1. Take out pedigree homework
Discuss with your group the trait you chose, and what you found out about your family!
Be ready to share!!!!

2. Pedigrees

3. What is a pedigree
Family tree used to track genetic disorders/abnormalities
Can be used to determine the mode of inheritance for a particular disorder

4. Pedigree symbols

5. Determining inheritance patterns
Autosomal inheritance
Sex-linked inheritance

6. Autosomal inheritance
controlled by a gene on an autosome (chromosomes 1-22)
Autosomal dominant
Males and females are affected equally
Many individuals are affected
Affected child MUST have an affected parent
No carriers
Autosomal recessive
Males and females affected equally
Two affected parents will always have an affected child
Normal parents can have an affected child
Has carriers

7. Sex-linked inheritance
X-linked recessive
Affects more males than females
Many females are carriers
Males CANNOT be carriers
X-linked dominant
No carriers (male or female)
All daughters of an affected male and a normal female are affected
All sons of an affected male and a normal female are affected
Y-linked
Affects only males
Either have it or you don’t