NAME_______________________________________________________________________________PERIOD__________
ACTIVITY: KARYOTYPING
OBJECTIVES:
• Identify key elements of a karyotype
• Prepare a karyotype using a computer model
• Analyze patient karyotypes for abnormalities
• Diagnose patients using knowledge of chromosomal genetic disorders (Down
Syndrome, Klinefelter’s Syndrome, Trisomy 13 Syndrome)
• Learn chromosome abnormalities and symptoms of 4 different disorders
WEBSITE:www.biology.arizona.edu
PART I) Intro to Karyotypes
Click on HUMAN BIOLOGY, then click on WEB KARYOTYPING (top left-hand of page).
Read the INTRODUCTION page and the complete the following:
1) In humans, there are _____________ pairs of chromosomes.
2) Condensed human chromosomes are visible using a
_______________ microscope.
3) What do the dark bands (G bands) on the chromosomes ACTUALLY contain?
_____________________________________________________
4) Karyotype analysis involves comparing the ________________ of the
chromosomes, the placement of ______________________, and
_________________________________________________ of G bands.
Now that you know how karyotypes are analyzed, you will review the patient histories
of 3 patients. You will make their karyotypes and analyze their chromosomes for any
abnormalities. Finally, you’ll diagnose the patients for genetic disorders.
Time to get started—your patients are depending on you!
CLICK ON PATIENT HISTORIES to begin.
PART II) Patient Diagnoses
PATIENT A
5) Summarize Patient A’s history:
______________________________________________
______________________________________________
______________________________________________
Click on COMPLETE PATIENT A’s KARYOTYPE
You are looking at an incomplete karyotype for Patient A. Examine the
length and banding pattern for the chromosome at the top of the page. Match this
chromosome to its homologous chromosome in the karyotype.
6) How many total chromosomes are in Patient A’s karyotype (count them)? ______
7) The last set of chromosomes is the sex chromosomes, which determine gender.
Two large chromosomes (XX) indicate female. One large and one small chromosome
(XY) indicates male. What is the pair of sex chromosomes for Patient A? ______
8) Which chromosome # has an extra one? _________________
9) Review the TABLE for DIAGNOSIS & CHROMOSOMAL ABNORMALITY. What is
your diagnosis for Patient A? ______________________________________
PATIENT B
10) Summarize Patient B’s history:
___________________________________________________________
________________________________________________
_____________________________________
Click on COMPLETE PATIENT B’s KARYOTYPE
You are looking at an incomplete karyotype for Patient B. Examine the
length and banding pattern for the chromosome at the top of the page.
Match this chromosome it to its homologous chromosome in the karyotype.
11) How many total chromosomes are in Patient B’s karyotype (count them)? ______
12) The last set of chromosomes are the sex chromosomes, which determine gender.
Two large chromosomes (XX) indicate female. One large and one small chromosome
(XY) indicates male. What is the pair of sex chromosomes for Patient B? ______
13) Which chromosome # has an extra copy? _________________
14) Complete the correct notation (way of writing) for Patient B’s karyotype:
47 X _____
15) Review the TABLE for DIAGNOSIS & CHROMOSOMAL ABNORMALITY. What is
your diagnosis for Patient B? ______________________________________
PATIENT C
16) Summarize Patient C’s history:
___________________________________________________________
___________________________________________________
___________________________________________
Click on COMPLETE PATIENT C’s KARYOTYPE
You are looking at an incomplete karyotype for Patient C. Examine the length
and banding pattern for the chromosome at the top of the page. Match this
chromosome it to its homologous chromosome in the karyotype.
17) How many total chromosomes are in Patient C’s karyotype (count them)? ______
18) The last set of chromosomes are the sex chromosomes, which determine gender.
Two large chromosomes (XX) indicate female. One large and one small chromosome
(XY) indicates male. What is the pair of sex chromosomes for Patient C? ______
19) Which chromosome # has an extra one? _________________
20) Complete the correct notation (way of writing) for Patient C’s karyotype:
47 XY +_____
21) Review the TABLE for DIAGNOSIS & CHROMOSOMAL ABNORMALITY. What is
your diagnosis for Patient C? ______________________________________
PART III) MORE ABOUT CHROMOSOMAL DISORDERS
WEBSITE: http://learn.genetics.utah.edu/content/chromosomes/
22) Click on MAKE A KARYOTYPE
Create your own karyotype by clicking and dragging from the ‘pool’ of unpaired
chromosomes. Turning on HINTS is ok! When you are done, show your teacher.
Teacher initials (KARYOTYPE COMPLETE): _____
23) Click the BACK button to go back to CHROMOSOMES page. Click on USING
KARYOTYPES TO PREDICT GENETIC DISORDERS. Scroll down to the sections TOO
MANY OR TOO FEW CHROMOSOMES and MISSING PIECES. Read the information
and answer the following:
a) What is trisomy? ____________________________________________
b) What is monosomy? __________________________________________
c) What is a terminal deletion? ___________________________________
24) In the same 2 sections, click on the links to the right of the page that talk
about the various genetic disorders. Read through to learn about the disorders,
then complete the matching below.
MATCH THESE TERMS TO THE CORRECT DESCRIPTION:
Turner syndrome
Williams syndrome
Downs syndrome
Klinefelter syndrome
a. ___________________ Most common genetic disorder that is caused
by a chromosomal abnormality, affecting 1/800-1000 babies. Caused by
nondisjunction, which results in an extra copy of chromosome 21.
b. ___________________ Caused by a deletion of the elastin gene in
chromosome 7. Symptoms include heart defects and unusual facial
features.
c. ___________________ Also known as “47 XXY” because individuals with
this disorder have TWO X chromosomes and ONE Y chromosome. The
abnormality affects sexual development.
d. ___________________ Girls with this disorder are shorter than normal,
may start puberty late and have webbed necks. This disorder is caused by
a missing or incomplete X chromosome.