Name: ____________________
PEDIGREE WORKSHEET
1. Is the following pedigree demonstrating an autosomal dominant or autosomal recessive trait?
Use the letters below to figure out the inheritance.
Dominant?
Recessive?
A = has the trait
a = has the trait
a = does not have the trait
A = does not have the trait
2. Is it possible that this pedigree is for an autosomal dominant trait? 3. _______If a person has a dominant trait:
Show the genotypes for each individual. Use “A” and “a” again.
a) the parents will not have the trait
b) the parents might or they might not have it.
c) at least one of the parents will have the trait.
d) both of the parents will have the trait.
4. The pedigree is autosomal dominant.
Use "A" and "a" as you did for the pedigrees above.
Write the genotype of each individual next to the symbol.
5. _______ If two individuals have a dominant trait:
a) none of their offspring will have the trait.
b) their offspring might or might not have the trait.
c) their offspring will have the trait.
6. One of the following pedigrees is autosomal recessive.
Use the following letters to figure out the possible inheritance by showing the genotypes of all individuals.
A = normal
a = the trait (a genetic disease or abnormality)
7. If a trait is autosomal recessive:
a) If both parents are affected, none of the children will be affected.
b) If both parents are affected, the children might or might not be affected.
c) If both parents are affected, all of the children will be affected.
8. If a trait is autosomal recessive and two unaffected parents produce a child with the trait, the parents must be
a) homozygous dominant
b) heterozygous
c) homozygous recessive
9. Is the following autosomal dominant or autosomal recessive? Provide 2 reasons for your answer.
10. The following pedigree shows the inheritance pattern of hemophilia in descendants of Queen Victoria. Hemophilia is a recessive
x linked disorder.
a) Identify what females are certain to be carriers
b) What are the genotypes of the affected males? _______
c) Beatrice is also a carrier and she married a man without
hemophilia. They had 3 sons and a daughter.
Use a punnett square to show the probability of producing a
son or daughter with hemophilia?
11. Draw a pedigree (include the genotypes and phenotypes of every individual) to depict the following family:
One couple has a son and a daughter with normal pigmentation. Another couple has one son and two daughters with normal
pigmentation. The daughter from the first couple has three children with the son of the second couple. Their son and one daughter
have albinism; their other daughter has normal pigmentation.
12. Caleb has a double row of eyelashes, which he inherited from his mother as a dominant trait. His mother’s father is the only
other relative to have the trait. Veronica, a woman with normal eyelashes, falls madly in love with Caleb, and they marry. Their first
child, Polly, has normal eyelashes. Now Veronica is pregnant again and hopes they will have a child who has double eyelashes.
a) Draw a pedigree of this family (include the genotypes and phenotypes).
b) What chance does a child of Veronica and Caleb have of inheriting double eyelashes?