This investigative case module was prepared as part of a BioQUEST faculty development workshop entitled Selected Cases at Beloit College in June 1999. The cases, resources, and implementation strategies were developed by participants for use with their own students. We invite you to adopt and adapt the following materials.

The BioQUEST Curriculum Consortium is committed to the reform of undergraduate biology instruction through an emphasis on engaging students in realistic scientific practices. This approach is sometimes characterized as an inquiry driven approach and is captured in BioQUEST's three P's (problem-posing, problem-solving, and peer-persuasion). As part of this workshop groups of faculty were encouraged to initiate innovative curricular projects. We are sharing these works in progress in the hope that they will stimulate further exploration, collaboration and development. Please see the following links for additional information:

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Investigative Cases
The Case: Decisions

“I’m so afraid, though, honey…” Elise blurted as she pushed the burning log back onto the fire. The reflection of the fire on the lake’s surface shone through the darkness.

“Every night as I tuck in Julia, my heart breaks as I think of her suffering … I don’t want that heartache with another child, and they say if we conceive again, there’s a good chance the baby will have CF as well. I know she has hope as she begins participating in her clinical trials for the gene therapy, but it’s all too much for me to handle.”

“But there’s so many new techniques on the horizon, Elise,” said Joe. "Henry was just telling me the other night about PGD and also the possibility of new prenatal gene therapies. I know they’re experimental, but I love you and want more children! Julia is so special to me”…

“She’s special to me, too, Joe!” interjected Elise,
“but … I’m not sure that I’m comfortable with those new techniques. I guess maybe we could adopt… I’ll tell you what. I’ll do some research about those techniques when we get back home.
I promise."

Case Author:
Donna Maus Fort Scott Community College

Case Analysis

Option: Include a know / need to know chart like the one below:

What do you know?
What do you need to know?

Learning Goals


  • students will know the cause, symptoms and prognosis of cystic fibrosis.
  • students will be able to predict the chances of two carriers of CF having a child w/ CF.
  • students will have a working knowledge of PGD, gene therapy, and prenatal gene therapy.
  • students will use this knowledge to analyze the ethical ramifications of using these techniques.



Investigations and Activities

This is from the website, where the student will do their interactive Punnett Square activity…..

Working out Punnett Square Examples 

Using Punnett squares you can work out the probabilities that children of the parents in each example will have particular phenotypes and genotypes.

Monohybrid crosses

Dihybrid crosses



Students will usually obtain additional references or resources to help answer or explore their questions.

"Prenatal gene therapy: can the technical hurdles be overcome?" Molecular Medicine Today, April 1999

Students will usually obtain additional references or resources
to help answer or explore their questions.

Special Data Items

Students will complete the tutorial.

Students will submit a paper that summarizes their knowledge of CF, PGD, gene therapy and states their opinion as to the decision they would make in the couple’s situation.

Students will compose and perform a skit about their respective positions.

1. decisions1a.jpg
2. decisions3.gif
3. decisions4.jpg


Student Products

  • Using weblinks and other resources, students will do the research necessary to fulfill the objectives.
  • Students will practice monohybrid crosses using the computer tutorial.
  • Students will form groups of 4 to discuss the pros and cons of using each option presented, then perform a skit or other oral presentation demonstrating their individual conclusions regarding the bioethics of each option.
  • Students will take a short quiz over objectives.

Assessment and Evaluation Plan

Students will be assessed according to the following parameters:

Quiz - 15%

Paper - 50%

Performance of skit - 25%

Peer evaluation - 10%



Sample Lesson Plan

Day 1

  • Students read case and do scenario analysis within pre-formed groups:

    What is this case about?
    What do we already know?
    What do we want to know?
    How will we proceed to find the answers to our questions?

  • The instructor will check this list and provide direction to each group prior to the next activity.

  • They then will use the resources made available to begin answering their questions.

  • Time required: 50 minutes class time, to be completed as homework.

Day 2

  • tutorial will be used to allow individual work doing monohybrid crosses.
  • Students will then get back into their groups to discuss and outline their knowledge of PGD, gene therapy, cystic fibrosis and prenatal gene therapy. The scribe will summarize the findings of the group.
  • Students will generate 5 quiz questions that assess understanding of PGD, cystic fibrosis and gene therapy. This quiz will be administered to another group, along with a punnett square activity used to predict CF inheritance.
  • Required class time: 50 minutes

Day 3

  • Students will meet in groups to identify the stakeholders of the case, and discuss the bioethics of the various options from the viewpoints of the different stakeholders.
  • They will then take time to compose their skit or another form of oral presentation.
  • The required paper will be a homework assignment.
  • Required class time: 50 minutes

Day 4

  • Skits/oral presentations from each group.
  • Class time required: 50 minutes

Course name:
Introductory Biology
Likely sequence in syllabus:
During Genetics
Time during term:
4 days
Classroom, Field
Students in course:
Majors and Non-majors
Collaborative elements:
Group work, presentation
Additional notes:




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