What Genes are You Wearing? Teacher Lesson Plans and Case Notes

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1 What Genes are You Wearing? Teacher Lesson Plans and Case Notes Rationale: Medical technology is advancing rapidly. Some of the therapies and techniques already available seemed like science fantasy only a few years ago. Conversely, the public sometimes has the impression that technology is further along than it is and that doctors can produce miraculous cures for a vast array of conditions. This state of misconception is understandable. Exposure to new technologies often comes via popular movies, television shows, novels, and ---unfortunately---sensationalized news accounts. These sources can provide confusing and erroneous impressions to a public that is increasingly asked to sort fact from fiction and make important healthcare decisions for themselves and their families. An important aim of all science classes is to help students develop into scientifically literate adults, so that they will be prepared to evaluate new information and make informed choices in their adult lives. One much-talked-about emerging technology is gene therapy, which will hopefully be used to effect cures for disorders, diseases, and syndromes that have genetic causes. The genetic problems could be hereditary or mutagenic, but in either case delivery of normal genes to target cells could theoretically produce a cure. Whenever there is talk about changes to the genome of an organism, whether it is a person or a variety of corn, fear of the unknown, cultural trappings, and fantasy add confusion to an already difficult topic. This lesson is intended for use after a study of DNA replication, transcription, and translation to help students become familiar with the workings of gene therapy and give them an opportunity to practice making informed decisions regarding their personal health. Given a genetic disorder, they will decide: Should I participate in a clinical trial of a new gene therapy that might be able to cure me? Standards: National Science Education Standards: 12ASI1.1 Identify questions and concepts that guide scientific investigations. They should demonstrate appropriate procedures, a knowledge base, and conceptual understanding of scientific investigations. 12ASI1.2 Design and conduct scientific investigations. Regardless of the scientific investigation performed, students must use evidence, apply logic, and construct an argument for their proposed explanations. 12ASI1.4 Formulate and revise scientific explanations and models using logic and evidence. Student inquiries should culminate in formulating an explanation or model. Models should be physical, conceptual, and mathematical. In the process of answering the questions, the students should engage in discussions and arguments that result in the revision of their explanations. These discussions should be based on scientific knowledge, the use of logic, and evidence from their investigation. 12CLS1.3 Cells store and use information to guide their functions. The genetic information stored in DNA is used to direct the synthesis of the thousands of proteins that each cell requires.

2 12CLS2.1 In all organisms, the instructions for specifying the characteristics of the organism are carried in DNA, a large polymer formed from subunits of four kinds (A, G, C, and T). The chemical and structural properties of DNA explain how the genetic information that underlies heredity is both encoded in genes (as a string of molecular "letters") and replicated (by a templating mechanism). Each DNA molecule in a cell forms a single chromosome. 12CLS2.2 Most of the cells in a human contain two copies of each of 22 different chromosomes. In addition, there is a pair of chromosomes, which determine sex: a female contains two X chromosomes and a male contains one X and one Y chromosome. Transmission of genetic information to offspring occurs through egg and sperm cells that contain only one representative from each chromosome pair. An egg and a sperm unite to form a new individual. The fact that the human body is formed from cells that contain two copies of each chromosome and therefore two copies of each gene explains many features of human heredity, such as how variations that are hidden in one generation can be expressed in the next. 12CLS2.3 Changes in DNA (mutations) occur spontaneously at low rates. Some of these changes make no difference to the organism, whereas others can change cells and organisms. Only mutations in germ cells can create the variation that changes an organism s offspring. Georgia Performance Standards SB2. Students will analyze how biological traits are passed on to successive generations. b. Explain the role of DNA in storing and transmitting cellular information. c. Describe the relationships between changes in DNA and potential appearance of new traits including Alterations during replication. Insertions Deletions Substitutions Mutagenic factors that can alter DNA. High energy radiation (x-rays and ultraviolet) Chemical f. Examine the use of DNA technology in forensics, medicine, and agriculture. Hook: Go to the following link and play My So-Called Lungs. This National Public Radio twenty-two-minute audio clip is highlights from the oral diary of Laura Rothenberg. At the time Rothenberg was a nineteen year-old cystic fibrosis patient who recorded her experiences for the radio program, All Things Considered. The clip first aired on August 5 th, Laura died in March of This recording will introduce the idea of a young person suffering from a genetic disorder. Students will recognize that Laura is much like them and will develop empathy for people who suffer from life threatening illnesses. Students will need time to discuss their feelings and impressions. Allow for discussion time after listening, and guide them, if necessary, to talk about genetic disorders.

3 Student Task 1: The Challenge Break up your class into groups of four or five students, assigning one of the following diseases to each group: HIV Cystic fibrosis Hemophilia Muscular dystrophy Rheumatoid arthritis Coronary heart disease Alzheimer s disease Ulcer Bone fracture Cancer Sickle cell anemia Huntington s disease Tay-sach's disease Give each student a What Genes are you Wearing? packet that is tailored to his or her group s disease. Each student should read the challenge and answer the questions on their own before they get together as a group to compare and share. If time allows have groups compare and share in a whole class room discussion You are a 16 year old who suffers from. Recently your condition has been worsening and you have been spending an enormous amount of time in and out of the doctor s office and hospital. You are tired of being sick and just want the opportunity to be a teenager. Your primary care physician has recently come to you and your family and suggested that you undergo gene therapy. You have no idea what gene therapy is or how it works. Your doctor keeps stating that you are lucky because there is a new study starting within the month at your local hospital to test a gene therapy protocol for your disease. The gene therapy is very experimental and still in the very early stages of development, and the outcome of the treatment is uncertain. You have a week to decide if you want to become a part of this study. Thoughts to Ponder Answer each question below, using the information above, your prior knowledge, and your initial thoughts about this situation: What information do you know? What questions do you have? What questions can be answered with further research?

4 Compare, and share your questions with your group members. Student Task 2: Meet the Experts Show the two short video clips linked from Problem 1 Home Page, After viewing, have groups answer the questions listed below the video synopses. Have a whole-class discussion, comparing and sharing answers. These synopses are provided for teacher reference. It is best to allow students to view the videos without reading the synopses or giving too much introduction. Video One What is gene therapy? Dr. Joe Le Doux, a researcher, provides the students with 'scaffolding' or 'points of reference' to help them think about gene therapies. He encourages them to classify their particular disease and treatment and to think about why these classifications are important - for example, why is it important to consider whether a gene therapy involves permanent or transient modification of the cells? Video Two When is gene therapy appropriate? Dr. Peter Thule, clinical doctor and researcher, focuses on the concept of risk vs. benefit analysis. Once they've classified their particular situation, patients should determine what things can go wrong with their gene therapy (GT), how serious those things are, and how probable it is for these adverse events to occur. They should then compare their answers to what things can go right, how good those things are (for example, in comparison to current treatments, if the GT is successful, will the patient live longer or have a higher quality of life?), and how likely it is that these good things will happen. Finally, patients should weigh the pros and cons and make a decision based on that analysis. 1) Watch these two videos. 2) Answer the following questions: Who were in the videos? Why are they considered experts? What information did you learn from these experts? Were any of your old questions answered? Do you have any new questions?

5 Student Task 3: Research/Revise This next activity can be done during class time in a computer lab or may be assigned for homework. Have students complete the Research and Revise Activity: Web Quest. The web quest handout can be found at Student Handouts on the Problem 1 Home Page, Tell students to write down their group s questions in the space provided on the webquest. Have students divide up the questions so that each student is answering about four questions, and more than one student is answering each question. EXAMPLE: Mary will answer 1, 4, 6, and 7 John will answer 1, 2, 3, and 7 Chris will answer 2, 4, 5, and 6 Mark will answer 3, 4, 5, and 7 Each question is being answered by at least two people so that multiple perspectives can be assembled. Once they have answers to their questions, have them come back into groups and discuss their answers. Have students come up with a consensus answer for each question. Using the websites given, answer all of the questions that you have been assigned by your group. When complete, share your answers with your group members and compare answers to like questions. Are your answers the same? Different? Why? Come up with one GROUP answer for each question. Student Task 4: Test your Mettle This activity is first done individually. Have students complete Gene Therapy or Not?, found at Student Handouts on the Problem 1 Home Page, Students are given a list of ten diseases and asked to rank them in order, from what they consider the most negative to what they consider least negative. Students then reconvene with their groups and arrive at a consensus ranking. Each group elects an official to represent them in a class legislature. This legislature should gather to discuss and vote on a final ranking, with the result being that the top ranked diseases will have higher priority for available funding for research into gene therapy treatments. While the legislature is out of the room, lead the rest of the class in a discussion about genetic disorders, the role of government in medical research, and any other issues that arise. Once the legislature returns, they report their ranking. Students should reflect on how this ranking compares with their own personal ranking. This is a good time to talk about the benefits of communicating with your representatives in government and other issues that impact funding for research.

6 Student Task 5: Go Public This activity would be done a couple of days after Test Your Mettle in order to allow students enough time to confer with their guardians. Allow students to talk over their decisions with their group members. Groups must come to a consensus: Will they will join the clinical trial or not? Have groups present their decision to the class with their rationale. 1) Present the information you have learned to your parent or guardian. Together you should make a decision about whether or not you will participate in the clinical trial. Complete the Permission Form with your parent or guardian and bring the signed form to your next doctor s appointment on. 2) You will come back to class, and your group will come to a consensus together. 3) Your group will present its decision to the class. Be prepared to defend your reasoning.