Last updated date: 13-Mar-2023
Originally Written in English
Genetic counselors work as members of a healthcare team, providing information and support to families who are dealing with or at risk of genetic disorders. Other health care professionals, patients, and the general public provide a central source of genetic condition information. In delivering competent genetic services, genetic counselors play a significant role. They are educated to provide families and patients with frequently complex and difficult-to-understand information on genetic risks, testing, and diagnosis, as well as counseling and referrals to educational and support programs.
What is Genetic Counselling?
Individuals and families diagnosed with or at risk of genetic diseases get genetic counseling to help them understand and adjust to the medical, psychological, and familial consequences of hereditary contributions to disease. Individuals affected with, or at risk for, a genetic or hereditary condition are informed about the implications of the disorder, the likelihood of suffering from or passing it to their offspring, and the unique value of treating or preventing the abnormality or disease in concern. In the case of common diseases, genetic counseling is frequently provided by the family physician, pediatrician, or obstetrician. With the understanding that hundreds of disorders have a significant genetic component, counseling is increasingly being done in specialist clinics that also provide the laboratory testing techniques that you hear so much about these days.
Approximately 2-3 percent of babies are born with congenital abnormalities, most of which have a genetic component. And, if one examines the causes of disease in people under the age of 25, at least 5% of all people will suffer from an abnormality or disease with a significant hereditary component by maturity. As a result, understanding and controlling genetic abnormalities is a major public health concern, especially in light of the drop in infectious disease mortality and morbidity.
Genetic Counselling Aspects
Giving genetic counseling involves four aspects:
- Reaching a definitive diagnosis. for both health care professionals and families, this is typically the most challenging, frustrating, and time-consuming element of the process (who are more concerned with the care of their affected relative, than with the name of his or her disorder). Counseling is, at best, partial and imprecise without a proper diagnosis.
- Risk assessment. The likelihood of developing the condition and/or passing it on to children.
- Practical aid. This could involve referring them to doctors for specialized tests or referring them to speech or educational therapists. It frequently entails coordinating prenatal and other diagnostic tests as well.
- Supportive role. This is as least as crucial as the diagnostic issue because the vast majority of genetic disorders are neither curable nor even treatable. Although the genetic counselor will not be able to provide daily counseling to the family, he or she should be able to direct them to the health specialists who can better serve them in this role. Understanding and learning to live with a genetic condition is especially challenging when reproductive choices are involved, and feelings of guilt can span generations and cause family rifts exactly when family unity is most needed.
Genetic Disorders Types
Hereditary does not always imply genetics. The second word simply means that the genetic material has one or more mutations that are the cause of the condition on a chromosomal or gene level. Once a patient has a mutation, especially if it is constitutional (meaning it affects all cells), it might be passed and so become a hereditary condition.
There are four types of genetic disorders:
- Chromosomal abnormalities. It afflicts roughly 1 in every 200 live-born children and 1 in every 500 adults. Chromosome number abnormalities are seldom inherited, however, affected individuals who reproduce may pass on the extra chromosome to their children. Structural abnormalities, such as translocations, in which two chromosomes interchange regions, may have little or no effect on carriers, but may increase the risk of abortion and infertility.
- Monogenic (Mendelian) inheritance. It is caused by single-gene mutations at certain gene loci. We have between 50 and 100 thousand distinct genes, with monogenic disorders documented for several thousand of them. Within the first two decades, about 1 out of 300 people will have a monogenic disease, but this number might be as high as 1% if the lifelong risk of developing a monogenic disorder is taken into account. In monogenic disorders caused by nuclear genetic makeup, there are four types of transmission: autosomal dominant (one mutated gene of the pair is enough to cause the disease), autosomal recessive (both alleles must be abnormal to cause the expression), and X-linked, which includes recessive (theoretically, only males suffer, because they are hemizygous for the X chromosome) and, less commonly, X-linked dominant gene (males more severely affected than females). A few genes related to sex determination and fertility have been identified on the Y chromosome, which can only be passed down from father to XY offspring.
- Polygenic or multifactorial disorders. Although this causation is not as genetic as monogenic and chromosomal diseases, it is responsible for the majority of abnormalities and prevalent familial disorders. Polygenic means that the disorder is caused by the interaction of multiple separate genes, each slightly changed. Multifactorial causation states that the pathology is caused by both genetic and non-genetic (environmental, either prenatal or postnatal) causes. Approximately 5-10% of the population will be affected by an abnormality or a disorder in which hereditary factors play a significant role.
- Mitochondrial disorders. A new kind of inheritance originating from abnormalities in the mitochondrial genome has been discovered in recent years. Hundreds or thousands of mitochondria are found in each cell, each with one or more circular chromosomes. The symptoms vary according to the tissues affected and the percentage of mitochondria mutated, but the central nervous system and muscle are the first to be affected due to their high energy requirements. It's still unclear how common mitochondrial abnormalities are in human disease. The mutation occurs de novo in the diseased individual in many cases, although hereditary transmission is completely maternal because the mitochondria in a fertilized egg come only from the maternal germline.
Who Seeks Genetic Counselling?
Patients can either self-refer or be sent by a physician to most genetics’ sections. Nowadays, genetics has not progressed to the point where couples without a specific family history or a higher risk of a genetic condition for another reason can come for genetic screening. Preconception or prenatal screening for a variety of disorders will most likely become available to the general public in the not-too-distant future. However, only a few dozen of our 55,000-100,000 individual genes have been identified and their mutations specified for the time being. Any of these tests necessitates both technical expertise and significant time and financial effort. The six categories of reasons for obtaining genetic counseling are as follows:
- The person (typically wanting to have a parent) develops a hereditary or potentially genetic condition. This could be a (very mild) chromosomal disorder, a single gene condition (inherited in a dominant, recessive, or X-linked form), or a multifactorial disorder, reflecting the interaction of a genetic predisposition with unfavorable environmental conditions (for example, diabetes or epilepsy).
- A close relative has a genetic condition, and the person seeking advice is concerned about either his or her own chance of having the disease or the likelihood that his offspring may be affected.
- Because of his or her ethnic background, the individual is at a higher hereditary risk for a specific genetic condition. Each population has one or more genetic conditions that are particularly common within it, such as cystic fibrosis in white Europeans and sickle cell anemia in African and Mediterranean ethnicities, which are often passed as autosomal recessive characteristics. Couples that are consanguineous (close relatives) may face a similar situation, albeit there is no way of knowing whether specific genes or diseases are involved unless there is a positive family history for a specific disorder.
- The individual or couple is experiencing reproductive issues, such as infertility or recurrent miscarriage. Such issues could be caused by hereditary factors, notably chromosomal abnormalities. The person may be referred for a laboratory diagnostic test first, with counseling varying significantly based on the results of the tests.
- The couple has already had a kid or fetus with a genetic disease or deformity. In this case, the particular diagnosis may or may not be recognized, and the probability of recurrence might range from less than 1% to 50%.
- For reasons such as advanced parental ages, the couple seeks prenatal diagnosis counseling. Given their greater chance of carrying a child with a chromosomal defect, women aged 35 and up should be considered for amniocentesis or choriocentesis. Counseling sessions for older parents or those seeking prenatal diagnosis due to concern (for example, close contact with a disabled person) are designed to provide information about the benefits and hazards of prenatal diagnostic techniques.
In all of these cases, genetic counseling should be as objective and non-directive as possible. The purpose is never to make a decision for the family, whose family, social, moral, and religious circumstances are not the same as the counselors, but to offer them objective facts that will enable them to make their own reasoned decisions.
What Information is Sought in Genetic Counselling?
Unless a precise diagnosis has already been established, the first and most important priority is to determine the nature of the condition, if at all possible. If and when this is performed, the geneticist must frequently review the literature as well as draw on his own experience to provide the most accurate explanation of the problem to consultants. The natural history of the genetic condition, which includes prognosis and discussion of possible treatments as well as practical instructions for dealing with these, is of fundamental importance to the family. Even if it is not a primary concern for people seeking counseling for a newly born kid, the issue of recurrence risks, as well as the possibility of prenatal diagnosis if wanted by the family, must be discussed rapidly. This is a challenging job in and of itself, because necessary knowledge of a disorder or diagnostic approach may be limited, and couples may directly ask the counselor for directive counsel.
Genetic Counselling Steps
It is ideal for a geneticist to gather and analyze medical documents in advance, as well as to review modern literature on the problem to be managed, in order to counsel a given parent more successfully. The following are the steps to take once a family arrives at a genetic center, depending on whether a particular diagnosis has been established:
- Gathering a thorough family history from both sides of the family, even if counseling is being sought for a dominant disease affecting one parent. It is not uncommon for other antecedents to emerge during the course of such a history, which should be discussed as well.
- An evaluation of medical and/or pregnancy histories is particularly relevant when a diagnosis has not yet been made, but it also aids geneticists in learning more about the causes and natural histories of certain diseases.
- A physical examination of the affected individual, as well as other family members, is frequently required.
- Medical and/or lab tests may be recommended. If a diagnosis has not been made, these often include chromosomal analysis and, if the identity of the gene presumed to be involved is known, DNA analysis. X-ray or ultrasound studies, as well as numerous biochemical tests, are also frequently recommended. Medical tests to assess health risks associated with the disease can be established if a diagnosis is made.
- Genetic counseling is only available at the completion of this procedure.
Over the last 25 years, the approach to genetic counseling has evolved tremendously. Many illnesses can be identified because their genetic or chromosomal origin is recognized, rather than being based solely on clinical observations. The increased availability of laboratory tests enables for more accurate diagnosis and, in some cases, allows for pre-symptomatic or prenatal diagnosis for family members who prefer it. However, it should not be forgotten that the availability of such testing raises difficulties to address psychological and ethical issues. As a result, a specialization in medical genetics has evolved that studies the individual's and society's means and methods for resolving such issues.
In a number of European regions, as in the United States and Canada a few years ago through their national Boards of Medical Genetics, the training of professionals competent to provide genetic counselling has been standardized. Medical geneticists with post-graduate training depend significantly on cytogeneticists and molecular geneticists for diagnosis, as well as genetics associates (master's degree geneticists and nurse experts) and Ph.D. medical geneticists to help with the initial work-up and parental follow-up. As genetics has evolved into a distinct specialty, training programs for healthcare professionals at all levels have grown. The majority of training takes place in medical genetics departments at universities.
Services Offered by Genetic Counselling
Close relationships with hospital departments such as pediatrics and obstetrics, as well as access to professional diagnostic services and medical library resources, are required to provide both diagnostic counselling and follow-up services. However, a number of services are better provided at a single location:
- Genetic counseling and clinical diagnosis
- Chromosomal analysis (both prenatal and postnatal diagnosis)
- Extracting and storing DNA.
- DNA testing
- Services for prenatal diagnosis
Prenatal genetics refers to services provided to women during or before pregnancy.
Referral to genetic counseling in the preconception or prenatal setting may have general indications. among them, but not limited to:
- Maternal age (at the time of delivery, 35 years or older)
- Advanced paternal age
- Anomalies discovered by ultrasonography (e.g., increased nuchal translucency measures) in a current pregnancy
- An abnormal genetic screening test during a current pregnancy
- Currently pregnant and concerned about maternal exposures to pharmaceuticals, radiation, drugs, alcohol, or infections
- Consanguineous marriage (cousins or blood relatives)
- A hereditary genetic disease or chromosomal abnormalities in the family
- Screening for recessive and/or X-linked illnesses in genetic carriers
- Previous experience with a child who has a congenital defect, developmental problems, or other genetic problem
- Infertility history, multiple unexplained pregnancy losses, or unexplained infant deaths
- Single gene abnormality molecular test
Prenatal genetic counseling can aid in the decision-making step by guiding patients through examples of what others have done in comparable situations and their reasoning for doing so. Patients' decisions are influenced by a variety of factors, including the timing of testing, the accuracy of the information supplied by tests, and the risks and benefits of the tests. This conversation allows patients to put knowledge and circumstances into their own lives and values. They can opt for non-invasive screening (such as ultrasound, triple screening, or cell-free fetal DNA screening) or invasive diagnostic tests (amniocentesis or chorionic villus sampling). Invasive diagnostic tests have a minor chance of miscarriage, but they yield more accurate results. Testing is available to determine whether or not a certain genetic issue or chromosomal abnormality exists.
The fetus is surrounded by amniotic fluid, which is similar to water, during pregnancy. Live fetal cells and other components, such as alpha-fetoprotein (AFP), are found in amniotic fluid. Before your kid is born, these things provide crucial information about his or her health.
Amniocentesis is a prenatal test that involves extracting a small volume of amniotic fluid from the sac around the fetus. Under ultrasound supervision, a small sample of amniotic fluid (less than one ounce) is retrieved using a thin needle injected into the womb through the abdomen. After that, the fluid is transferred to a laboratory for testing. Depending on the genetic risk and test indication, many tests can be done on an amniotic fluid sample.
Although amniocentesis cannot detect all birth malformations, it can be used to detect the following problems if the parents are genetically predisposed:
- Down syndrome
- Sickle cell anemia
- Cystic fibrosis
- Muscular Dystrophy
- Tay-Sachs and related disorders
Spina bifida and anencephaly are examples of neural tube defects (diseases in which the brain and spinal column do not develop normally).
Because ultrasonography is done at the same time as amniocentesis, it can discover congenital problems that amniocentesis cannot (such as cleft palate, cleft lip, club foot, or heart defects). However, there are some congenital abnormalities that neither amniocentesis nor ultrasonography can detect.
You can ask to find out the baby's gender during an amniocentesis; amniocentesis is the most accurate procedure to identify the baby's gender before birth. However, an earlier ultrasound or genetic testing may have revealed the gender of the baby.
Genetic Test Carried Out on Children Under 15 Years Old
Genetic tests come in a variety of forms. Some study just a few genes, while others study the entire chromosome. Some explore unique proteins known as enzymes. Families are helped in selecting the best test by doctors and genetic counselors. Depending on the test, doctors can determine whether a patient is ill, at risk for illness, or a carrier of illness. Despite not having the disease, a carrier can transmit the altered gene to their offspring. If the genetic changes responsible for an illness are identified, genetic testing is typically possible. Testing can be done for:
- Cystic fibrosis
- Tay-Sachs syndrome
- Sickle cell disease
- Down Syndrome
- Spina bifida
- Turner syndrome
- Von Willebrand disease
- Duchenne muscular dystrophy
In some circumstances, it can also indicate a person's response to specific medications or whether they are more likely to develop certain cancers.
Genetic Counselling Salary
Genetic Counselors made an average salary of $85,500 in 2020. The best-paid 25% made $103,500 that year, while the lowest-paid 25% made $74,000.
Genetic counselling is a communication process aimed at assisting individuals, couples, and families in comprehending and adapting to the medical, psychological, familial, and reproductive consequences of the genetic contribution to certain health disorders.
This method incorporates the following: family and medical histories are analyzed to determine the likelihood of disease onset or recurrence, education about the condition's natural history, inheritance pattern, testing, management, prevention, services for assistance, and research, counseling to help people make better decisions based on their risk estimate, family goals, and ethical and religious beliefs, and support for an affected family member's best potential adaptation to the disorder and/or the danger of recurrence of the disorder.