Name ________________________________________
Assignment #____
Pedigree and Karyotype Review
1. Below is a pedigree for an inherited lung disease. Provide the genotypes of each of the individuals marked
with lower case letters.
2. Below is a pedigree for an inherited brain disease. Provide the genotypes of each of the individuals marked
with lower case letters.
3. Use the pedigree below to answer the following questions.
Shaded individuals have Achondroplasia
a. Write the generation on the pedigree numbers (roman numerals).
b. How many children did individuals I-1 and I-2 have? ________________________________
c. Is achondroplasia caused by a dominant or recessive trait? _______________
d. Is achondroplasia autosomal or sexlinked? ________________________________________
e. Write the genotypes of each individual on the pedigree.
4. Use the Pedigree for Trait A to determine the genetic basis of this trait.
a. Does a dominant or recessive allele produce the trait? Explain.
b. Is it autosomal or sex-linked? Explain.
c. What are the genotypes of all the individuals in the pedigree? (Write them on the pedigree.)
d. What is the genotype of individual IV-2? Explain.
e. What is the genotype of individual IV-6? Explain.
f. What is the genotype of individual I-1? Explain.
5. Use the information provided below to create a pedigree. Then answer the question at the end of each
description.
a. The ability to roll your tongue is dominant to not being able to roll your tongue. Draw a pedigree to show the
inheritance of this trait, given the following family history:
Grandpa Snow is a tongue roller but Grandma Snow is not. They have four children (2 sons and 2 daughters)
who are all rollers. Their last daughter, Judy, married John Flake. John’s parents are both rollers, but John’s two
sisters are non-rollers. John is a roller. John and Judy Snow-Flake have three children named Crystal SnowFlake (a non-roller), Pretty Snow-Flake (a roller) and Jake Snow-Flake (a roller).
b. A man and woman marry. They have five children, 2 girls and 3 boys. The mother is a carrier of hemophilia,
an X-linked disorder. She passes the gene on to two of the boys who died in childhood and one of the daughters
is also a carrier. Both daughters marry men without hemophilia and have 3 children (2 boys and a girl).
The carrier daughter has one son with hemophilia. One of the non-carrier daughter's sons marries a woman who
is a carrier and they have twin daughters.
What is the percent chance that each daughter will also be a carrier?
Making Conclusions
15. If a child has an autosomal dominant trait, what can you say about the parents?
16. If two parents have an autosomal dominant trait, what can you say about their children?
17. If two parents have an autosomal recessive trait, what can you say about their children?
18. If two parents do not have an autosomal recessive trait, what can you say about their children?
19. Can autosomal recessive traits skip generations?
20. If a woman has a sexlinked trait, what conclusion can be made about her sons?
Karyotype Activity
Part A: Analysis of a “Normal” Karyotype
Observe the karyotype below. Notice the following:
.The banding patterns, size, and general shape are identical for each of the homologous pairs of
chromosomes. The homologous pairs of chromosomes are arranged by sized and then numbered from 1-23.
This is to make the analysis easier.
Gender = _____________________
Explain why you know this is the gender. ______________________________________________________________
________________________________________________________________________________________________
Part B: “What’s Wrong with my Karyotype?”
For each of the given karyotypes complete the following steps:
1.Identify: Next to each karyotype, identify it as either normal or abnormal. If the karyotpye is normal skip to step #3.
2.Abnormality: If the karyotype is abnormal, circle the abnormality in the karyotype. Then explain what is wrong with
the karyotype, and where the abnormality is located specifically on the chromosome. You will be looking for missing
chromosomes and/or parts of chromosomes, extra chromosomes and/or parts, or anything that makes the karyotype
abnormal or different from the normal karyotype above with the exception of the 23rd pair of chromosomes.
3.Gender: Identify the karyotype as male or female.
Karyotype #1
Is the karyotype normal or abnormal?________________
If abnormal, what is wrong in this karyotype?
And where specifically is the abnormality located in the karyotype?
The gender of the karyotype is.
Karyotype #2
Is the karyotype normal or abnormal?____________________________
If abnormal, what is wrong in this karyotype?
And where specifically is the abnormality located in the
karyotype?
The gender of the karyotype is.
Karyotype #3
Is the karyotype normal or abnormal?___________________
If abnormal, what is wrong in this karyotype?
Where specifically is the abnormality located in the karyotype?
The gender of the karyotype is.
Karyotype #4
Is the karyotype normal or abnormal?____________________________
If abnormal, what is wrong in this karyotype?
Where specifically is the abnormality located in the
karyotype?
The gender of the karyotype is.
Karyotype #5
Is the karyotype normal or abnormal?____________________________
If abnormal, what is wrong in this karyotype?
Where specifically is the abnormality located in the
karyotype?
The gender of the karyotype is.
Karyotype #6
Is the karyotype normal or abnormal?____________________________
If abnormal, what is wrong in this karyotype?
Where specifically is the abnormality located in the
karyotype?
The gender of the karyotype is.
.
Part C: Analysis Questions
1. How many autosomes are in a normal human karyotype? ______________________
2. If you had your own karyotype in front of you, what kind of sex chromosomes would you see? ____________
3.Explain the following statement: The human male determines the sex of all of his offspring.
BONUS: Now go back to karyotypes #1-6 in Part B and identify the genetic abnormality by name. If there are NO
abnormalities in the karyotype write “normal” on the line.
Karyotype #1 _____________________________
Karyotype #4 ___________________________________
Karyotype #2 _____________________________
Karyotype #5 ___________________________________
Karyotype #3 _____________________________
Karyotype #6 ___________________________________