Carrier Screening analyzes if a person carries or possesses the gene for a particular genetic disorder.
The test is mostly performed before or during pregnancy to find out if the couple has the chances of having a child with any genetic disorder.
A 'carrier' is an individual who has a single allele associated with a genetic disease.
Carriers usually don't experience any symptoms or just mild symptoms.
They are generally not even aware that they have a gene that causes a disorder.
Genetic carrier screening is testing to find out if you or your partner carry any genetic mutation that could cause severe inherited disorders in your child.
The most commonly screened diseases and health conditions include cystic fibrosis, thalassemia, Tay-Sachs disease, and sickle cell disease.
Foresight Carrier Screen helps you find out if you carry mutations (genetic changes) that could be responsible for severe genetic disorders in your offsprings.
For most of the conditions, your children might be at risk of developing symptoms only if both parents carry one mutation in the same gene.
However, there are certain disorders which can be passed on to children even only the mother carries the mutation.
Your foresight carrier screen results can help you make informed decisions along with your partner about your family, especially if it is done before pregnancy.
A gene in an organism can be of two types- homozygous or heterozygous.
A homozygous condition arises due to the presence of two copies of the same allele for a gene.
The presence of two different alleles of a gene is called heterozygous.
Individuals who are carriers are always heterozygous.
A complete or a partial change in a DNA sequence compared to its standard form can cause a genetic disorder.
While a mutation in one gene causes a monogenic disease, a mutation occurring in multiple genes causes multifactorial inheritance.
Some of the other factors include environmental factors and chromosomal abnormalities.
Genetic disorders occur when a person inherits a particular mutated disease-causing gene.
The mutated gene gets passed down through a family with each child inheriting the disease-causing gene.
Also known as carrier rate, it is the proportion of people in a population who possess a single copy of a particular recessive gene mutation.
It is sometimes also applied to the prevalence of mutations in dominantly acting genes.
Blood or saliva samples are drawn and sent to the laboratory.
The sample is then processed and examined to find out mutations that are responsible for genetic disorders.
It can take several weeks to obtain the results which may indicate as to whether or not you have the variation associated with any genetic diseases.
Genetic testing can reveal mutations in your genes that could be responsible for diseases or disorders.
Despite providing essential information about diagnosing, treating and preventing these diseases, genetic testing has certain limitations.
For instance, in an average, healthy person, a positive result obtained from a genetic test doesn't necessarily mean that they will develop the disease or condition.
Likewise, a negative result does not necessarily imply that an individual would not develop the condition.
It is important to discuss your results with your doctor, medical geneticist or a genetic counselor.
Genetic testing determines your risk of developing certain diseases.
They may be used for the following purposes:
Diagnosing testing- Used to confirm a diagnosis, when you have symptoms of a genetic disorder.
Presymptomatic & Predictive testing- When you have a family history of a genetic disorder, you can get this done before you experience any symptoms to find out if you might be at risk of developing it.
Carrier testing- Done before you plan for a child, this testing detects if you or your partner possesses genes associated with any genetic diseases and mutations and if either of you might be carriers for those diseases. Carrier screening is recommended to individuals who belong to a high-risk ethnic group or those with a family history of genetic disorders.
Pharmacogenetics- For individuals suffering from certain diseases or health conditions, this testing can help determine the most effective and beneficial kind of medications and dosages for you.
Prenatal testing- This test is done during pregnancy to detect abnormalities in the genes of the fetus. Amniocentesis is performed to screen for genetic disorders like Down syndrome and trisomy 18. Also, there is a new method called cell-free DNA testing that explores a baby's DNA via a blood test done on the mother.
Newborn Screening- This is done to test for genetic and metabolic abnormalities in newborns. Since this type of testing can detect disorders like congenital hypothyroidism, sickle cell disease, and other conditions. Newborn screening ensures early detections and treatment of genetic diseases in newborns.
Preimplantation testing- When couples attempt to conceive a child via in-vitro fertilization methods, the embryos could be screened to detect genetic abnormalities. This way, only embryos without abnormalities are implanted in the uterus.
Breast & Ovarian Cancers- About 5-10% of these cancers occur due to 3 mutations in the genes BRCA1 or BRCA2. The BRCA genes belong to a class of genes known as tumor suppressor genes. Women with these mutations are five times more likely to develop breast cancer and 15-40 times more likely to develop ovarian cancer.
Celiac disease- Affecting about 2 million Americans, this is an autoimmune disease triggered by a protein called gluten that is found in wheat, rye, and barley. The disease occurs in the small intestine leading to diarrhea and pain in the abdominal area. According to a 23andMe study, around 87% of the disease is attributed to genetics. The geneticist usually tests for HLA-DQ, a protein from the immune system which is encoded by a set of genes located on chromosome 6. About 1 in 22 people with an immediate relative such as a parent, sibling or a child with the disease are likely to develop the disease themselves. Moreover, those with a second-degree relative (uncles, aunts, nieces, nephews, grandparents, grandchildren or half-siblings) have a risk of 1 in 39.
Age-related Macular Degeneration (AMD)- One of the most common causes of irreversible loss of vision in Americans who are older than 60. AMD causes one's retina to deteriorate and result in central vision loss that is essential for reading, driving or facial recognization. Per 23andMe, While both genetics and environmental factors are responsible for the development of the disease, heredity attributes to around 71% of the cases. Genetic testing focuses on ABCR genes. According to the Macular Degeneration Foundation, individuals with variations in these genes have a 30% higher chance of acquiring AMD.
Bipolar disorder or the manic-depressive disorder- A mental illness marked by severe mood swings from despair to euphoria affects 5.7 millions of Americans aged 18 and older, according to the National Institute of Health (NIH). The disorder has a strong genetic component even though researchers have identified very few associated SNPs. According to a study by 23andMe, around 93% of the cases are due to genetic factors. Genetic testing for bipolar disorder looks for a protein marker encoded by the gene ANK3 that is associated with nerve cell structure and function. Per the Center for Genetic Education in Australia, an average person has 2-3% chances of developing the disorder, and the risk only gets higher with the increase in the number of relatives affected and their degree of relatedness. Individuals with a mutation on a gene called Fat located on chromosome 4 has twice the risk of developing bipolar as the average person.
Obesity- With as high as one-third of Americans affected by this condition, researchers haven't yet figured out the number of genes responsible for it. Although, according to 23andMe, genetic factors attribute to almost 84% of obesity. Mutations in the gene FTO accounts for nearly 7 pounds of weight difference.
Parkinson's disease- The neurological disorder caused due to a loss of dopamine-secreting brain cells. Common symptoms include trembling limbs, jaws and face, stiffness in the trunk and legs, reduced movements and impaired coordination and balance. An NIH study shows that at least 500,000 Americans have been diagnosed with this disease. Mutations in the gene LRRK2 is associated with an increased risk of developing Parkinson's disease. There are more than 50 known variations of the gene with several ones related to the disease.
Psoriasis- The highest prevalent autoimmune disease in the United States with almost 7.5 million sufferers, as reported by the National Psoriasis Foundation. Psoriases is characterized by red, scaly lesions covering any part of the one's body. Per 23andMe, about 80% of the condition is attributed to genetics and occurs whenever the T-cells attack the skin. HLA-C gene mutations and seven other DNA variations have been linked to psoriasis. Although, environmental factors play a role in the development of psoriasis, and only about 10% of patients with HLA gene variations do so.
You can be a genetic carrier for the following diseases:
X-Linked Hemophilia
Cystic Fibrosis
Sickle Cell Anemia
Marfan Syndrome
Tay-Sachs disease
Fragile X Syndrome
Duchenne muscular dystrophy
Spinal muscular atrophy
Genetic testing can cost you from $100 and exceed $2000 depending on the type and complexity of the test.
It will also depend on the number of tests- whether its a single test or if multiple family members would be taking it to obtain a meaningful result.
Newborn screening costs vary from state to state. While some states cover part of the total cost, others may charge $15 to $60 per infant.
While most carriers are asymptomatic, i.e., (exhibiting no symptoms), certain others do experience some mild symptoms.
For instance, approximately one in 31 Americans is an asymptomatic carrier of a defective CF gene.
Carrier screening is a significant step forward to making informed decisions concerning family planning.
Carrier screening enables prospective parents to understand if they are at risk of passing on an inherited genetic disorder to their offsprings.
When done before pregnancy it is advantageous since it enables the couple to perform research, seek resources and make an informed decision.
Couples are encouraged to consult a geneticist or genetic counselor before planning a pregnancy.
Genetic counseling is highly recommended along carrier screening as a genetic counselor can explain testing options and help interpret test results to make the right decisions.
It might take about a couple of weeks to get your results of carrier screening.
All individuals carry two copies of most genes (one from each of their parent).
A genetic carrier is any person who possesses a mutation in one copy of any gene.
While carriers do not have the disease linked to the mutation, they might pass it on to their offsprings.
For the most part, all individuals carry a gene for at least one genetic disease.
However, the concern is that if both parents have the same mutations.
Down Syndrome
Trisomy 18
Trisomy 13
Spina bifida
Fragile X Syndrome
Cystic Fibrosis
Spinal muscular atrophy
Thalassemia
Tay-Sachs disease
Getting a genetic test done before planning for pregnancy can tell you the odds of having a baby with any genetic disorder.
It is recommended that a couple should take it if in case either one of them has a higher risk of passing on certain diseases to their children.
Thanks to the advent of genetic testing, the number of people with genetic disorders like Tay-Sachs has gone way down!
However, for couples where neither of them is at high risk, they can take an opinion from their doctor or genetic counselor to make the decision.
Prenatal genetic testing identifies:
Risk of potential issues in an unborn child.
Congenital disabilities
Genetic disorders
Prenatal testing can identify women with a high risk of having a down syndrome child and cannot determine certainly if the fetus is affected or not.
There are diagnostic tests that are extremely accurate at prenatal screening for down syndrome.
While genetic screening tests have absolutely no risks of miscarriages, the diagnostic ones have a small (<1% chances) of miscarriages.
There are noninvasive prenatal genetic testing that can determine if your baby is at risk of developing Edwards syndrome or other trisomy disorders.
If in case the results indicate a high risk, your doctor might recommend specific diagnostic tests which might be more invasive but could find out if your baby has the disease or not.
Doctors recommend prenatal tests to look for signs that the baby is at risk for certain genetic disorders or congenital disabilities.
They particularly recommend prenatal genetic screening for women with the following criteria:
Age above 35
Previous history of a premature baby or a baby with a congenital disability
Genetic disorders running in the family of either parent
Medical conditions like high blood pressure, diabetes, autoimmune diseases, seizure disorders, and others.
Previous history of miscarriages or stillborn babies
Prior history of gestational diabetes
With different types of BRCA testing offered by many laboratories these days, the cost ranges from $475 to $4000, varying according to the laboratory that provides the test.
The moral and ethical issues regarding genetic testing have seen considerable debates.
There are two theories to be considered while answering ethical questions about genetic testing.
Utilitarian perspective is that moral decisions should be decided by calculating a burden/benefit ratio from the society point of view.
According to this, if there are many people at risk, they should be informed about it.
Also, family members at risk should be told in advance to reduce the intensity of pain via medical intervention, decrease the duration of symptoms, delay the onset of symptoms, and increase the quality of life.
Libertarian Perspective has a belief that personal autonomy has the highest moral value; implying that each person has his/her rights to make informed decisions.
According to this perspective, it is up to an individual to understand their disorder and make a choice about informing family members.
It is expected that individuals may consent to genetic testing not just for their good but also for the sake of family and society.
Also, genetic disorders are attached to social stigmatism. People diagnosed with genetic disorders could be discriminated and harassed by others.
A libertarian view is that every individual has the right to be happy and make their own choices without being influenced by doctors, counselors or other members of the society.
Ideally, there should be a balance between these two perspectives.
Thus, if a physician is trained in genetic counseling, ethics, and genetics, he can help the patient make a completely informed decision about genetic testing with regards to the rights of the patient along with those affected by the patient's choices.
Both patients and their healthcare providers should be aware of the relevant ethical, legal and social issues about genetic testing such as:
Communicating Test Results: While the results are being disclosed to people it is important to understand that the results will not be straight-forward. There may be potentially inconclusive results or risk estimates. Individuals need to understand the extent of the information actually received. The results containing any personal identifiers shouldn't be provided to any outside parties (employers, insurers, government agencies, etc) without the written consent of the patient.
Direct-to-Consumer (DTC) tests: These tests do not involve recommendation from a physician.
Duty to Disclosure: Per American Society of Human Genetics, disclosure to at-risk individuals is permissible if the following criteria are met:
Has At-risk relatives
Harm at a high probability, serious, imminent and anticipated
Preventable disease, medically accepted standards of treatment and screening being available
Damage from disclosure lower than the harm from failing
Genetic Discrimination: The fear of discrimination can impact an individual's decision to utilize genetic testing services. They also fear discrimination in employment, health insurance and if their genetic information might be used to stigmatize them. Healthcare providers should be sensitive to the fact that some groups may distrust the use of genetics as a health tool. The Genetic Information Nondiscrimination Act (GINA) prevents health insurers from denying coverage or adjusting premiums by genetic testing and prohibits employers from using such information to hire, fire or promote individuals. The law also limits employers to request, require or purchase an employee's genetic information.
Informed Consent- To ensure that individuals understand the risks & benefits of their healthcare choices like opting for genetic testing, informed consent is a part of the medical decision-making process. Parameters for informed consent include
Risks, limitations, benefits
Alternatives methods of diagnosis
Details of the testing process
Privacy/ confidentiality of test results
The voluntary nature of the test
Potential consequences related to the results- emotional, psychological reactions, impact on health, ramifications for the family members, treatment or prevention options
Privacy: The privacy of genetic information is a major concern for patients and to protect it and avoid its inclusions in one's medical records is generally preferred.
Psychosocial impact- Each person may respond in a different way to a genetic test result- be it negative or positive. Since there is no right or wrong response, doctors should refrain from judging them and help them understand how to proceed with available options. Referrals to genetic counselors, psychologist or social workers should be made as required.
Reproductive Issues- Since genetic testing procedures carry risks and benefits, parents should carefully consider and discuss these with their healthcare providers to take the right decision
Societal values: Questions about personal responsibilities, personal choices vs. genetic determinism and concepts of health and diseases can be raised. Health professionals should be respectful and sensitive to cultural & societal values and work together with the patient to define an appropriate course of action and follow-up care.
Test Validity: Since most genetic tests are offered as services and not approved by the FDA, the information should be shared with the patient as they consider whether the test is appropriate for them or not. Genetic tests should be ordered only from CLIA or government certified laboratories.
Males have one X chromosome and a Y chromosome, whereas females have two X chromosomes.
In X-Linked inherited diseases, a male with a mutation in a gene on the X chromosome gets the disease, but since they have only one X chromosome, the gene alteration just gets transmitted from female carriers to sons and not from male carriers.
This is because males transmit only their Y chromosome to their sons and do not pass on an X-linked recessive condition to their sons.
Typically females with a mutated gene in the X chromosome is said to be a ‘carrier’ for an X-linked condition, and a male with a mutated gene in the X chromosome gets affected with the condition.
Males with a mutation in a gene on the X Chromosome can transmit either the mutated X chromosome or a Y chromosome to his children.
If the child is a male, he would not be affected with the disease since he inherits only the Y chromosome from his father and an X chromosome from his mother.
And if the child is a girl, she might be a carrier or get affected by the disease since she gets the mutated X chromosome from the father.
No, it is females with one affected X chromosome who are carriers of hemophilia.
Sometimes these carriers can exhibit symptoms of the disease and pass on the affected X chromosome with the mutated clotting factor gene on to her offsprings.
The faulty gene responsible for color blindness is present only on the X chromosome.
If a woman has a single color blind gene, she is known as a ‘carrier’ but won't be color blind herself.
She will pass on her faulty X chromosome to her child- if it is a son, he will be color blind.
Thus, only females are carriers of this condition.
In genetics, the term ‘carrier’ refers to anyone who carries two different forms of a recessive gene.
An individual with one dominant and one recessive allele for a gene will have the dominant phenotype.
They are usually called “carriers” of the recessive allele and not that of the dominant allele.
Carriers of Sickel cell disease are at risk of having children with the disease.
However, only if both parents are carriers of the disease, your child has a 25% chance of not having it nor being a carrier and a 25% chance that the child will be born with the disease. Another 50% chance is that the child will be a carrier but won’t have the disease.
Thus if both parents are carriers of Sickle cell disease, it is essential to consult a genetic counselor to get the risks and options explained.
A carrier for sickle cell disease is a person who has one gene for sickle hemoglobin and another for normal hemoglobin.
While they do not face any symptoms or issues and lead healthy lives, they are likely to pass it on to their children.
No, it doesn’t. This is because they do not perform carrier testing for all inherited diseases and for those conditions that they do, they don’t report on all possible variants.
Most conditions included in the carrier status reports could be caused due to hundreds or thousand different genetic variants.
23andMe’s carrier status reports cover many variants but do not include all the possible variants associated with each condition.
Certain conditions occur more frequently in a particular ethnicity than others.
For instance, sickle cell anemia is most commonly reported in African descent, and Bloom syndrome among the Ashkenazi Jews.
Xcode Life’s Carrier Status Report provides information on more than 250 inherited genetic conditions.
Lynch Syndrome or Hereditary Non-Polyposis Colorectal Cancer (HPCC) is a type of a tumour that is inherited in an autosomal dominant manner and is associated with the predisposition to other cancer types.
This means that people who suffer from Lynch Syndrome are more predisposed to develop certain types of cancers including colorectal, uterine, endometrial, and ovarian cancers.
It is caused by an alteration in a set of genes called Mismatch Repair Genes.
Lynch Syndrome is a silent condition and never gives any prominent symptoms.
One of the first symptoms that indicate the presence of Lynch syndrome is the development of bowel or womb cancer.
This usually appears in people who are young. Other symptoms include:
However, these symptoms are general in nature and can appear with other conditions as well. Hence it is best to get them evaluated by your doctor.
The treatment options available to a person diagnosed with Lynch Syndrome depends on the age of the individual, current health condition, stage, and location of cancer and personal preferences.
Colon cancer in Lynch syndrome is treated in the same way as other colon cancer that develops without the presence of Lynch Syndrome.
However, during surgical removal of the cancerous part of the colon, more of the organ is removed than in case of normal colon cancer as the chances of recurrence in Lynch syndrome are higher.
Treatment for colon cancer in Lynch Syndrome includes surgery, chemotherapy, and radiation therapy.
In cases of uterine or ovarian cancers associated with Lynch syndrome, ovaries and the uterus are removed surgically to prevent the spread of cancer, and recurrence.
Sometimes the diagnosis of Lynch Syndrome could happen before the development of the associated cancer types.
They are called previvors and are advised to undergo screening tests for various cancer types that they stand a risk of developing.
Lynch Syndrome can be detected using a genetic test.
Using this method it is possible to detect the gene variants that influence Lynch syndrome and accordingly devise the next steps.
The test can determine if an individual is a carrier of a mutation that can be passed on in one of the genes that are associated with Lynch syndrome.
Today, testing is available for MLH1, MSH2, MSH6, PMS2, and EPCAM genes.
The other type of test is the tumour testing method that uses cells from cancerous tissues to determine if the individual has Lynch syndrome.
These tests include Microsatellite Instability Testing (MSI) and Immunohistochemistry Testing (IHC).
Please note: The lynch syndrome report has been temporarily discontinued for research and update. We will be putting out an announcement on the website once we relaunch it.
Colorectal cancer is one of the top 3 cancers in the USA and about 1,33,000 people are diagnosed with it each year.
However, uterine cancer is not as common as colorectal cancer.
Only 55,000 cases are diagnosed each year in the USA and women have a 3% chance of developing uterine cancer in their lifetime.
As we saw earlier, Lynch Syndrome is due to several mismatch repair genes.
These are MSH2 and MSH6 on chromosome 2, MLH1 on chromosome 3, MSH3 on chromosome 5 and PMS2 on chromosome 7.
Furthermore, mutations in any one of these genes cause an increased risk of developing colorectal cancer and other cancers.
We know by now that individuals with Lynch syndrome have a higher risk of developing colon and womb cancers.
Additionally, other cancers that these individuals are predisposed to include breast, bowel, prostate, liver, urinary tract, ovarian cancers, digestive, gastric, pyloric gland and duodenal adenomas.
Lynch syndrome by itself is not cancerous.
However, it predisposes an individual to various types of cancers mentioned above.
One of the factors that increase an individual’s risk of developing pancreatic cancer is genetic syndromes (that cause as many as 10% of the pancreatic cancers).
One such condition is the link between Lynch Syndrome and the risk of colon cancer.
So, in a way, Lynch syndrome increases one’s risk of developing both colon and pancreatic cancers.
The common risk factors for pancreatic cancer include:
Lynch syndrome is a hereditary condition, which means that the genes responsible for the condition are passed on from the parents to the offsprings.
With Lynch syndrome, there is a 50% chance that an individual passes them on to his/her offsprings.
Therefore, this means that Lynch syndrome does not skip a generation and affects males and females equally.
Lynch Syndrome is inherited in an autosomal dominant manner, which means that the offsprings with even one mutated gene stand a chance to develop the condition.
There are a few genes like the MLH1, MSH2, MSH6, and PMS2 that are responsible for the repair of errors that occur when DNA duplication occurs in the process of cell division.
Therefore, mutations in these genes lead to the development of Lynch syndrome.
Handpicked For You: Best DNA Raw Data Analysis Tools For Information On Gene Variants
Familial history of cancers often puts an individual at risk of developing them as well.
The same holds true for colorectal and endometrial cancers, that are predominantly seen in case of Lynch syndrome.
If you have a history of colorectal cancer in the close or far family, it is best to speak with your doctor or a genetic counsellor.
They will review your family history and determine whether you have Lynch syndrome or other associated symptoms.
They will advise you if you need genetic testing or not.
But, you should know that while genetic testing will help detect any gene mutations, they are not absolutely perfect and might not work for a small fraction of people.
Learn More About Lynch Syndrome In Xcode Life's Carrier Status Report
It has been studied at the University of Texas MD Anderson Cancer centre that even before colorectal or colon cancer develops, the immune system activation takes place that gives rise to colon polyps in patients with Lynch Syndrome.
Moreover, the study also suggested that immune activation takes place before the gene mutations actually occur.
Non-polyposis in HPCC or Hereditary Non-polyposis Colorectal Cancer also called Lynch syndrome, meaning that colorectal cancer occurs when there are very few numbers of polyps or sometimes no polyps at all.
Furthermore, in families who have a history of HPCC, colon cancer may occur or begin to occur on the right side of the colon.
Like in most disease conditions, including cancers of various types, diet plays a significant role in their prevention and development.
When it comes to colorectal cancer, a diet low in fibre, high in red meat and very few vegetables increases the risk of developing the condition.
Well, one needs to be careful about what he/she is consuming in the daily diet.
Avoiding refined sugar, on which cancer cells and other cells feed on, is the primary thing to do.
Moreover, foods to strictly avoid include red meat of all types.
In fact, it is best to go vegetarian or vegan and include lots of fibres from grains, vegetables and fruits, and lots of antioxidants in the diet to reduce the risk of developing colorectal cancer, especially when detected with Lynch syndrome.
Lynch syndrome is not an autoimmune disease but patients with autoimmune diseases like Sjogren's syndrome, Rheumatoid arthritis or Systemic Lupus Erythematosus (SLE) have an increased risk of developing malignancies, especially lymphoid malignancies.
In fact, it is a challenge to treat patients with rheumatoid arthritis as some medications used to treat a severe form of the condition need to be carefully used in patients with a history of malignancy.
Lynch syndrome is not a rare disease.
Moreover, it accounts for 2-4% of all colorectal cancer cases and 2.5% of endometrial cancer cases.
Genetic testing is becoming increasingly popular and important to determine one’s predisposition or risk to developing many hereditary, genetic and metabolic conditions.
Genetic testing for colon cancer syndromes like Lynch syndrome costs anything between $400 to $5000.
Additionally, the test results can take about a few days to a few months to arrive and are often suggested by genetic counsellors in specific cases.
Its health predisposition tests help in determining an individual’s tendency to develop certain conditions like Type 2 diabetes, Celiac disease, BRCA1 and BRCA2 (cancer-related genes), Late-onset Alzheimer's disease, Parkinson’s disease, etc.
23andMe offers carrier tests for over 40 diseases that help couples understand their inherited conditions that can pass on to their future child.
Moreover, this test helps detect conditions like sickle cell anaemia, cystic fibrosis, Lynch syndrome to name a few.
23andMe also helps evaluate how one’s genes play a role in the wellness and general health of the individual.
23andMe tests assess the genetic health risks for conditions like Celiac disease, Alzheimer’s disease, and Parkinson’s disease.
Also read: Differences Between Health Reports From 23andMe and Xcode Life
23andMe does not include diagnostic tests.
All the tests it provides – carrier status, health predisposition, wellness, and trait reports are all suggestive and indicative.
They, at no point, are definitive or diagnostic in nature.
Furthermore, using the genetic tests offered by 23andMe, one can understand what risks he/she has for developing a condition before the condition actually sets in.
This helps to prevent the condition by early intervention and treatment.
What is cholesterol? What role does it play in our body?
Cholesterol is a type of fat with a waxy texture. It plays a vital role in maintaining the structure of every cell in our body.
While the liver produces cholesterol in our body, we also obtain cholesterol from the different foods we eat such as meat, butter, cheese, and many others.
Cholesterol is a part of the cell membrane of every cell in our body.
It controls the flow of substances into and out of the cells and aids the normal functioning of organs.
Cholesterol plays an important role in the synthesis of vitamin D and sterol hormones in the body.
It is also essential in order for our body to synthesize bile acids that aid in food digestion
The food we eat is digested, and the cholesterol consumed eventually enters the bloodstream.
Cholesterol cannot travel through the blood on its own- free cholesterol in blood would look like a drop of oil in water and would be unable to move very far.
As a workaround, the body creates little fat-pockets called lipoproteins. These lipoproteins carry the cholesterol to different cells in our body.
High-density lipoproteins (HDL) and low-density lipoproteins (LDL). High-density lipoproteins (HDL) is the "good" lipoprotein. It transports cholesterol from the artery to the liver.
On the other hand, low-density lipoprotein (LDL) also transports cholesterol, but too much of it can have adverse effects on the body.
When we consume food rich in cholesterol or if the body is unable to transport cholesterol to the cells efficiently, it begins to accumulate in the blood vessels.
When there is too much cholesterol– especially LDL– in the bloodstream, it can build up on the walls of the arteries.
As these clumps of “bad cholesterol” grow bigger, they eventually end up clogging the arteries.
This leads to the formation of plaques, and it hampers the flow of blood to the heart.
If the condition worsens, it could lead to heart disease.
The plaque may also form within the arteries that supply blood to the brain and cause a stroke.
Very high levels of cholesterol (LDL specifically) in the blood is called hypercholesterolemia.
Lifestyle factors such as an unhealthy diet, a sedentary lifestyle, smoking, and obesity typically cause hypercholesterolemia. However, some other factors out of your control such as your genetic makeup also influence your predisposition to develop hypercholesterolemia.
The Low-density lipoprotein reception (LDLR) gene on chromosome 19 controls the production of a protein called LDL-receptor. When we have normal levels of LDL in our bloodstream, the LDL receptor proteins bind to the LDL molecules and transport the LDL to the cells with the help of many other proteins.
This ensures that the LDL is transported into the cells and does not accumulate in the bloodstream to cause any damage to the arteries.
One in 500 people may have a mutation (or an alteration) on the LDLR gene that controls the clearance of LDL from the bloodstream.
In such cases, the number of LDL receptors in the blood will be significantly reduced.
This makes it harder for the body to clear LDL from the bloodstream.
This results in high levels of LDL and total cholesterol in the blood.
This condition of hypercholesterolemia resulting from a genetic mutation is called familial hypercholesterolemia.
Since familial hypercholesterolemia occurs from a genetic mutation, we can inherit it from our parents and also pass it on the next generation.
If the parent has familial hypercholesterolemia, there is a 50% chance that this mutation is passed on to their children.
If a person inherits one copy of the mutated gene from their parents, they are considered to have familial hypercholesterolemia.
This condition is called heterozygous familial hypercholesterolemia.
In some even rarer cases, a person may inherit this mutated gene from both parents (this means that both parents have familial hypercholesterolemia).
This is a more severe case called homozygous familial hypercholesterolemia.
In this case, all biological children of this person will definitely have familial hypercholesterolemia.
Best Raw Data Analysis Tools To Analyze Your Familial Hypercholesterolemia Variants
In most countries, familial hypercholesterolemia occurs in about 1 in 500 people. However, it is reported to occur more frequently among the French Canadians, Afrikaners in South Africa, Finns, and Lebanese.
If you are under the age of 60, the following symptoms would suggest that you may have familial hypercholesterolemia.
Yes. When cholesterol deposits build up as plaque in the major blood vessels that supply blood to the heart, it makes it more difficult for the blood to flow through these blood vessels.
This increases the blood pressure reading and is a risk factor for heart disease.
Your physician may suspect that you have familial hypercholesterolemia during a physical examination based on some symptoms. They may also request for additional laboratory tests such as blood tests for cholesterol levels and cardiac function tests.
Additionally, your physician could also prescribe genetic testing to identify if there is a mutation in the LDLR gene.
Stay Ahead Of Familial Hypercholesterolemia: Know You Gene Variants Now!
Familial hypercholesterolemia cannot be cured, but it can be treated to keep cholesterol levels low. Treatment would typically include:
Familial hypercholesterolemia is the cause of an early onset coronary artery disease (i.e. heart disease before the age of 55 years) in about 10 percent of people. If left untreated, familial hypercholesterolemia can reduce the life expectancy of a person by 15-30 years.
Hence it is essential for someone with familial hypercholesterolemia to not only seek medical care right away but to adhere to their treatment regimen.
While our genetic makeup determines whether or not we have Familial hypercholesterolemia based on the presence of a mutated LDLR gene.
However, you can seek medical treatment to control your cholesterol level.
Additionally, you must also moderate lifestyle factors such as diet, smoking, and alcohol consumption habits, and physical activity to keep your cholesterol levels in check.
https://www.heartfoundation.org.au/healthy-eating/food-and-nutrition/fats-and-cholesterol
https://www.genome.gov/25520184/learning-about-familial-hypercholesterolemia/
https://medlineplus.gov/ency/article/000392.htm
https://www.genome.gov/25520184/learning-about-familial-hypercholesterolemia/#al-3
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Dietary fats are important for energy and for cellular growth, however, the type of fat consumed is key.
One of the popular ‘dietary advice’ is that saturated oils are bad for health and that they should be substituted instead by polyunsaturated fatty acids (PUFA).
However, this may not be true for everyone.
Every once in a while, there comes a new study that purports to debunk long-held beliefs, such as the one above.
How we respond to sunflower oil in our diet may depend on the genetic variants we carry.
Does that mean sunflower oil may be bad oil for some?
More about sunflower oil
Sunflower oil is made from sunflower seeds and has has been shown to reduce LDL cholesterol and constipation.
Its benefits have, however, been more as a massage oil for helping the skin heal wounds, for psoriasis and for arthritis.
The current scientific study by The University of Finland focuses on the effect of using sunflower oil as cooking oil, stratifying the effects based on FADS1 gene variants.
FADS1 gene
FADS1 gene is associated with fatty acid metabolism and also in glucose metabolism.
The diet of an individual plays an important role in the concentration of the various fatty acids in the body.
Linoleic acid is the most common polyunsaturated fatty acid is found in plant-based oils, nuts, and seeds.
You may have come across studies that have shown how a high intake of linoleic acid helped in lowering risk of cardiovascular disease and type 2 diabetes while another study may have pointed out its association with risk of low-grade inflammation.
This study helps shed new light by stating that these contradictions may be due to genetic differences.
This study opted for a unique yet preferable research setting, where the study participants were stratified based on their genotypes i.e based on their FADS1 gene variant.
This was done to find out if there was an association between FADS1 gene variant and the effect of linoleic acid on fasting glucose, on serum fatty acid composition, on C- reactive protein (CRP- a biomarker for inflammation) and insulin levels.
1,300 middle-aged men were included in the study that studied the metabolic effects, while 60 participants were included in the study on the effect of a diet based on genotype.
The participants consumed 30-50 ml of sunflower oil (linoleic acid) every day for four weeks.
The study found that the effects of linoleic acid were significantly associated with FADS1 gene variant.
This would mean that your genetic variant could determine if the linoleic acid supplement could effectively lower your fasting glucose levels and if increased intake of linoleic acid would increase or decrease your CRP levels.
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Knockdown mice study
One of the ways scientists determine the effect of a gene on health is to reduce the expression of the gene from mice and then study the effect that it causes.
Mice which had the FADS1 gene expression reduced were given a diet rich in linoleic acid and they showed better glucose metabolism but they also exhibited hepatic inflammation.
This confirms the results of the sunflower oil study.
What does all this mean to you?
If you have the CC genotype, a high intake of sunflower oil may lower fasting glucose levels.
However, there is an association with higher CRP (biomarker or inflammation) on high sunflower oil intake, which could mean that you run the risk of low-grade inflammation.
Low-grade inflammation is an important factor in progression to chronic diseases. Therefore, limiting sunflower oil may be better, based on this study.
If you have the TT genotype, a high intake of sunflower oil is not associated with a risk of inflammation.
Therefore, based on this study, you could switch to sunflower oil or continue to include it in your diet, if you are already doing so!
However, please note that Omega 6 which is predominantly found in vegetable and seed oils needs to be balanced with Omega 3 intake, with an optimal ratio between omega 3: omega 6 being around 1:2.
If you have the CT genotype, a high intake of sunflower oil is not associated with a risk of inflammation.
Therefore, based on this study, you could switch to sunflower oil or continue to include it in your diet, if you are already doing so!
However, please note that Omega 6 which is predominantly found in vegetable and seed oils needs to be balanced with Omega 3 intake, with an optimal ratio between omega 3: omega 6 being around 1:2.
Wondering if sunflower oil (PUFA) could increase your risk of weight gain?
Find out from Xcode Life nutrition genetics report, which analyses your genetic variants for response to macronutrients like carbohydrates, proteins, saturated fats, MUFA and PUFA in the perspective of weight gain.
There are more than 30 traits covered in the report including gluten sensitivity, a risk for alcohol flush, food preference and more.
If you find yourself lying awake in bed at night unable to sleep and the usual fixes like counting sheep or downing a warm glass of milk don’t seem to help, don’t take it lightly—it could be insomnia.
A 23andMe sleep study analyzed the genetics associated with sleeplessness and found that insomnia shares more genetic similarities with mental illness than with other sleep disorders.
This is not the first time that these scientists have shared such insights on sleep.
Another important determinant of a good night’s sleep- deep sleep, 23andme scientists revealed, also shares a strong genetic basis.
However, this is the first time a sleep trait has been linked to mental illness, making it imperative to find out more about your insomnia genetics.
Do you feel tired all day and alert all night? Is your sleeplessness less to do with monsters in the dark and more to do with underlying health conditions?
Not getting a good night’s sleep may sound trivial, but it has more serious and further reaching consequences than just a lethargic morning and a cranky, coffee-fuelled workday.
Insomnia has been linked to metabolic syndrome and can make sufferers more vulnerable to becoming overweight and developing diabetes and heart disease.
Insomnia is the most common sleep disorder and is considered the second-most common mental disorder.
About 30 percent of adults report short term insomnia at some point in their lives, while about 10 percent report suffers from chronic insomnia.
In a study involving over 1.3 million test subjects who volunteered their DNA samples, researchers found that no single gene contributed to this disorder, but that it was complex combination of effects from multiple genes that predisposed a person to develop insomnia.
Researchers from the Netherlands and Amsterdam collaborated with scientists from genetic testing company 23andMe to narrow down 202 gene markers involved in insomnia.
They were also able to identify the specific type of brain cells and tissues involved in striatal medium spiny neurons, hypothalamic neurons, and claustrum pyramidal neurons.
Some of which have been linked to reward processing, sleep, and arousal in animals, but have never before been genetically linked to insomnia in humans.
Hand-Picked article for you: Have Your 23andMe Raw Data? Use It To Get 500+ Health-Realted Genetic Traits!
The most interesting finding in this study, however, was the large genetic similarity between insomnia and psychiatric conditions such as anxiety, major depressive disorder, and neuroticism.
Despite being inherently a sleep disorder, insomnia had very little genetic material in common with other sleep traits like daytime dozing, snoring, excessive napping and ‘morningness’, the trait that makes some lucky individuals perky and chirpy early in the morning.
This discovery may help researchers understand the mechanism of insomnia better and help sleep specialists devise new methods and medications to treat the disorder, possibly helping patients stave off the more serious health issues that develop due to insomnia.
Moreover, understanding your risk of insomnia will help in being self- aware and to find solutions, thereby, lowering the risk of associated conditions.
The 23andme deep sleep report discusses the variant of the deep sleep gene you have, helping you understand your sleep better.
Xcode life sleep report has over 10 traits associated with sleep including insomnia, sleep quality, sleep duration and more.
Are you a “night owl”- wide awake and active till way past midnight, but somehow still manage to wake up early to get to work? Or are you that person who is early to bed but late to rise, because your body needs at least 10 hours of sleep to function the next day? Well, either way, you may find some clues from your genes.
Scientists have identified 76 new gene variants that are associated with the amount of sleep you get, throwing new light on the mechanisms of the sleep-wake control centers of the brain.
This study conducted by researchers from Massachusetts General Hospital (MGH) and the University of Exeter Medical School is the largest of its kind, including more than 446,000 participants in the U.K. who self-reported the amount of sleep they typically received. As a result, they found that genes are responsible for 10-40% variation in an individual’s sleep duration.
While 7-8 hours of sleep per night is considered optimum, 6 hours or less is considered too little sleep and more than 9 hours, too much.
It is known that too much and too little sleep are harmful and can lead to chronic diseases.
This study also found genetic links associated with poor sleep patterns and conditions like depression, higher levels of body fat and fewer years of schooling!
In order to probe these associations further, scientists conducted separate gene association studies on groups of people who reported lower than average sleep hours and longer sleep duration.
There were some interesting findings-- short sleep duration was genetically associated with traits like insomnia and smoking, while longer sleep duration was associated with schizophrenia, type-2 diabetes, and coronary artery disease.
Not relying on data from questionnaires alone, participants in the study were asked to wear accelerometers (motion-detecting devices like Fitbit) for up to a week before undergoing genetic testing for the 78 sleep-duration associated gene variants.
Investigators were able to objectively associate these genetic regions with not just the number of hours of sleep that the individual got, but also sleep quality, instances of waking up in the night and daytime inactivity.
Interestingly, the gene regions associated with sleep duration were different from those associated with insomnia or sleep chronotype, identified in previous studies.
This study helps in understanding each person’s natural optimal sleep duration for a refreshing sleep.
Also Read: Have Your 23andMe Raw Data? Use It To Get 500+ Health-Realted Genetic Traits!
