Interpreting Pedigrees
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Activity 8: Interpreting Pedigrees
Get
Started
Read the introduction.

A pedigree shows generations and
relationships among biological parents
and offspring. It also tracks which of those
individuals have a specific trait.
Activity 8: Interpreting Pedigrees
Challenge

What information can
geneticists obtain by analyzing
a pedigree?
Activity 8: Interpreting Pedigrees
Analyzing Pedigrees
Activity 8: Interpreting Pedigrees
Pedigree A: Huntington’s Disease
Activity 8: Interpreting Pedigrees
Pedigree B: PKU
Activity 8: Interpreting Pedigrees
Pedigree C: Hemophilia
Activity 8: Interpreting Pedigrees
Analysis 2

Examine the pedigree below for grain plants with a
trait for a high amount of protein. What can you
determine about the trait based on the pedigree?
Activity 8: Interpreting Pedigrees
Follow Up
Analysis 3

How do farmers and agricultural
geneticists use the information provided
by a pedigree to breed desirable traits in
an agricultural crop?
Activity 8: Interpreting Pedigrees
Analysis 4

On the next slide is a pedigree for cattle that have
been genetically modified to produce a human
protein that helps prevent blood clots in humans.
Using the information in the pedigree, answer the
following questions:
a. What type of inheritance mechanism—dominant,
recessive, or sex-lined recessive—is shown in the
pedigree? Support your answer with evidence.
b. From the information in the pedigree from generation 3,
can you determine if the gene is still present in the cow
population? Explain why or why not?
Activity 8: Interpreting Pedigrees
Analysis 4, continued
Activity 8: Interpreting Pedigrees
Revisit the
Challenge

What information can
geneticists obtain by analyzing
a pedigree?
Activity 8: Interpreting Pedigrees
Key
Vocabulary







allele
carrier
Dominant
pedigree
recessive
sex-linked
sex-linked recessive
Activity 8: Interpreting Pedigrees