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Chapter 6 Genes: Identifying, Choosing, & Using Them
The eugenics pioneers had dreams of bettering society by making improvements in humans through their genes. They had, of course, no awareness of what genes (the so-called "heritable factors") were, no concept of DNA, no sense of where genes might be located, or how one might alter them.
Today, the eugenicists' dreams are much closer to realities. Scientists working on the Human Genome Project know how to identify genes and associate them with the traits and characteristics they encode, the proteins and other products they produce, and the actions they perform. One day they hope to be able to repair damaged genes and replace defective ones.
Doctors and researchers already can test fetuses for the presence of genes that are associated with approximately 400 conditions. (Adults are sometimes also tested for these genes.) Obstetricians sample the cells-and within them, the genes and biochemicals-of fetuses and then search for genetic and biochemical markers and defects. With 'imaging' devices, doctors look for physical defects in fetuses. These tests spot problems early on, and sometimes the problems can be fixed while the fetus is still in utero (through surgery) or in a timely fashion by interventions at birth.
Spina bifida, Down's syndrome, hemophilia, cystic fibrosis, sickle cell anemia, polydactyly (an extra little finger), and color-blindness are just some of the conditions and diseases that can be identified through prenatal testing. Currently, most of the conditions discovered through prenatal testing are neither treatable nor curable. Some may never be. But others may be amenable to fixing some time in the future. Awareness gained from prenatal testing does permit parents to prepare psychologically and physically-purchase or rent special equipment; arrange for treatments or other forms of help-for the birth of a child who will have some special needs (see cases in Unit 1) or may give them time to consider terminating the pregnancy.
What should be the goals of prenatal testing? Probably all would agree that one valuable goal is to support the births of healthy children. Another is to fix what can be fixed in a timely fashion.
People with certain disabilities worry that prenatal testing is heading down the slippery slope toward eliminating the births of more people like themselves. Many scholars and others agree that this is already happening. They point to the unstated expectation that, when fetuses have certain genetic diseases and physical deformities, the assumption is that the pregnancy will be terminated. People whose sexual orientation is homosexual worry that prenatal testing might one day also be aimed at eliminating the births of people like themselves.
What do these choices imply about our concepts-those of individuals and of the wider society-concerning the types of people who should and will be born into the world?
How strong is the "technological imperative," which holds that, because a technology exists, it must or should be used? Do future parents have a right or a choice to take advantage of all possible prenatal tests? Do they have a moral or a legal right to choose not to use the tests?
Genes are responsible for making people humans. But they function together with experiences and environment to make people humane. How appropriate is it for individuals or societies to make decisions on the basis of genetic tests that will affect the future of individuals or of humanity?
Included References
- American Journal of Public Health 1999 November; 89(11): 1649-1657.
- Hastings Center Report 1999 September-October 29(5): S1-S22.
Additional Resources
- Play and movie: Twilight of the Golds by Jonathan Tolins
- Hastings Center Report 1997 July-August; 27(4): 14-2
- Robert Crouch, "Letting the Deaf Be Deaf: Reconsidering the Use of Cochlear Implants in Prelingually Deaf Children."
- Hastings Center Report 1997 July-August; 27(4): 6-
- Udo Schuklenk, Edward Stein, Jacinta Kerin, William Byne, "The Ethics of Genetic Research on Sexual Orientation."
AimsStudents should understand the following:
- Through the Human Genome Project, scientists are identifying, mapping, and learning to alter genes
- Not all traits and characteristics are caused by genes
- Technology is neither inherently good or bad; the determinative factor is how it is used
- Human variability adds to the richness of human life
- Everyone has genetic flaws; some are just more visible than others
- Desirable traits and characteristic differ for different individuals
- The slippery slope concept
Suggested Questions for Discussion
- What is prenatal testing?
- Should parents be allowed to select the gender of their offspring?
- Philosopher Adrienne Asch, who is blind, points out that definitions of terms such as "health," "normality," and "disability," are not "clear, objective, and universal across time and place." What are some possible definitions of these terms? Why is agreement on the terms not universal? What is a "social construction?"
- Some diseases are genetic; some are not; some people become ill or disabled as adults. What would society lose by not having people like Itzhak Perlman (who has polio) or Stephen Hawking (who has Lou Gehrig's disease) in it? Does consideration of these individuals alter your opinion about the possibility of terminating pregnancies in which the fetus is found to have a disability? Cite other examples of people who, though disabled, are mostly known for their talents and accomplishments.
Topics for Discussion/Written Assessment
- Genetic counselors work with women and their partners to help them learn about their risks of having children with particular genetic diseases. They also describe the options for prenatal testing and help them understand what the results and the consequences might be. The Code of the National Society of Genetic Counselors requires that counseling be non-directive. What is non-directive counseling? Why is it considered important? Can counselors be truly objective? Why?
- What influence do you think the early eugenics programs and the atrocities of the Holocaust had on the choice of the National Society of Genetic Counselors to insist on non-directive counseling? What are the strengths and limitations of this stance?
- Some adults with genetic conditions note that, because genetic testing is supposed to be non-directive-providing information but not advice about what to do-they should be allowed to use the new technologies to select for children who have the same genetic conditions they have, such as deafness or achondroplasia (a form of dwarfism). What are the social, political, ethical, and economic issues that support/oppose their position?
- Some individuals who are disabled or have genetic diseases fear that, through prenatal genetic testing, people like themselves will one day no longer be born. How can or should society respond to these concerns? What efforts are already underway to ensure that this does not happen? How successful are they so far? How successful are they likely to be?
Extension Questions for Additional Research
- What are some positive uses that prenatal testing has already been put to? What diseases or conditions can be corrected or ameliorated through prenatal testing and treatments?
- In addition to prenatal testing, three other types of genetic testing are now possible: (a) testing of newborns, (b) testing of adults who are thinking about having babies, and (c) testing of children and adults for predispositions to late-onset disorders. What is the status of each of these types of testing? For what diseases and conditions are they now available? How common is the testing? What can be done when the test shows that a person has the gene for a disease or condition of interest?
- Some individuals and couples are using new reproductive technologies-in vitro fertilization, egg donation, sperm donation-to produce children. Some place ads in newspapers, requesting that women donate eggs to them. They might specify that they want the donor to be tall, have a high IQ, be attending an Ivy League school, and so on. Recent requests have received tremendous media attention, as have advertisements on the web. The assumption of the requestors is that, once they select a donor of a certain type, the resulting child will be just like the donor. What happens to a child who does not measure up to expectations, who is less athletic, less attractive, and less smart than the parents wished?
- People raise concerns about the uses of data from the Human Genome Project in light of what happened in the name of eugenics during the Holocaust. The argument is that, as the genome is mapped and individual genes are connected to specific conditions and diseases, people could be targeted for sterilization or for other forms of discrimination because they carry certain genes. How valid are these concerns? How are they being addressed in the policies of the Human Genome Project?
- China's one-child policy led to wide-spread use of sex selection for male babies and to abortion of female babies and their release for international adoptions. What is the history of the one-child policy? What are the known consequences in China of the policy? How has the composition of Chinese society changed? What other long-term effects of these practices might be likely to occur?
- India's cultural tradition encourages a preference for male children. What have been the effects of sex selection in India?
- Some genes may have more than one function. Sometimes one function is a helpful one and another is a deleterious one. Learn about the gene for sickle cell anemia. What are the benefits associated with this gene? What problems does it cause? What other genes are in this category?
- What position does the Society of Genetic Counselors take on prenatal testing for sex selection? Check their website at http://www.nsgc.org.
- Should people be allowed to choose the sex of their offspring? Why? Who should regulate such selection?
Topics for Teacher Preparation
- Human Genome Project
- Technological imperative
- Parents' rights
- Rights of the unborn
- Disability issues and perspectives
- Variations in sexual orientations
- Economic and social issues relating to disabilities
Curriculum Materials That Focus on Genetics and the Human Genome Project
- Human Genetic Variation: available from http://science-education.nih.gov/nihhtml/colsupp/nhgri-hu.htm
- High School Human Genome Program: http://hshgp.genome.washington.edu/
- Several curriculum modules produced by Biological Sciences Curriculum Study: http://www.bscs.org/cp_hs.html
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