Download Investigating Pedigrees Name: Example Pedigree: Example case

Investigating Pedigrees
Name:
Example Pedigree:
Example case study:
 Annie has a genetic skin condition (ss).
 Neither of her parents (John and Luci) have it.
 Annie’s brother George has it.
 Neither of Annie’s sisters (Maggie and Ona) have it.
Draw a pedigree for this family in the space below and write the possible
genotypes of each family member next to their symbol.
Case Study 1: Joshua and Bella
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Joshua and Bella have a son named Ian.
Ian has been diagnosed with cystic fibrosis, a recessive genetic disorder.
(cc)
Joshua and Bella are both healthy.
Bella’s mom and dad are both healthy.
Joshua’s mom and dad are both healthy.
Joshua’s sister, Sara, has cystic fibrosis.
Bella’s brother, Edward, also has cystic fibrosis.
In the space below, draw a pedigree using the symbols shown on the example
page. Fill in each person’s genotype next to their symbol on the pedigree. If
there genotype has more than one possibility, put them both down. Then,
answer the questions below.
Pedigree for Joshua and Bella’s families:
1.
List the family members who are carriers for cystic fibrosis:
2.
List the family members who have cystic fibrosis:
3.
Read about cystic fibrosis on page 126 in your book. List three facts
about this genetic disorder:
Case Study 2: Li and Mai
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The father, Li, has sickle cell anemia. The mother, Mai, does not.
Li and Mai’s first child, a girl named Gemma, has the same condition as Li.
Mai’s sister has sickle cell, but Mai’s parents do not.
Li has one brother who does not have the condition, and one sister who
does.
Li’s mother has sickle cell. His father does not.
In the space below, draw a pedigree using the symbols shown on the example
page. Fill in each person’s genotype next to their symbol on the pedigree. If
there genotype has more than one possibility, put them both down. Then,
answer the questions below.
Pedigree for Li and Mai’s families:
4.
What is the probability that Mai and Li’s next child will have sickle cell
anemia?
5.
Why might pedigree charts be useful? (see page 129 for help)
6.
Read about sickle-cell disease on page 126-127. List 3 facts about this
disease:
Case Study 3: The challenge
Choose a genetic disorder listed in the book. Create your own pedigree case
study in the space below. Then, complete the pedigree with the family members
genotypes next to their symbol. Finally, write down and answer 2 questions
about your pedigree or your disease.
Case Study:
Questions: