Inheritance of Genetic Disorders: Jigsaw Activity
TEACHER INFORMATION
Role of Expert
Each student in the class is assigned a particular disorder (Klinefelter’s, Cystic Fibrosis, Tay Sachs, Huntington’s Disease, Down’s Syndrome, Achondroplasia). For homework at least two nights prior to the day of the activity, the student is to use the Internet and/or any textbooks to research the disorder (stamp for homework points). They should print out/write down information that pertains to the following (encourage them to highlight the information on a printout):
- Symptoms—How would you recognize this condition in a family member? (What physical & psychological characteristics are associated with this genetic condition?)
- Cause—What is the "cause" of this disorder? (sex-linked, Autosomal, recessive, dominant, mutation, chromosomal abnormality, etc.)
- Treatment—Is there any treatment for this condition? Is there a way to prevent this condition?
- Screening—Is there a way to screen individuals for this condition
- Percentages—What percentage of the population is thought to have this condition? Is it more common in certain populations (ethnicity, region of the world, only in boys or girls)?
- Society—How has society interpreted these variant genetic conditions? (Are individuals with this condition accepted by society, shunned, institutionalized, teased, etc.)
- Any diagrams—Are there any relevant pictures that help illustrate the cause of the disease? (Ex: Is there a picture of nondisjunction? Is there a diagram of the lungs of a person with Cystic Fibrosis?)
You may do either of the following for credit on this assignment:
Option #1: Write the answers on a sheet of binder paper. Note your source.
Option #2: Print out information from the Internet. HIGHLIGHT the parts that answer the above questions. Note your source. (You may find it easier to copy and paste the relevant information into a Word document).
Vocabulary that should be used to explain the cause of the disorder:
Autosomal
Meiosis
Mutation
Nondisjunction (sex chromosomes or autosomes)
Sex-linked (or X-linked)
On the day of the jigsaw, allow each of the students who researched the same topic to gather together to compare information. Any discrepancies need to be cleared up as much as possible, and the expert group should agree on all of the information that they are going to disperse in their home groups.
Remind the experts that they need to be able to explain their subject in their own words, and that how well they understand their subject will be important to others in the group.
After the expert groups have met, pass out the genetic disease table that each student will fill out in their home groups. Each expert group can fill out their section of the table in their expert group so that the information similar (and accurate).
Role of home groups
Next, instruct each home group to meet.
Each expert will take turns teaching the others about their subject. Remind the students to share information verbally—no exchange of tables. Make sure that each student has a firm grasp of each of the disorders and that his or her table is completely filled out.
No matter what option you choose, be thorough! Others are depending on you to get the correct information!
Inheritance of Genetic Disorders: Follow Up
Directions: Independently, please answer the following questions as thoroughly as possible. Use your genetic disease table to help you.
- Describe the problem during meiosis that would result in a person having Klinefelter’s Syndrome. (Use a diagram (labeled) if you wish.)
2.Explain why a person with Achondroplasia has a 50% chance of having a child with the disorder (even if he or she marries a person who does not have the disorder).
- How does the inheritance of Tay Sachs differ from the inheritance of Huntington’s Disease?
- How does the inheritance of Klinefelter’s disease differ from the inheritance of Down’s Syndrome?
- What is the chance of a person who is a carrier for Tay Sachs passing on the allele to his child?
- Why can a person be considered a carrier for a disorder such as Cystic Fibrosis, but not for a disorder such as Achondroplasia (hint: they are both autosomal, but how are they inherited?)
- X-linked disorders are carried on the X chromosome. Explain how a man can be a carrier for a disorder like Cystic Fibrosis, but not a carrier for an X-linked disorder, such as Hemophilia.
GENETIC DISORDER / Symptoms / Cause / Treatment / Testing / Probability/
Percentages / Society / Misc. /Diagrams
Klinefelter’s Syndrome
Cystic Fibrosis
Tay Sachs
Symptoms / Cause / Treatment / Testing / Probability
/Percentages / Society / Diagrams/Misc.
Huntington’s Disease
Down’s Syndrome
Achondroplasia