Genetic counseling (Salem Health: Cancer)
Why performed: Genetic counseling is intended to provide information to people about their risk for the occurrence or recurrence of a specific type or types of cancer. Genetic counselors are not able to determine the risk that a specific individual will develop any type of cancer but rather can determine the risk of specific cancers for which the person is believed to be at increased risk.
People are usually considered good candidates for genetic counseling if they have an unusually high number of close relatives with a certain type of cancer, have relatives who have had multiple types of cancer, have had very unusual cancers, or have developed cancer at an unusually young age.
The risk assessment done during genetic counseling can give people important information that can help them make the best possible medical and lifestyle choices. For example, if a woman finds out that she has an extremely elevated risk of developing breast cancer, she may consider the option of preventive breast tissue removal. People found to have an increased likelihood of developing cancer can work with their physician and other medical professionals to help develop more intensive screening regimens to ensure that the cancer will be caught as early as possible if it does develop.
Steps of the procedure: The genetic counselor discusses and explains the possible risks and benefits of testing and also what kind of...
(The entire section is 1130 words.)
For Further Information (Salem Health: Cancer)
Pupecki, Sandra R., ed. Genetic Screening: New Research. New York: Nova Science, 2006.
Schneider, Katherine A.. Counseling About Cancer: Strategies for Genetic Counseling. 2d ed. New York: Wiley-Liss, 2002.
Skirton, Heather, Christine Patch, and Janet Williams. Applied Genetics in Healthcare: A Handbook for Specialist Practitioners. New York: Taylor & Francis Group, 2005.
Young, Ian D. Introduction to Risk Calculation in Genetic Counseling. 3d ed. New York: Oxford University Press, 2007.
(The entire section is 66 words.)
The Establishment of Genetic Counseling (Genetics & Inherited Conditions)
Historically, people have long understood that some physical characteristics are hereditary and that particular defects are often common among relatives. This concept was widely accepted by expectant parents and influenced the thinking of many scientists who experimented with heredity in plants and animals. Many efforts were made to understand, predict, and control the outcome of reproduction in humans and other organisms. Gregor Mendel’s experiments with garden peas in the mid-1800’s led to the understanding of the relationship between traits in parents and their offspring. During the early twentieth century, Walter Sutton proposed that newly discovered hereditary factors were physically located on complex structures within the cells of living organisms. This led to the chromosome theory of inheritance, which explains mechanically how genetic information is transmitted from parents to offspring in a regular, orderly manner. In 1953, James Watson and Francis Crick (along with Maurice Wilkins and Rosalind Franklin) discovered the double-helix structure of DNA, the molecule that carries the genetic information in the cells of most living organisms. Three years later, human cells were found to contain forty-six chromosomes each.
These discoveries, along with other developments in genetics, periodically generated efforts (often misguided) to control the existence of “inferior” genes, a concept...
(The entire section is 542 words.)
The Training of the Genetic Counselor (Genetics & Inherited Conditions)
Most genetic counseling students have undergraduate degrees in genetics, nursing, psychology, biology, social work, or public health. Training programs for genetic counselors are typically two-year master’s-level programs and include field training in medical genetics and counseling in addition to a variety of courses focusing on genetics, psychosocial theory, and counseling techniques. During the two-year program, students obtain an in-depth background in human genetics and counseling through coursework and field training at genetic centers. Coursework incorporates information on specific aspects of diseases, including the prognoses, consequences, treatments, risks of occurrence, and prevention as they relate to individuals or families. Field training at genetic centers enables students to develop research, analytical, and communication skills necessary to meet the needs of individuals at risk for a genetic disease.
Many genetic counselors work with M.D. or Ph.D. geneticists and may also be a part of a health care team that may include pediatricians, cardiologists, psychologists, endocrinologists, cytologists, nurses, and social workers. Other genetic counselors are in private practice or are engaged in research activities related to the field of medical genetics and genetic counseling. Genetic counseling most commonly takes place in medical centers, where specialists work together in clinical...
(The entire section is 214 words.)
The Role of the Genetic Counselor (Genetics & Inherited Conditions)
Prior to the 1960’s, most genetic counselors were individuals with genetic training who consulted with patients or physicians about specific risks of occurrence of genetic diseases. It was not until 1959, when French geneticist Jérôme Lejeune discovered that children with Down syndrome have an extra chromosome 21, that human genetics was finally brought to the attention of ordinary physicians. Rapid growth in knowledge of inheritance patterns, improvements in the ability to detect chromosomal abnormalities, and the advent of screening programs for certain diseases in high-risk populations all contributed to the increased interest in genetic counseling. Development of the technique of amniocentesis, which detects both chromosomal and biochemical defects in fetal cells, led to the increased specialization of genetic counseling. By the 1970’s, training of genetic counselors focused on addressing patients’ psychosocial as well as medical needs. Genetic counseling thus became a voluntary social service intended exclusively for the benefit of the particular family involved.
Genetic counselors provide information and support to families who have members with genetic disorders, individuals who themselves are affected with a genetic condition, and families who may be at risk for a variety of inherited genetic conditions, including Huntington’s disease (Huntington’s chorea), cystic fibrosis, and Tay-Sachs...
(The entire section is 516 words.)
Diagnosis of Genetic Abnormalities (Genetics & Inherited Conditions)
In the latter half of the twentieth century, discoveries in genetics and developments in reproductive technology contributed to the advancements in prenatal diagnosis and genetic counseling. Prenatal diagnostic procedures eventually became an established part of obstetrical practice with the development of amniocentesis in the 1960’s, followed by ultrasound, chorionic villus sampling (CVS), and fetal blood sampling. Amniocentesis, CVS, and fetal blood sampling are ways to obtain fetal cells for analysis and detection of various types of diseases. Amniocentesis, a cytogenetic analysis of the cells within the fluid surrounding the fetus, is performed between the fifteenth and twentieth weeks of gestation and detects possible chromosomal abnormalities such as Down syndrome and trisomy 18. The information obtained from CVS is similar to that obtained from amniocentesis, except the testing can be performed earlier in the pregnancy (during the tenth to twelfth weeks of gestation). Fetal blood sampling can be performed safely only after eighteen weeks of pregnancy. An ultrasound, offered to all pregnant women, uses high-frequency sound waves to create a visual image of the fetus and detects anatomical defects such as spina bifida, cleft lip, and certain heart malformations. Pedigree analysis may also be used for diagnostic purposes and to determine the risk of passing a genetic abnormality on to future generations. A...
(The entire section is 499 words.)
Ethical Aspects of Genetic Counseling (Genetics & Inherited Conditions)
With advancements in human genetics and reproductive technology, fundamental moral and ethical questions may arise during difficult decision-making processes involving genetic abnormalities for which families may be unprepared. Diagnosis of a particular genetic disease may allow individuals or families to make future plans and financial arrangements. However, improvements in the capability to diagnose numerous hereditary diseases often exceed the ability to treat such diseases. The awareness that an unborn child is genetically predisposed toward a disease with no known cure may lead to traumatic anxiety and depression. The psychological aspects of genetic counseling and genetic centers must therefore continue to be explored in genetic centers throughout the world.
Questions about who should have access to the data containing patients’ genetic makeup must also be considered as the ability to screen for genetic diseases increases. Violating patients’ privacy could have devastating consequences, such as genetic discrimination in job hiring and availability of health coverage. Employers and insurance companies have already denied individuals such opportunities based on information found through genetic testing. Disclosure of genetic information not only contributes to acts of discrimination but also may result in physical and psychological harm to individuals.
With data derived from the Human...
(The entire section is 316 words.)
Further Reading (Genetics & Inherited Conditions)
Leroy, Bonnie, Dianne M. Bartels, and Arthur L. Caplan, eds. Prescribing Our Future: Ethical Challenges in Genetic Counseling. New York: Aldine de Gruyter, 1993. Offers ethical insights into the implications of genetic counseling, including the issue of neutrality, the potential impact of the Human Genome Project, workplace ideology of counselors, and the role of public policy.
Resta, Robert G., ed. Psyche and Helix: Psychological Aspects of Genetic Counseling. New York: Wiley-Liss, 2000. Articles reprinted from numerous sources cover topics pertaining to the medical, social, psychological, and emotional effects of genetic diseases, including the management of guilt and shame, patient care, and a detailed analysis of a genetic counseling session.
Rothman, Barbara Katz. The Tentative Pregnancy: How Amniocentesis Changes the Experience of Motherhood. Rev. ed. New York: Norton, 1993. Provides a discussion of decisions faced by patients who seek genetic counseling.
Schneider, Katherine A. Counseling About Cancer: Strategies for Genetic Counseling. 2d ed. New York: Wiley-Liss, 2002. A thorough resource to help genetic counselors and other health care providers effectively assist patients and families in managing hereditary cancer. Gives clinical features of thirty cancer syndromes, tables listing major cancer syndromes by cancer type, and many case studies.
(The entire section is 344 words.)
Web Sites of Interest (Genetics & Inherited Conditions)
American Board of Genetic Counseling. http://www.abgc.net/english/view.asp?x=1. The Web site for a professional organization that educates, administers examinations, and certifies genetic counselors.
The Centre for Genetics Education. http://www.genetics.com.au/pdf/factsheets/fs03.pdf. A two-page handbook, in pdf format, providing an introduction to genetic counseling for consumers.
Human Genome Project Information, Genetic Counseling. http://www.ornl.gov/sci/techresources/Human_Genome/medicine/Genecounseling.shtml. Site links to genetic counseling information and related resources.
Making Sense of Your Genes: A Guide to Genetic Counseling. http://www.nsgc.org/client_files/GuidetoGeneticCounseling.pdf. An online consumer handbook, in pdf format, prepared by the National Society of Genetic Counselors.
Medline Plus. http://www.nlm.nih.gov/medlineplus/Geneticcounseling.html. Contains numerous links to information about genetic counseling.
National Human Genome Research Institute.. http://www.genome.gov/19016939. Answers frequently asked questions about genetic counseling.
National Society of Genetic Counselors. http://www.nsgc.org. Offers a search engine for locating genetic counselors in the United States and a newsroom with press releases and fact sheets about...
(The entire section is 183 words.)
Science and Profession (Magill’s Medical Guide, Sixth Edition)
Genetic counseling is a process of communicating to a couple the medical problems associated with the occurrence of an inherited disorder or birth defect in a family. Included in this process is a discussion of the prognosis and treatment of the problem. Specific reproductive options include abortion of an ongoing pregnancy, birth control or sterilization to prevent additional pregnancies, artificial insemination, the use of surrogate mothers, embryo transplantation, and adoption.
In all cases, the role of the counselor is to provide unbiased information and options to the couple seeking advice. The counselor must not only discuss the medical implications of a condition but also help to alleviate the emotional impact of positive diagnoses and, in particular, to assuage the guilt or denial that a diagnosis may elicit in parents.
The two major categories of medical problems covered by counselors are birth defects and genetic diseases. The first group includes Down syndrome and spina bifida, while the latter includes hemophilia, sickle cell disease, and Tay-Sachs disease. Although the distinction between these two categories can sometimes blur, the key difference involves the clear pattern of inheritance shown by the genetic diseases.
Humans have between thirty thousand and thirty-five thousand genes. Genes are segments of deoxyribonucleic acid (DNA) that are arranged in linear fashion along the forty-six...
(The entire section is 1359 words.)
Diagnostic and Treatment Techniques (Magill’s Medical Guide, Sixth Edition)
Genetic counseling usually begins when a couple or an individual seeks the advice of a family physician or obstetrician regarding the medical risks associated with having a child. Motivating this request may be a previous birth of a child with a defect, a general uneasiness on the part of a couple worried about environmental exposure to potentially harmful agents, a family history of genetic disease, or advanced maternal age (which can be a factor in certain chromosomal abnormalities). Often, the family is referred to a genetic counseling clinic where most of the actual diagnosis and counseling will occur.
Arriving at a proper diagnosis for any obvious condition, as well as giving advice about potential risks, involves obtaining as much family history as possible with respect to the trait, as well as diagnostic information from the couple. If pregnant already, the woman may undergo a prenatal diagnostic procedure that could include ultrasound, blood tests, amniocentesis, and chorionic villus sampling.
Ultrasound is a technique that uses sound waves to visualize the exterior of the developing fetus. This widely used procedure is almost routine in many large urban hospitals. Ultrasound can be used to detect the presence of twins as well as of some profound birth defects such as hydrocephalus (water on the brain) or spina bifida. The latter defect, which involves the failure of the neural tube to close...
(The entire section is 1214 words.)
Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
The need for centers specializing in genetic counseling arose when it became clear that certain diseases and birth defects had a hereditary component. Many families request the services of counselors from these centers, and the centers are also involved in both voluntary and mandatory screening programs. In the United States, about 4 percent of all newborns suffer from a defect that is recognized either at birth or shortly thereafter. This group includes 0.5 percent who have a chromosomal abnormality that results in an obvious medical problem, 0.5 to 1 percent who have classical genetic diseases, and 2 percent who suffer from a birth defect that may have a heritable component. Estimates vary, but more than one-third of all children in pediatric hospitals are there because of some association with a genetic disease.
Physicians have always served as counselors to families, but the rapid advances made in genetics and molecular science during the second half of the twentieth century have clearly surpassed the abilities of most physicians to keep current with treatments and diagnoses. The first formal clinic for genetic counseling was established at the University of Michigan in the 1940’s. Most clinics specializing in this field were based at large medical centers; first in major metropolitan areas, and later in smaller population centers.
Genetic counseling clinics usually employ a range of specialists,...
(The entire section is 516 words.)
For Further Information: (Magill’s Medical Guide, Sixth Edition)
Davis, Dena S. Genetic Dilemmas: Reproductive Technology, Parental Choices, and Children’s Futures. 2d ed. New York: Routledge, 2010. Explores real-life medical cases as a means to discuss ethical dilemmas raised by the availability of new reproductive technologies.
Filkins, Karen, and Joseph F. Russo, eds. Human Prenatal Diagnosis. 2d rev. ed. New York: Marcel Dekker, 1990. An advanced sourcebook that describes the procedures of prenatal diagnosis in great detail. Contains information on such issues as risk, reliability, and cost.
Harper, Peter S. Practical Genetic Counselling. 6th ed. New York: Oxford University Press, 2004. A good overview of all aspects of genetic counseling, including a discussion of the types of diagnoses, treatments, risks, and emotional strains associated with counseling. Also gives a history of counseling as a discipline.
Jorde, Lynn B., et al. Medical Genetics. 3d ed. St. Louis, Mo.: Mosby/Elsevier, 2006. An introductory text that covers basic molecular genetics, chromosomal and single gene disorders, immunogenetics, cancer genetics, multifactorial disorders, and fetal therapy.
King, Richard A., Jerome I. Rotter, and Arno G. Motulsky, eds. The Genetic Basis of Common Diseases. 2d ed. New York: Oxford University Press, 2002. Covers advances in the understanding of molecular processes involved in genetic susceptibility and...
(The entire section is 380 words.)
Genetic counseling (Encyclopedia of Genetic Disorders)
Genetic counseling is a communication process by which personal genetic risk information is translated into practical information for families. Genetic counselors are health care professionals with specialized training and experience in the areas of medical genetics and counseling. Genetic counselors are able to assist families by:
- Helping families understand information about birth defects or genetic disorders. This includes explaining patterns of inheritance, recurrence risks, natural history of diseases, and genetic testing options.
- Providing nondirective supportive counseling regarding emotional issues related to a diagnosis or testing options.
- Helping individuals or families make decisions that they are comfortable with based on their personal ethical and religious standards.
- Connecting families with appropriate resources, such as support groups or specific types of medical clinics, locally and nationally.
Types of genetic counseling
Genetic counselors work with people concerned about the risk of an inherited disease. These patients represent several different patient populations. Prenatal genetic counseling is...
(The entire section is 2167 words.)
Genetic Counseling (Encyclopedia of Medicine)
Genetic counseling aims to facilitate the exchange of information regarding a person's genetic legacy. It attempts to:
- accurately diagnose a disorder
- assess the risk of recurrence in the concerned family members and their relatives
- provide alternatives for decision-making
- provide support groups that will help family members cope with the recurrence of a disorder
Genetic counselors work with people concerned about the risk of an inherited disease. The counselor does not prevent the incidence of a disease in a family, but can help family members assess the risk for certain hereditary diseases and offer guidance. Many couples seek genetic counseling because there is a family history of known genetic disorders, infertility, miscarriage, still births, or early infant mortality. Other reasons for participating in genetic counseling may be the influences of a job or lifestyle that exposes a potential parent to health risks such as radiation, chemicals, or drugs. Any family history of mental retardation can be of concern as is a strong family history of heart disease at an early age. Recent statistics show a 3% chance of delivering a baby with birth defects. An additional 2% chance of having a baby...
(The entire section is 1780 words.)
Genetic Counseling (Encyclopedia of Nursing & Allied Health)
Genetic counseling is a communication process by which personal genetic risk information is translated into practical information for families. Genetic counselors are health care professionals with specialized training and experience in the areas of medical genetics and counseling. Genetic counselors are able to assist individuals and families by:
- Helping people to understand information about birth defects or genetic disorders. This includes explaining patterns of inheritance, recurrence risks, natural history of diseases, and genetic testing options.
- Providing nondirective supportive counseling regarding emotional issues related to a diagnosis or testing options.
- Helping individuals and families make decisions with which they are comfortable, based on their personal ethical and religious standards.
- Connecting individuals and families with appropriate resources, such as support groups or specific types of medical clinics, locally and nationally.
There are several purposes or aspects to be addressed within the scope of genetic counseling. These include obtaining a pedigree; tracing ethnicity; exploring issues of consanguinity; and documenting exposures to toxins, diseases, or environmental agents during pregnancy.
In all types of genetic counseling, an important aspect of the counseling process is information gathering about family and medical history. Information gathering is performed by drawing a chart called a pedigree. A pedigree is made of symbols and lines that represent a family history. To accurately assess the risk of inherited diseases, information about three generations of the family, including health status and cause of death, is usually needed. If a family history is complicated, information from more distant relatives may be helpful, and medical records may be requested for any family members who have had a genetic disorder. Thorough examination of a family history may enable a counselor to calculate the probability of occurrence of genetic disorders in the future.
In obtaining a family history, a genetic counselor asks about a person's ethnicity or ancestral origin. There are some ethnic groups that have a higher chance of being carriers of some genetic diseases or abnormalities. For instance, the chance that an African American is a carrier of a gene for sickle cell disease is one in 10. People of Jewish or central European ancestry are likely to be carriers of several conditions, including Tay-Sachs disease, Canavan's disease and cystic fibrosis. People of Mediterranean ancestry are likely to be carriers of a type of anemia called thalassemia. Genetic counselors discuss inheritance patterns of these diseases, carrier risks, and genetic screening or testing options.
Another question a genetic counselor asks in obtaining a family history is whether the couple are related to one another by blood. The practice of marrying or having children with relatives is infrequent in the United States, but is more common in some countries. When two people are related by blood, there is an increased chance for their children to be affected with conditions that are inherited in a recessive pattern. In recessive inheritance, each parent of a child affected with a disease carries a single gene for a disease. The child gets two copies, one from each parent, and is affected. People who have a common ancestor are more likely than unrelated people to be carriers of genes for the same recessively inherited disorders. Depending on family history and ethnic background, blood tests can be offered to couples to get more information about the chance of these conditions occurring.
Exposures during pregnancy
During prenatal genetic counseling, the counselor will ask about pregnancy history. If a woman has taken medications or has had exposure to a potentially harmful substance from the environment such as a chemical, toxin, or radiation, the genetic counselor can discuss the possibility of adverse effects. Ultrasound is often a useful tool to look for some effects of exposure.
There are no physical precautions that are needed before genetic counseling. However, persons who will receive the results of genetic tests should be prepared mentally and emotionally for the possibility of unpleasant information. This includes discussing if they want to know the results of genetic testing and what choices they may have to make based on the information supplied.
Types of genetic counseling
Genetic counselors work with people concerned about the risk of an inherited disease or condition. These people represent several different populations. Prenatal genetic counseling is provided to couples that have an increased risk of birth defects or inherited conditions, and are expecting a child or planning a pregnancy. Pediatric genetic counseling is provided to families with children suspected of having a genetic disorder or with children previously diagnosed with a genetic disorder. Adult genetic counseling is provided to adults with clinical features of an inherited disease or a family history of an inherited disease. Cancer genetic counseling is provided to those with a strong family history of certain types of cancer. Ethics are an important component of genetic counseling.
Prenatal genetic counseling
There are several different reasons a person or couple may seek prenatal genetic counseling. If a woman is age 35 or older and pregnant, there is an increased chance that her fetus may have a change in the number of chromosomes present. Changes in chromosome number may lead to mental retardation and birth defects. Down syndrome is the most common change in chromosome number that occurs proportionally more often in the fetuses of older women. Couples may seek prenatal genetic counseling because of abnormal results of screening tests performed during pregnancy. A blood test called the alpha fetal protein (AFP) test is offered to all pregnant women. This blood test screens for Down syndrome, open spine defects (spina bifida), and another type of mental retardation caused by a change in chromosome number called trisomy 18. When this test is abnormal, further tests are offered to get more information about the chance of these conditions actually occurring in the fetus. Another reason that people seek prenatal genetic counseling is a family history of birth defects or inherited diseases. In some cases, blood tests of the parents may be available to indicate if their children would be at risk of being affected. Genetic counselors assess risk in each case, help persons to understand their risks, and explore how they feel about or will cope with these risks.
Prenatal tests that are offered during genetic counseling include level II ultrasounds, maternal serum AFP screening, chorionic villus sampling (CVS), and amniocentesis. Level II ultrasound is a detailed ultra-sound surveying fetal anatomy for birth defects. Ultrasound is limited to detection of structural changes in anatomy and cannot detect changes in chromosome number. The maternal serum AFP screening is used to indicate if a pregnant woman has a higher or lower chance of having a child with certain birth defects. This test can only provide information concerning the probability of a birth defect. The screening cannot diagnose an actual birth defect. CVS is a way of learning how many chromosomes are present in a fetus. A small piece of placental tissue is obtained for these studies during the tenth to twelfth weeks of pregnancy. Amniocentesis is also a way of learning how many chromosomes are present in a fetus. Amniotic fluid is obtained for these studies, usually between 15 and 20 weeks of pregnancy. There is a small risk of miscarriage associated with both of these tests. Genetic counseling regarding these procedures involves the careful explanation of benefits and limitations of each testing option. A genetic counselor also tries to explore how persons feel about prenatal testing and the impact of such testing on the pregnancy. Genetic counselors are supportive of any decision a person makes about whether or not to have prenatal tests performed.
Pediatric genetic counseling
Families or pediatricians seek genetic counseling when a child has features of an inherited condition. Any child who is born with more than one birth defect; mental retardation; or dysmorphic features has an increased chance of having a genetic syndrome. A common type of mental retardation in males for which genetic testing is available is Fragile X syndrome. Genetic testing is also available for many other childhood illnesses such as hemophilia and muscular dystrophy. Genetic counselors work with medical geneticists to determine if a genetic syndrome is present. This process includes a careful examination of family history, medical history of the child, review of pertinent medical records in the family, a physical examination of the child, and sometimes blood work or other diagnostic tests. If a diagnosis is made, then a medical geneticist and genetic counselor review what is known about the inheritance of the condition, the natural history of the condition, treatment options, further examinations that may be needed for health problems common in the diagnosed syndrome, and resources for helping the family. The genetic counselor also helps the family adjust to the diagnosis by providing emotional support and counseling. Many families are devastated by receiving a diagnosis, learning of the likely outcome for the child and by the loss of the hoped for healthy child. There would also be a discussion about recurrence risks in the family and who else in the family may be at risk.
Adult genetic counseling
Adults may seek genetic counseling when a person in the family decides to be tested for the presence of a known genetic condition; when an adult begins exhibiting symptoms of an inherited condition; or when there is a new diagnosis of someone with an adult-onset disorder in the family. In addition, the birth of a child with obvious features of a genetic disease leads to diagnosis of a parent who is more mildly affected. Genetic counseling for adults may lead to the consideration of presymptomatic genetic testing. Testing a person to determine the likelihood for a condition existing before any symptoms occur is an area of controversy. Huntington's disease is an example of a genetic disease for which presymptomatic testing is available. This is a neurological disease resulting in dementia. Onset of the condition is between 30 and 50 years of age. Huntington's disease is inherited in an autosomal dominant pattern. If a person has a parent with the disease, the risk of being affected is 50%. Would presymptomatic testing relieve or create anxiety ? Would a person benefit from removal of doubt about being affected? Would knowing about the condition help a person with life planning? Genetic counselors help people sort through their feelings about such testing and whether or not the results would be helpful to them.
Cancer genetic counseling
A family history of early onset breast, ovarian, or colon cancer in multiple generations of a family is a common reason a person would seek a genetic counselor who works with people who have cancer. While most cancer is not inherited, there are some families in which a dominant gene is present and causing the disease. A genetic counselor is able to discuss the chances that the cancer in the family is related to a dominantly inherited gene. The counselor can also discuss the option of testing for the breast and ovarian cancer genes, BRCA1 and BRCA2. In some cases the persons seeking testing have already had cancer but others have not. Therefore, presymptomatic testing is also an issue in cancer genetics. Emotional support is important for these people, as they have often lost close relatives from cancer and are fearful of their own risks. For families in which a dominant form of cancer is detected through genetic testing, a plan can be made for increased surveillance of disease symptoms.
Ethical issues in genetic counseling
Prenatal diagnosis of anomalies or chromosomal abnormalities may lead to a decision about whether or not a couple wishes to continue a pregnancy. Some couples choose to continue a pregnancy. Prenatal diagnosis gives them additional time to emotionally prepare for the birth of the child and to gather resources. Others choose not to continue a pregnancy in which problems have been diagnosed. These couples have unique emotional needs. Often the child is a very much desired addition to the family and parents are devastated that the child is not healthy. Presymptomatic testing for adult-onset disorders and cancer raises difficult issues regarding the need to know and the reality of dealing with abnormal results before symptoms occur. The National Society of Genetic Counselors has created a Code of Ethics to guide genetic counselors in caring for people. The Code of Ethics consists of four ethical principles:
- Beneficience is the promotion of personal well-being in others. The genetic counselor is an advocate for the person being counseled.
- Non-maleficience is the concept of doing no harm to a person.
- Autonomy is recognizing the value of an individual, the person's abilities and point of view. Important aspects of autonomy are truthfulness with persons, respecting confidentiality, and practicing informed consent.
- Justice is providing equal care for all, freedom of choice, and providing a high quality of care.
The main ethical principle of genetic counseling is the attempt to provide nondirective counseling. This principle again points to an individual-centered approach to care by focusing on the thoughts and feelings of each person. Five percent of the Human Genome Project budget is designated for research involving the best way to deal with ethical issues that arise as new genetic tests become available. Genetic counselors can help people navigate through the unfamiliar territory of genetic testing.
Persons should be apprised of possible outcomes and given the opportunity to discuss their feelings prior to undergoing genetic tests. There is a burden associated with knowing the probability of a future outcome. Difficult decisions may be required as a result of learning genetic information through testing. The process of adequately preparing an individual for genetic counseling is called informed consent. Ethical genetic counselors always obtain informed consent prior to undertaking any genetic tests.
Persons must be provided access to competent counselors and therapists. Such professionals can assist in processing the feelings and reactions that may emerge as a result of receiving the findings of genetic tests.
The complications that arise from the process of genetic counseling are most commonly mental and emotional. Individuals and couples who have received genetic counseling often experience mental changes such as depression and anguish when they receive unfavorable results about tests. Complications include the need to make difficult decisions regarding themselves, their families, or their unborn children. This is also referred to as a burden of knowing, meaning that likely but unwanted outcomes may become known before they occur. Depending on the condition, personal preferences and situation, persons may elect to continue with a pregnancy that is likely to result in a child with one or more abnormalities, terminate a pregnancy, select a different partner, or decide not to have children. These are all difficult situations that may require the assistance and intervention of a trained mental health counselor or therapist.
The results given to a person during genetic counseling are highly individualized and depend on the nature of tests being performed and the issues of importance to the person being counseled.
The results of the process of genetic counseling vary. Genetic counseling offers information to people, thereby allowing them to make informed choices. Some of the options may not be easy or pleasant to contemplate. However, they are based on hard data rather than on wishes, hopes, or some other non-scientific basis. Genetic counselors have an ethical duty to obtain informed consent from individuals prior to beginning genetic counseling, provide unbiased information and the ability to interact in a non-judgmental or coercive manner.
Health care team roles
Genetic counselors are specially trained members of a health care team who have a master's degree in genetic counseling. They receive referrals from obstetricians, pediatricians, family physicians, and other doctors. They interpret the results of tests from laboratory personnel, medical geneticists, and pathologists. They refer people to therapists and counselors for assistance in resolving issues that arise from the process of genetic counseling.
Canavan disease serious genetic disease more common among the Eastern European Jewish population that causes mental retardation and early death. Canavan disease is caused by the lack of an enzyme called aspartoacylase.
Cystic fibrosis respiratory disease characterized by chronic lung disease, pancreatic insufficiency, and an average age of survival of 29 years. Cystic fibrosis is caused by mutations in a gene on chromosome seven that encode a transmembrane receptor.
Dysmorphic feature subtle change in appearance such as low set ears or a flattened nasal bridge that suggests a genetic syndrome may be present.
Fragile X syndromehe most common inherited cause of mental retardation in males. People with Fragile X syndrome often have large ears, a long face, hyperextensible finger joints, hyperactivity or autism. Fragile X syndrome is caused by an expansion in a gene on the X chromosome. Some females are also affected. Human Genome Projectn international collaborative project among scientists to map the genetic sequence of all the chromosomes. This project is funded by the National Institute of Health in the United States.
Informed consentrovision of complete information to a competent individual regarding a treatment or test. Part of informed consent is to ensure a person's understanding of the advantages and disadvantages of a procedure and to obtain voluntary authorization to perform the procedure. Sickle-cell anemia chronic, inherited blood disorder characterized by crescent-shaped red blood cells. It occurs primarily in people of African descent, and produces symptoms including episodic pain in the joints, fever, leg ulcers, and jaundice.
Tay-Sachs disease genetic disease affecting young children of eastern European Jewish descent. This disease is caused by the lack of an enzyme called hexosaminidase A. This deficiency results in mental retardation, convulsions, blindness and, finally, death.
Thalassemian inherited group of anemias occurring primarily among people of Mediterranean descent. It is caused by abnormal formation of part of the hemoglobin molecule.
Beaudet, Arthur L. "Genetics and disease." In Harrison's Principles of Internal Medicine, 14th ed., edited by Anthony S. Fauci, et al. New York: McGraw-Hill, 1998, 365-395.
Eanet, Karen, and Julia B. Rauch. Genetics and Genetic Services: A Child Welfare Worker's Guide. Washington, DC: Child Welfare League of America, 2000.
Hollingsworth, Alan B. The Truth About Breast Cancer Risk Assessment. Aurora, CO: National Writers Press, 2000.
Kessler, Seymour, and Robert G. Resta. Psyche and Helix: Psychological Aspects of Genetic Counseling. New York: Wiley, 2000.
Meager, Anthony. Gene Therapy Technologies, Applications and Regulations: From Laboratory to Clinic. New York: Wiley, 1999.
Needleman, Robert D. "Fetal growth and development." In Nelson Textbook of Pediatrics, 16th ed. edited by Richard E. Behrman et al., Philadelphia: Saunders, 2000, 27-30.
Seashore, Margretta R. "Genetic counseling." In Cecil Textbook of Medicine, 21st ed. edited by Goldman, Lee and Bennett, J. Claude. Philadelphia: W.B. Saunders, 2000, 439-442.
Weil, Jon. Psychosocial Genetic Counseling. New York: Oxford University Press, 2000.
Brooks, S.S. "Genetic counseling in the neuronal ceroid lipofuscinoses." Advances in Genetics 45 (2001): 159-167.
Brunger, J.W., Matthews AL, Smith RH, Robin NH. "Genetic testing and genetic counseling for deafness: The future is here." Laryngoscope 111, no. 4 Pt 1 (2001): 715-718.
Ciske, DJ, Haavisto A, Laxova A, Rock LZ, Farrell PM. "Genetic counseling and neonatal screening for cystic fibrosis: An assessment of the communication process." Pediatrics 107, no. 4 (2001):699-705.
Edwards, R.T. "Steering a course around the genetic iceberg." Journal of Public Health Medicine 23, no. 1 (2001): 3-4.
Ralston, SJ, Wertz D, Chelmow D, Craigo SD, Bianchi DW. "Pregnancy outcomes after prenatal diagnosis of aneuploidy." Obstetrics and Gynecology 97, no. 5 Pt 1 (2001): 729-733.
Welkenhuysen, M, Evers-Kiebooms G, d'Ydewalle G. "The language of uncertainty in genetic risk communication: Framing and verbal versus numerical information." Patient and Educational Counseling 43, no. 2 (2001): 179-187.
American Board of Genetic Counseling, 9650 Rockville Pike, Bethesda, MD 20814-3998. (301) 571-1825. Fax: (301) 571-1895. <<a href="http://www.faseb.org/genetics/abgc/abgcmenu.htm">http://www.faseb.org/genetics/abgc/abgcmenu.htm>.
American Infertility Association, 666 Fifth Avenue, Suite 278, New York, NY 10103. (718) 621-5083. <<a href="http://www.americaninfertility.org">http://www.americaninfertility.org>. email@example.com.
American Public Health Association, 800 I Street, NW, Washington, DC 20001-3710. (202) 777-2742. Fax: (202) 777-2534. <<a href="http://www.apha.org">http://www.apha.org>. firstname.lastname@example.org.
American Society for Reproductive Medicine, 1209 Montgomery Highway, Birmingham, AL 35216-2809.(205) 978-5000. <<a href="http://www.asrm.com">http://www.asrm.com>.
American College of Physicians. <<a href="http://www.acponline.org/journals/news/feb95/gencoun.htm">http://www.acponline.org/journals/news/feb95/gencoun.htm>.
March of Dimes. <<a href="http://www.modimes.org/HealthLibrary2/faq/Genetic_Counseling.htm">http://www.modimes.org/HealthLibrary2/faq/Genetic_Counselin... >.
National Human Genome Research Institute. <<a href="http://www.nhgri.nih.gov/DIR/VIP/Glossary/pub_glossary.cgi/pub_glossary.cgi?key=genetic%20counseling&view_value_pair=on">http://www.nhgri.nih.gov/DIR/VIP/Glossary/pub_glossary.cgi/... >.
National Library of Medicine. <<a href="http://www.nlm.nih.gov/medlineplus/genetictestingcounseling.html">http://www.nlm.nih.gov/medlineplus/genetictestingcounseling... >.
National Society of Genetic Counselors. <<a href="http://www.nsgc.org">http://www.nsgc.org>.
Rush University School of Medicine. <<a href="http://www.rush.edu/worldbook/articles/007000a/007000027.html">http://www.rush.edu/worldbook/articles/007000a/007000027.ht... >.
University of Kansas Medical Center. <<a href="http://www.kumc.edu/gec/prof/gc.html">http://www.kumc.edu/gec/prof/gc.html>.
World Medical Association. <<a href="http://www.wma.net/e/policy/17-s_e.html">http://www.wma.net/e/policy/17-s_e.html>.
L. Fleming Fallon, Jr., MD, DrPH