Name:
Date:
HUMAN PEDIGREE WS
Per.:
II
Standards: Genetics 2e, 2f, 2g, 3a, and 3c
Objectives:
 Students should be able to interpret a human pedigree.
 Students shall be able trace x-linked traits through a pedigree.
Instructions: The pedigree is NOT correct!
You will need to shade in the males and females correctly with the information
already given (Hint: Work bottom –up. #7 has been filled in, but you will need
to ½ shade in her circle.
 Try to make the family as HEALTHY as possible 
1. Using a Punnett Square cross a normal male with a carrier female.
#21-18
a. Males genotype
XHY
b. % Hemophilia =
25%
c. % Normal =
75%
x
XHXh
Genotype
Female genotype
XHXH
XHXh
XHY
XhY
Genotype
1.
X HX h
“Carrier”
10. XHY
2.
XhY
Affected
11. XHXh
3.
X HY
4.
X HX h
“Carrier”
13. XHXh
5.
XhY
Affected
14. XHY
6.
X HX H
7.
X HX h
8.
9.



“Carrier”

12. XHY
“Carrier”

15. XhXh
Affected
“Carrier”
16. XhY
Affected
XhY
Affected
17. XhY
Affected
X HX h
“Carrier”
18. XHXH

STOP! Do not answer the following until question #21-18 has been
completed! Be sure all people in the pedigree are accounted for.
3.
5
(#) How many marriages?
4.
Male
XY represents?
5.
4
(#) How many XHY?
6.
5
(#) How many XhY (Men with hemophilia)?
7.
Female
XX represents?
8.
2
(#) How many XHXH?
9.
6
(#) How many XHXh “CARRIERS”?
10.
1
(#) How many XhXh (Women with hemophilia)?
BONUS: In your own words describe why hemophilic males can only pass
their sex-linked trait to their daughters? XhY Fathers only have a single X
chromosome to give out creating a female (daughter). If the male gave out
the Y chromosome he would automatically have a male (son).