The Human Genome Project has provided us the ability to peek into our genes- allowing us to see a glimpse of not only our own future, but of the future of our children and grandchildren. This peek allows us to question, and quite possibly change the course of disease before we are faced with the physical manifestation of the disorder. With this great wealth of information comes the potential for many ethical debates. Are there things that we do not want to know about our health? Who owns the rights to our genetic information? This activity examines some of the ethical issues that surround genetic testing, genetics research and personal choices regarding the information gained through modern technology.
Objectives:
1. Discuss the topic of ethics in genetics in an informed and mature manner.
2. Understand the inheritance pattern and basic genetics of Huntington's Disease.
3. Address the personal, emotional and social implications of disease in the genomic era.
The following scenario provides a basis for a series of ethical questions related to genetic disease and to the potential issues inherent in the information contained in our genome. Prior to the scenario, students should investigate and be familiar with the basic pattern of inheritance, genetics, symptoms and clinical course of Huntington's Disease. The initial scenario allows the student to research the biology of codon repeats and investigate how a genetic disease can change in strength from generation to generation. You may wish to have students complete the Huntington's Disease Webquest available on the Woodrow Wilson site before beginning the ethical discussion. If necessary, students should research the definitions of the underlined terms in the scenario and related questions.
The following case can be used in the classroom in a variety of ways.
The teacher may distribute the case study to individuals, to small groups or pose the questions to the entire class. The questions may be extended into a debate, a larger project involving a survey of classmates or family on these ethical issues, or into a written essay to be completed by the student. The scenario and questions can be used in their entirety or in parts.
Scenario
Sue is an 19-year-old college student. Desperate for a little extra spending money, Sue responds to an ad in the local paper and volunteers to donate a blood sample to a company setting up a genetic database. On her follow-up visit, Sue is shocked to learn that she carries the gene for Huntington's Disease. As she researches the disease, she realizes that one of her parents must also express the Huntington's gene and that they will most likely become symptomatic in the next ten years. She is baffled however, when she notes that all of her grandparents, both maternal and paternal, have entered their 60s without symptoms. As she begins to research the genetics of the disease, she realizes that one of her grandparents may have had the gene, but never expressed the phenotypic disease. How is that possible? If you were a genetic counselor, what could you tell her about codon expansion diseases and genetic anticipation of the disease from generation to generation?
Ethical Questions
Sue's head is spinning from all the issues she must now face.
1.Should she tell her parents what she has learned or is this something her parents need to find out for themselves? Seeing that there is no treatment for the disorder and that they are unable to bear more children, is there any reason for them to worry about Huntington's disease before the symptoms begin? Assuming that she is relatively close to her parents, is there really any way she could (or would) keep this information from them? But do her parents have a right "not to know"?
2.Recently Sue and her boyfriend, Steve, have discussed marriage. Does her boyfriend have a right to know of her status before he makes plans to marry and have children? She knows that if she chooses to have children, there is a 50% chance that her child will inherit the disease. As far as she is concerned, she has two options- she can have a tubal ligation to ensure that she can not pass the gene for Huntington's disease to offspring or she can choose to conceive, knowing that pre-zygotic testing may be able to tell her whether or not her child has the disease. However, she is on the fence when it comes to terminating a pregnancy. What are the pros and cons of both options? Are there any other options Sue has not considered?
3.When Sue begins applying for jobs, does she have to enter this information into her medical history? What are potential repercussions if she does/does not offer this information?
4. Upon enrolling in the genetic study with this private company, Sue signed a consent form ensuring that her information would be catalogued by a number and that her medical history would not be linked to her name. Sue has some concerns about ability of the company to keep her information private. What problems can arise if the company releases her information without permission or if someone manages to "steal" this information out of the database? What concerns should Sue have about the possibility that her health insurance company might access her genetic information? Who has the ultimate rights to Sue's genetic history?
5.Sue begins to investigate potential treatments for Huntington's disease and finds that the options are severely limited. She does however find multiple studies investigating the disease in animal models with homologs of the Huntington's disease. What is the value of using mice and drosophila models to investigate the clinical course, genetics and treatment of the disease. Sue has always been morally opposed to animal testing. How could you argue the pros and cons of their use in this case? Do you think her opinions may change now that she has Huntington's disease?
6. As a result of the original study, Sue may be offered the opportunity to participate in clinical trials investigating the effectiveness of experimental treatments for Huntington's disease. These treatments might include gene therapy or pharmacotherapy. What questions should she ask and what concerns should she have before she agrees to participate in these trials?
For more information about codon repeat diseases and the genetics of Huntington's Disease, check out the following links:
http://www.sciencedaily.com/releases/1998/10/981007072150.htm
http://www.stanford.edu/group/hopes/rltdsci/trinuc/f0.html
www.geneclinics.org/profiles/huntington
http://www.ich.ucl.ac.uk/cmgs/hunt98.htm
www.ultranet.com/~jkimball/BiologyPages/M/Mutations.html
http://www.hda.org.uk/research/rs027.html
http://www.cs.rhul.ac.uk/home/jhancock/pdf/Detal96.pdf
Understanding Scientific as Inquiry
Describe how genetic information is inherited and expressed.
Explain gene inheritance and expression at the molecular level.
Students are influenced by societal, cultural, and personal beliefs and ways of viewing the world
Personal goals, peer and social pressures, ethnic and religious beliefs, and understanding of biological consequences can all influence decisions about health practices.