Jenny is a teenager facing a critical decision. Should she have DNA testing for Huntington’s disease (HD), a genetic disease that took the life of her grandmother? Why does her mother insist that Jenny get tested? Why won’t her father get tested when he’s started to show symptoms of HD? What are the potential consequences of this decision for Jenny and for her family? Jenny’s dilemma is the basis for Family Secrets, a problem-based learning (PBL) curriculum module that focuses on the bioethical implications of genetic testing.

 

Family Secrets uses a progressive disclosure PBL strategy (figure shown to the right). Students work in teams to arrive at solutions to a real-life problem presented in a five-part scenario that focuses on different stages in Jenny’s life. These stages are presented to students as scenarios in scripts that students read aloud. Students work individually and then in teams to identify the facts and questions posed by the scenarios, conduct research, and report their findings. Each part of the scenario discloses additional information that encourages students to research and discuss Jenny’s dilemma from different perspectives.

In Part 1, A Family Disease, and Part 2, The Dilemma, students learn about genetic disorders (specifically, HD) and about issues involving genetic counseling, DNA testing, and informed consent. Students work in teams, and use the PBL strategy to identify facts from the scripts that introduce Jenny and her family. Students then identify questions that arise from the script. Examples of these questions may include:

  • What is HD?
  • How is it inherited?
  • What happens if you inherit the HD gene?
  • How do you test for the HD gene?

Students use internet and print resources provided to research answers to the questions. Students report what they have learned to their team, and each team reports to the class.

 

Between Part 1 and Part 2, teachers a use sticky notes “Topical Barometer” (figure shown to the left) to graphically represent student answers to the question “If you were Jenny, would you have genetic testing?” Each student places a sticky note on the Topical Barometer to represent one of five possible answers to this question.

Part 3, A Difficult Choice, begins with teachers introducing the basic concepts of ethics, and ends with students using an eight-step ethical decision-making process. The introduction to ethics involves understanding the four major ethical principles of autonomy (freedom to choose), justice (playing fair), beneficence (doing good), and nonmalefesance (avoiding harm). Students also learn about basic ethical values such as confidentiality and privacy, honesty, fidelity, and integrity. The whole class first works together to identify the ethical problem and the stakeholders involved. PBL teams then identify possible courses of action, and match these actions with ethical principles and values. Teams weigh the risks, benefits, and consequences of each course of action. Students then work individually to select and support one course of action. Part 3 ends with the class revisiting the “Topical Barometer” activity, modified now to two possible answers to the question of having genetic testing done.

 

Part 4, Testing for the HD Gene, engages students in playing the roles of laboratory technicians. They are provided with simulated DNA samples from Jenny, her brother, and her father, and use agarose gel electrophoresis to test for the presence of the HD gene. Students analyze the results and prepare a laboratory report that could be used by a genetic counselor in discussions with Jenny, her brother, or her father.

Part 5, Making Decisions, takes place after Jenny and her family learn the results of the DNA testing. The family and students discover that, even after the test results are known, there are additional ethical, legal, and social issues (ELSI) that the family must face in the future.

Family Secrets includes a comprehensive teacher’s guide (print and CD-ROM) that contains an overview of each of the five PBL parts, followed by detailed, step-by-step instructions and classroom preparation information, including all student handouts. An extensive selection of resources provides teachers and students with background information on DNA and genetic disorders, HD, genetic testing, and bioethics. These resources include annotated links to websites, print resources, PowerPoint presentations, graphics, and animations for teachers to use as engaging supplements to the PBL sessions.

Family Secrets also includes a Virtual DNA Testing Laboratory on CD-ROM that first illustrates and explains background information on genetic testing, and then provides a virtual laboratory simulation of the Part 4, Testing for the HD Gene electrophoresis activity. The virtual lab can be used as an introduction to the gel electrophoresis activity. For schools that do not have electrophoresis equipment, the virtual lab may be used as a replacement for the wet lab.

 

Family Secrets was developed as a collaboration between the University of Rochester 's Life Sciences Learning Center and the New York State Biology-Chemistry Professional Development Network , using grant funding from the National Human Genome Research Institute (NHGRI) .

Read about Family Secrets in the November, 2006 issue of The Science Teacher

For more information about Family Secrets , please contact: dina_markowitz@urmc.rochester.edu