Genetic counseling
Encyclopedia
Genetic counseling or traveling (British English) is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning
. This complex process can be separated into diagnostic (the actual estimation of risk) and supportive aspects.
(NSGC) officially defines genetic counseling as the process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease. This process integrates:
A genetic counselor is an expert with a Master of Science
degree in genetic counseling. In the United States they are certified by the American Board of Genetic Counseling.http://www.abgc.net Most enter the field from a variety of disciplines, including biology
, genetics
, nursing
, psychology
, public health
and social work
. Genetic counselors should be expert educators, skilled in translating the complex language of genomic medicine into terms that are easy to understand.
Genetic counselors work as members of a health care team and act as a patient advocate as well as a genetic resource to physicians. Genetic counselors provide information and support to families who have members with birth defects or genetic disorder
s, and to families who may be at risk for a variety of inherited conditions. They identify families at risk, investigate the problems present in the family, interpret information about the disorder, analyze inheritance patterns and risks of recurrence, and review available genetic testing
options with the family.
Genetic counselors are present at high risk or specialty prenatal clinics that offer prenatal diagnosis
, pediatric care centers, and adult genetic centers. Genetic counseling can occur before conception (i.e. when one or two of the parents are carriers of a certain trait) through to adulthood (for adult onset genetic conditions, such as Huntington's disease
or hereditary cancer
syndromes).
A woman, if pregnant, may be referred for genetic counseling if a risk is discovered through prenatal testing (screening or diagnosis). Some clients are notified of having a higher individual risk for chromosomal abnormalities or birth defects. Testing enables women and couples to make a decision as to whether or not to continue with their pregnancy, and helps provide information that can be used to prepare for the birth of a child with medical issues.
A person may also undergo genetic counseling after the birth of a child with a genetic condition. In these instances, the genetic counselor explains the condition to the patient along with recurrence risks in future children. In all cases of a positive family history for a condition, the genetic counselor can evaluate risks, recurrence and explain the condition itself.
. Some diseases can be inherited from one parent, such as Huntington’s disease. Other genetic disorders are the cause of an error or mutation occurring during the cell division process (trisomy
). Testing can reveal conditions that are easily treatable as long as they are detected (Phenylketonuria or PKU
). Results from genetic testing may also reveal:
Each individual considers their family needs, social setting, cultural background, and religious beliefs when interpreting their risk. Clients must evaluate their reasoning to continue with testing at all. Counselors are present to put all the possibilities in perspective and encourage clients to take time to think about their decision. When a risk is found, counselors frequently reassure parents that they were not responsible for the result. An informed choice without pressure or coercion is made when all relevant information has been given and understood.
(1-2%) but provide more definitive results. Increased risk result is commonly presented in positively and negatively ways. While families seek direction and suggestions from the counselors, they are reassured that no right or wrong answer exists. When discussing possible choices, counselor discourse predominates and is characterized by examples of what some people might do. Discussion enables people to place the information and circumstances into the context of their own lives. Clients are given a decision-making framework they can use to situate themselves. The outcomes of tests may reveal normal results but chromosomal anomaly and fetal death are possibilities. Counselors focus on the importance of individual choice and do not encourage deliberation during their informative sessions. Testing is offered because some diagnosed conditions cannot be changed in any way and there is no therapy or treatment available to make it better. Therefore, parents must decide how they should proceed in their pregnancy after learning that their fetus has a potential condition.
or Chorionic villus sampling
).
(trisomy 21), but is not aware of more uncommon conditions such as Edwards’ syndrome (trisomy 18) and Patau syndrome
(trisomy 13). Clients are usually aware of diagnostic testing from friends, TV/press, or because of family history.
No simple correlation has been found between the change in technology to the changes in values and beliefs towards genetic testing. Some think that genetic testing is a great advance while others think it will cause trouble. Despite lack of adequate knowledge, Kitsiou-Tzeli et al. found that most Greek women are satisfied with the information they receive and are willing to undergo testing if they are pregnant again.
Family planning
Family planning is the planning of when to have children, and the use of birth control and other techniques to implement such plans. Other techniques commonly used include sexuality education, prevention and management of sexually transmitted infections, pre-conception counseling and...
. This complex process can be separated into diagnostic (the actual estimation of risk) and supportive aspects.
Genetic counselors
The National Society of Genetic CounselorsNational Society of Genetic Counselors
The National Society of Genetic Counselors , founded and incorporated in 1979, is the largest association of genetic counselors in the world...
(NSGC) officially defines genetic counseling as the process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease. This process integrates:
- Interpretation of family and medical histories to assess the chance of disease occurrence or recurrence.
- Education about inheritance, testing, management, prevention, resources and research.
- Counseling to promote informed choices and adaptation to the risk or condition.
A genetic counselor is an expert with a Master of Science
Master of Science
A Master of Science is a postgraduate academic master's degree awarded by universities in many countries. The degree is typically studied for in the sciences including the social sciences.-Brazil, Argentina and Uruguay:...
degree in genetic counseling. In the United States they are certified by the American Board of Genetic Counseling.http://www.abgc.net Most enter the field from a variety of disciplines, including biology
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
, genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
, nursing
Nursing
Nursing is a healthcare profession focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life from conception to death....
, psychology
Psychology
Psychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...
, public health
Public health
Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals" . It is concerned with threats to health based on population health...
and social work
Social work
Social Work is a professional and academic discipline that seeks to improve the quality of life and wellbeing of an individual, group, or community by intervening through research, policy, community organizing, direct practice, and teaching on behalf of those afflicted with poverty or any real or...
. Genetic counselors should be expert educators, skilled in translating the complex language of genomic medicine into terms that are easy to understand.
Genetic counselors work as members of a health care team and act as a patient advocate as well as a genetic resource to physicians. Genetic counselors provide information and support to families who have members with birth defects or genetic disorder
Genetic disorder
A genetic disorder is an illness caused by abnormalities in genes or chromosomes, especially a condition that is present from before birth. Most genetic disorders are quite rare and affect one person in every several thousands or millions....
s, and to families who may be at risk for a variety of inherited conditions. They identify families at risk, investigate the problems present in the family, interpret information about the disorder, analyze inheritance patterns and risks of recurrence, and review available genetic testing
Genetic testing
Genetic testing is among the newest and most sophisticated of techniques used to test for genetic disorders which involves direct examination of the DNA molecule itself. Other genetic tests include biochemical tests for such gene products as enzymes and other proteins and for microscopic...
options with the family.
Genetic counselors are present at high risk or specialty prenatal clinics that offer prenatal diagnosis
Prenatal diagnosis
Prenatal diagnosis or prenatal screening is testing for diseases or conditions in a fetus or embryo before it is born. The aim is to detect birth defects such as neural tube defects, Down syndrome, chromosome abnormalities, genetic diseases and other conditions, such as spina bifida, cleft palate,...
, pediatric care centers, and adult genetic centers. Genetic counseling can occur before conception (i.e. when one or two of the parents are carriers of a certain trait) through to adulthood (for adult onset genetic conditions, such as Huntington's disease
Huntington's disease
Huntington's disease, chorea, or disorder , is a neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and dementia. It typically becomes noticeable in middle age. HD is the most common genetic cause of abnormal involuntary writhing movements called chorea...
or hereditary cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
syndromes).
Patients
Any person may seek out genetic counseling for a condition they may have inherited from their biological parents.A woman, if pregnant, may be referred for genetic counseling if a risk is discovered through prenatal testing (screening or diagnosis). Some clients are notified of having a higher individual risk for chromosomal abnormalities or birth defects. Testing enables women and couples to make a decision as to whether or not to continue with their pregnancy, and helps provide information that can be used to prepare for the birth of a child with medical issues.
A person may also undergo genetic counseling after the birth of a child with a genetic condition. In these instances, the genetic counselor explains the condition to the patient along with recurrence risks in future children. In all cases of a positive family history for a condition, the genetic counselor can evaluate risks, recurrence and explain the condition itself.
Counseling session structure
The goals of genetic counseling are to increase understanding of genetic diseases, discuss disease management options, and explain the risks and benefits of testing. Counseling sessions focus on giving vital, unbiased information and non-directive assistance in the patient's decision making process. Seymour Kessler, in 1979, first categorized sessions in five phases: an intake phase, an initial contact phase, the encounter phase, the summary phase, and a follow-up phase. The intake and follow-up phases occur outside of the actual counseling session. The initial contact phase is when the counselor and families meet and build rapport. The encounter phase includes dialogue between the counselor and the client about the nature of screening and diagnostic tests. The summary phase provides all the options and decisions available for the next step. If counselees wish to go ahead with testing, an appointment is organized and the genetic counselor acts as the person to communicate the results.Reasons and results
Families or individuals may choose to attend counseling or undergo prenatal testing for a number of reasons.- Family history of a chromosome abnormality
- Molecular test for single gene disorder
- Increased maternal age (>35 years)
- Abnormal serum screeningTriple testThe triple test, also called triple screen, the Kettering test or the Bart's test, is an investigation performed during pregnancy in the second trimester to classify a patient as either high-risk or low-risk for chromosomal abnormalities .The term "multiple-marker screening test" is sometimes used...
results or ultrasoundUltrasoundUltrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...
findings - Increased nuchal translucency
- Strong family history of cancer
- Predictive testing for adult-onset conditions
Detectable conditions
Most disorders cannot occur unless both the mother and father pass on their genes, such as Cystic FibrosisCystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...
. Some diseases can be inherited from one parent, such as Huntington’s disease. Other genetic disorders are the cause of an error or mutation occurring during the cell division process (trisomy
Trisomy
A trisomy is a type of polysomy in which there are three copies, instead of the normal two, of a particular chromosome. A trisomy is a type of aneuploidy .-Description and causes:...
). Testing can reveal conditions that are easily treatable as long as they are detected (Phenylketonuria or PKU
Phenylketonuria
Phenylketonuria is an autosomal recessive metabolic genetic disorder characterized by a mutation in the gene for the hepatic enzyme phenylalanine hydroxylase , rendering it nonfunctional. This enzyme is necessary to metabolize the amino acid phenylalanine to the amino acid tyrosine...
). Results from genetic testing may also reveal:
- Down syndromeDown syndromeDown syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...
- Sickle-cell anemia
- Tay-Sachs diseaseTay-Sachs diseaseTay–Sachs disease is an autosomal recessive genetic disorder...
- Spina bifidaSpina bifidaSpina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through...
- Muscular dystrophyMuscular dystrophyMuscular dystrophy is a group of muscle diseases that weaken the musculoskeletal system and hamper locomotion. Muscular dystrophies are characterized by progressive skeletal muscle weakness, defects in muscle proteins, and the death of muscle cells and tissue.In the 1860s, descriptions of boys who...
- Mental retardationMental retardationMental retardation is a generalized disorder appearing before adulthood, characterized by significantly impaired cognitive functioning and deficits in two or more adaptive behaviors...
Genetic counselors as support
Genetic Alliance states that counselors provide supportive counseling to families, serve as patient advocates and refer individuals and families to community or state support services. They serve as educators and resource people for other health care professionals and for the general public. Many engage in research activities related to the field of medical genetics and genetic counseling. The field of genetic counseling is rapidly expanding and many counselors are taking on "non-traditional roles" which includes working for genetic companies and laboratories. When communicating increased risk, counselors anticipate the likely distress and prepare patients for the results. Counselors help clients cope with the emotional, psychological, medical, social, and economic consequences of the test results.Each individual considers their family needs, social setting, cultural background, and religious beliefs when interpreting their risk. Clients must evaluate their reasoning to continue with testing at all. Counselors are present to put all the possibilities in perspective and encourage clients to take time to think about their decision. When a risk is found, counselors frequently reassure parents that they were not responsible for the result. An informed choice without pressure or coercion is made when all relevant information has been given and understood.
Prenatal genetic counseling
If an initial noninvasive screening test reveals a risk to the fetus, clients are encouraged to attend genetic counseling to learn about their options. Further prenatal investigation is beneficial and provides helpful details regarding the status of the fetus, contributing to the decision-making process. Decisions made by clients are affected by factors including timing, accuracy of information provided by tests, and risk and benefits of the tests. Counselors present a summary of all the options available. Clients may accept the risk and have no future testing, proceed to diagnostic testing, or take further screening tests to refine the risk. Invasive diagnostic tests possess a small risk of miscarriageMiscarriage
Miscarriage or spontaneous abortion is the spontaneous end of a pregnancy at a stage where the embryo or fetus is incapable of surviving independently, generally defined in humans at prior to 20 weeks of gestation...
(1-2%) but provide more definitive results. Increased risk result is commonly presented in positively and negatively ways. While families seek direction and suggestions from the counselors, they are reassured that no right or wrong answer exists. When discussing possible choices, counselor discourse predominates and is characterized by examples of what some people might do. Discussion enables people to place the information and circumstances into the context of their own lives. Clients are given a decision-making framework they can use to situate themselves. The outcomes of tests may reveal normal results but chromosomal anomaly and fetal death are possibilities. Counselors focus on the importance of individual choice and do not encourage deliberation during their informative sessions. Testing is offered because some diagnosed conditions cannot be changed in any way and there is no therapy or treatment available to make it better. Therefore, parents must decide how they should proceed in their pregnancy after learning that their fetus has a potential condition.
Referral
After attending counseling, women have the option of accepting the risk revealed and having no further treatment during their pregnancy. They may choose to undergo noninvasive screening (Triple screen) or invasive diagnostic testing (AmniocentesisAmniocentesis
Amniocentesis is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, in which a small amount of amniotic fluid, which contains fetal tissues, is sampled from the amnion or amniotic sac surrounding a developing fetus, and the fetal DNA is examined for...
or Chorionic villus sampling
Chorionic villus sampling
Chorionic villus sampling , sometimes misspelled "chorionic villous sampling", is a form of prenatal diagnosis to determine chromosomal or genetic disorders in the fetus. It entails sampling of the chorionic villus and testing it...
).
Attitudes toward counseling
The general public lack adequate knowledge of screening and diagnostic tests and their consequences. The plethora of information available can be overwhelming and counselors spend a large proportion of time clarifying details. Prenatal screening was first introduced nearly four decades ago, yet gaps still exist in public knowledge about the screening program. The general public is familiar with Down syndromeDown syndrome
Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...
(trisomy 21), but is not aware of more uncommon conditions such as Edwards’ syndrome (trisomy 18) and Patau syndrome
Patau syndrome
Patau syndrome, also known as trisomy 13 and trisomy D, is a chromosomal abnormality, a syndrome in which a patient has an additional chromosome 13 due to a nondisjunction of chromosomes during meiosis. Some are caused by Robertsonian translocations...
(trisomy 13). Clients are usually aware of diagnostic testing from friends, TV/press, or because of family history.
No simple correlation has been found between the change in technology to the changes in values and beliefs towards genetic testing. Some think that genetic testing is a great advance while others think it will cause trouble. Despite lack of adequate knowledge, Kitsiou-Tzeli et al. found that most Greek women are satisfied with the information they receive and are willing to undergo testing if they are pregnant again.
See also
- Full Genome SequencingFull genome sequencingFull genome sequencing , also known as whole genome sequencing , complete genome sequencing, or entire genome sequencing, is a laboratory process that determines the complete DNA sequence of an organism's genome at a single time...
- National Society of Genetic CounselorsNational Society of Genetic CounselorsThe National Society of Genetic Counselors , founded and incorporated in 1979, is the largest association of genetic counselors in the world...
- ReprogeneticsReprogeneticsReprogenetics is a term referring to the merging of reproductive and genetic technologies expected to happen in the near future as techniques like germinal choice technology become more available and more powerful. The term was coined by Lee M...
- Genomic counselingGenomic counselingGenomic counseling is the process by which a person gets informed about his or her genome. In contrast to genetic counseling, which focuses on Mendelian diseases and typically involves person-to-person communication with a medical genetics expert, genomic counseling is not limited to currently...