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What is genetic counseling?

What is genetic counseling?.

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What is genetic counseling?

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  1. What is genetic counseling? When Sheldon C. Reed coined the term genetic counseling in 1949-the year after the founding of the American Society of Human Genetics and the year the first modern American textbook in human genetics was published-he was formalizing various activities that "genetic social workers" had provided to families on an individualized basis from early in this century. The hope was to prevent or minimize the risk of recurrence of a serious disorder presumed to be wholly or partly genetically influenced.

  2. Assignment: • Discuss these questions for each case: • 1. What does this client need to know at this meeting about the disease and prognosis? • 2. What events does this person need to plan for now? • 3. What information does this person need from you, now and in the future? • 4. What would make this counseling session easier?

  3. Cases 1, 2 and 3: From the GenEthics Consortium Case Literature http://www.nhgri.nih.gov/About_NHGRI/Dir/Ethics/case_rev.html

  4. Case 1: Suseptibility testing for common disorders: should apoE testing be used for predicting Alzheimer's? (Revised from an original case recorded in GeneLetter Website) Apolipoprotein E (APOE) tests may indicate that an individual with two copies of one form (allele e4) of the gene has a 5-30 times the average risk of developing Alzheimer disease.

  5. Managers of the Silver Years Retirement Community near Pines Bluff decide to require the test for entrance. They argue that people with Alzheimer disease not only cost the retirement community more in terms of nursing care (a cost that is spread among members through high entrance fees), but also have a demoralizing effect on the general atmosphere, thereby discouraging new entrants. In most states, retirement communities may set their own health standards for entrance. The APOE test, however, does not provide a certainty that someone will develop Alzheimer disease; many people with two APOE variants remain normal. Using the test will screen out many persons who are genetically unfortunate but will never develop the disease, but will improve the community's risk pool. If most retirement communities institute testing, these people will be penalized for having the "wrong" genes. Even those who would actually develop Alzheimer disease may die of other causes before they show the first Alzheimer symptoms. Is it fair to exclude people on the basis of a genetic test, in the absence of symptoms or of certainty about whether, and when, they will develop the disease? On the other hand, is it fair to make everyone in the community pay the high costs of nursing care for a few?

  6. Ann and Carl Bradley of Pines Bluff, both nearing 70 years of age, had been planning to seek entrance into the Silver Years Retirement Community. They had been discussing this for some time with each other and with their friends at the local church. Both agree to take the apo E test. Ann's profile is acceptable (alleles 3/2) but Carl's indicates a poor prognosis (4/4), and they are informed that as a couple they would not be granted admission. Both are devastated, and strongly suspect that their friends will know the reason why they will not be carrying out their much-discussed plans. Carl has become severely depressed, and there are strong tensions developing in the marriage. Is it fair that susceptibility tests such as these may be used with significant negative impacts on individuals and families, including their privacy?

  7. Case 2: Genetic research and group impacts: the search for alcoholism genes in the Native American Community RE: Protocol #56345, "The Genetic Basis of Alcoholism in Native American Populations"

  8. As you know, a team of researchers in our Molecular Biology Program wish to study the genetic bases of alcoholism among selected Native American groups. This research is based on recent reports of a significant correlation between alcoholism and several different forms of brain wave activity that are measurable by electroencephalography (EEG). Caucasian and African Americans with these phenotype traits have an elevated risk of alcoholism. There is also developing evidence of genetic linkage to these neuro-physiological traits. Because the prevalence of alcoholism is high in many tribes, this team of researchers believes it is important to ascertain if this phenotype/phenotype/genotype correlation also exists in American Indians. In accordance with Protocol # 56345, three hundred families will be selected among the the Athabascan tribe for study. We will be focusing on families with a high incidence of alcoholism. Subject volunteers will be compensated for their time and effort (compensation for two days participation will average $300).

  9. Recently, I received the following memorandum from a representative body for the Athabascan community: "The Athabascan community urges the IRB committee to reject the study in question. No tribal council nor representative body has been contacted to discuss the concerns that our members might have with the study. This oversight fails to recognize t he legitimate concerns our community has with how this information will be used both scientifically and in keeping with our religious and cultural values. For example, this study makes no mention of how blood samples will be treated. The Athabascan tribe, as do many other Native Americans, traditionally considers all parts of the body sacred, including materials derived from the body (such as blood products or organs), which may no longer serve any function within the body. Of general concern, we note that both communities as a whole and individuals within these communities may be stigmatized by such research. We cite the history of discrimination and stigmatization that has followed Native Americans, particularly in relation to Alcoholism, as proof of this concern. This study offers no immediate benefits and poses significant risk; it should not be approved."

  10. Case 3: Should Preimplantation Genetic Diagnosis be used to select for traits?

  11. A couple is seeking help at a new privately financed clinical program that offers preimplantation genetic diagnosis (PGD). This technology combines in vitro fertilization with molecular analysis of the DNA from single cell of the developing embryo to permit the selection and transfer to the uterus of embryos free of a genetic disease. Before PGD, the only alternative for individuals or couples wishing to prevent the birth of a child with a serious genetic disorder was chorionic villus sampling at 10-12 weeks of pregnancy or amniocentesis at 16 weeks, followed by abortion if the fetus had the disorder. This couple is at risk of having a second child with Severe Combined Immune Deficiency (SCID). Children born with this condition have seriously impaired immune systems. As recently as twenty years ago, children with SCID died early in life, but the use of bone marrow transplantation to provide the child a supply of healthy blood stem cells has greatly extended survival and, in some cases, has made possible a good quality of life. In general, the earlier the transplantation is done and the closer the HLA tissue match of the marrow donor, the better a recipient child's chances of a good outcome.

  12. The couple tell the medical geneticist that they are seeking his help in identifying and transferring only embryos free of the SCID mutation so that they can begin their pregnancy knowing that it will be healthy. Some weeks later they then offer a further reason for their interest in this technology. They explain that they have a six year old daughter with SCID whose health is on a downward course despite one partially matched bone marrow transplant earlier in her life. They realize that their child's best hope of survival is another bone marrow transplant using tissue from a compatible donor, preferably a sibling. Is it possible, they ask, to test the healthy embryos for HLA compatibility and transfer only those that match their daughter's type?

  13. The geneticist responds that it is technically possible to do this. But to himself, he wonders whether helping this couple in this way is an ethically appropriate use of this new genetic technology. Is it right to conceive a child "to purpose" in this way? Also, since HLA status is a genetic trait and not a disease would responding to this request represent an unwise step into a world of positive or "enhancement genetics," where parents' desires, not medical judgment, dictate the use of genetic knowledge?

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