5.3: Following Patterns of Inheritance in Humans
Read section 5.3 (pages 219-226) and answer the following questions-these will serve as your note for this section.
1.
What is a pedigree?
2.
Fill in the following chart identifying the symbols used in a pedigree.
Pedigree Term
Symbol Used
Pedigree Term
Male
Affected male/affected
female
Female
Deceased
male/deceased female
Mating
Generations
Identical twins
Birth order
Non-identical twins
3.
Answer the following questions given the pedigree below;
a.
b.
c.
d.
e.
4.
How many individuals are in the third generation? ______________
In which generation are the grandchildren found in? ________________
What is the sex of individual II-5? _________________
How many children do II-5 & II-6 have together? _____________
How many individuals are “affected” in the pedigree? __________
A. What is autosomal Inheritance? Which chromosomes are affected?
B. Give three examples of autosomal dominant disorders-include the chromosome #.
C. Give three examples of autosomal recessive disorders-include the chromosome #.
Symbol Used
Autosomal Dominant Inheritance: Read through this description, including Huntington disease. Follow through the pedigree (Fig.
5.12 & 5.13) and be able to identify this as an autosomal dominant trait. Make your own summary of this in the space below. Be
able to answer the Green sentence at the very bottom of page 221.
Autosomal Recessive Inheritance: Read through this description, including Cystic Fibrosis disease. Follow the pedigree (Fig. 5.14 &
5.15) and be able to identify this as an autosomal recessive trait. Make your own summary of this in the space below.
Be able to answer the “Learning check” questions at the bottom of p223#17-22
Read through pages 224-226
There are many forms of testing that can be used to identify the presence of a genetic condition. Differentiate between the types of
testing according to how they can be used.
Describe three roles a genetic counsellor may play in helping a family cope with the possibility of a genetic disease.
p227 Q. # 2-5, 7, 8