SNP has been studied to contribute to the pathogenesis of sleep disorders. Studies have shown that the rs1800629 - A allele carriers are associated with an increased risk of developing obstructive sleep apnea when compared to G allele carriers.

Non-genetic Influences On OSA Risk

Some non-genetic risk factors for OSA are:
- Narrowed airway
- Smoking
- Hypertension
- Obesity
- Gender
- Menopause
- Diabetes

According to a 2013 study, people with type 2 diabetes have nearly a 50% chance of being diagnosed with OSA. Both of these often coexist because of shared risk factors.

Effects Of OSA on Health

Some effects of OSA that could interfere with everyday functioning include:
- Difficulty in concentrating
- Excessive daytime sleepiness
- Irritability, sexual dysfunction
- Nighttime sweating
- Learning and memory difficulties

Tips for Managing Obstructive Sleep Apnea

1. Having a consistent sleep cycle routine, maintaining a healthy weight, avoiding smoking and alcohol consumption, a comfortable bedroom environment, and exercise during the day are some of the lifestyle changes that can help prevent and also manage obstructive sleep apnea.
2. If following lifestyle changes don’t help you manage your sleep apnea, do consult a doctor. This applies to moderate and severe sleep apnea.
3. The doctor may ask you to use an oral device (mouthpiece) designed to keep your throat open and keep your airway open.
4. Positive airway pressure treatment reduces the respiratory events that occur when you sleep, thereby reducing snoring also.
5. In some cases, surgery is also done to manage obstructive sleep apnea.

Summary

1. Obstructive Sleep Apnea (OSA) is characterized by frequent episodes of partial or complete upper airway obstruction during sleep. Snoring is a notable sign of OSA.
2. Variations in multiple genes, each with a small effect, combine to increase the risk of developing the condition.
3. TNFA gene, which encodes a molecule produced by immune cells, is involved in regulating sleep by influencing the adenosine receptor expression. The A allele of SNP rs1800629 is associated with an increased risk of developing OSA compared to the G allele.
4. OSA can lead to difficulties in concentration, learning, memory, excessive daytime sleepiness, and nighttime sweating.
5. A consistent sleep cycle routine, healthy weight, and reducing alcohol consumption are some lifestyle changes to help manage OSA. An oral device and positive airway pressure treatment are also used in some cases under the guidance of a medical professional.

References

https://pubmed.ncbi.nlm.nih.gov/22043116/
https://pubmed.ncbi.nlm.nih.gov/23155414/
https://pubmed.ncbi.nlm.nih.gov/20538960/

What is Excessive daytime sleepiness?

Excessive daytime sleepiness (also known as hypersomnia) refers to the inability to stay awake and alert during the normal waking hours that results in unexpected lapses of sleep or drowsiness. It can even occur after long stretches of sleep.

There are two types of hypersomnia; primary and secondary.
Primary hypersomnia occurs without an underlying medical condition. The only symptom is excessive fatigue.
Secondary hypersomnia, on the other hand, occurs due to a medical condition.

Some symptoms of hypersomnia include:
- Anxiety
- Irritability
- Low energy
- Loss of appetite
- Restlessness

A 2019 study in Nature Communications documented that nearly 10–20% of people deal with excessive sleepiness to some degree.

How Does Genetics Influence the Risk of Excessive Daytime Sleepiness?

Studies have shown that certain genetic variants influence daytime sleepiness, which explains why some individuals need more sleep than others. Twin study results have estimated a 38% genetic variance in daytime sleepiness.

Studies have found an association between excessive daytime sleepiness and certain variations in the HCRTR2, PATJ, AR-OPHN1, KSR2,, and PDE4D genes.

The HCRTR2 gene encodes a protein that belongs to the G-protein coupled receptor, involved in the regulation of appetite, energy balance, neuroendocrine functions, and wake promotion.
Latest research studies suggest that variations in the HCRTR2 gene may influence the sleep-wake process.

Non-genetic Influence on EDS Risk

The most common causes of excessive sleepiness include:
- Low sleep duration
- Poor quality sleep
- Sleep deprivation
- Obstructive sleep apnea
- Medications with sedative properties
- Narcolepsy

Research has also indicated that other health conditions can increase the risk of excessive sleepiness. Some of them include:
- High BMI (Obesity)
- Type 2 diabetes
- Depression

Effects Of Excessive Daytime Sleepiness (EDS) on Health

Studies have shown that EDS is associated with an increased risk of developing coronary heart disease and stroke. However, the risk can be managed by improving the quality of sleep.
People with EDS also have poorer health than comparable adults.
According to a study, EDS is associated with negative effects on cognitive function. In fact, EDS is a common symptom in neurological conditions like Parkinson’s and psychiatric conditions like depression.

Tips for Managing Obstructive Sleep Apnea

1. Having a consistent sleep cycle routine, maintaining a healthy weight, avoiding smoking and alcohol consumption, a comfortable bedroom environment, and exercise during the day are some of the lifestyle changes that can help prevent and also manage obstructive sleep apnea.
2. If lifestyle changes don’t help you manage your sleep apnea, do consult a doctor. This applies to moderate and severe sleep apnea.
3. The doctor may ask you to use an oral device (mouthpiece) designed to keep your throat and airway open.
4. Positive airway pressure treatment reduces the respiratory events that occur when you sleep, thereby reducing snoring also.
5. In some cases, surgery is also done to manage obstructive sleep apnea.

Summary

1. Excessive daytime sleepiness refers to the inability to stay awake and alert during the normal waking hours, resulting in unexpected lapses of sleep or drowsiness.
2. Anxiety, low energy, restlessness, loss of appetite, and irritability are the symptoms of hypersomnia.
3. The HCRTR2 gene encodes a protein involved in the regulation of appetite, energy balance, neuroendocrine functions, and wake promotion. Variations in this gene may influence the sleep-wake process and influence hypersomnia.
4. Sleep deprivation, OSA, poor quality of sleep, low sleep deprivation, certain medications, and narcolepsy are some of the non-genetic factors that are associated with insomnia hypersomnia.
5. Various lifestyle changes can help manage this disease. It can also be treated by treating the underlying cause like sleep apnea.

References:

https://pubmed.ncbi.nlm.nih.gov/31409809/
https://pubmed.ncbi.nlm.nih.gov/27992416/
https://pubmed.ncbi.nlm.nih.gov/29783161/

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/