1. Autosomal Dominance Inheritance

2. What’s an Autosome? Autosome: Non sex chromosome
Ex: Autosomal disorders: gene for the disease is found on chromosomes 1-22
Autosomal Recessive Inheritance
Must inherit two copies of the disorder to be affected
Healthy is dominant (HH or Hh)
Disease is recessive (hh)
Ex: Cystic fibrosis, PKU, Albinism, Sickle cell anemia
Autosomal Dominance Inheritance
Only need to inherit one copy of the disorder to be affected
Disease is dominant (HH or Hh)
Healthy is recessive (hh)
Ex: Familial hypercholesterolemia (also called FH), Huntington’s disease, Neurofibromatosis

3. Autosomal Dominance Inheritance
Disease is dominant (HH or Hh)
Homozygous dominant: early death and don’t survive to reproduce
Heterozygous live into adulthood
Healthy is recessive (hh)
ex: Paul has familial hypercholesterolemia and Stacy is healthy. The two have 3 children. After testing, the middle child is the only healthy child. Hh hh h h
Paul
Stacy H h H h
Key
H = FH disease
h= healthy H
disease
disease Hh hh Hh h h h h h
healthy
healthy

4. Video about Huntington's disease
Autosomal dominant disorder
Brain cells start to die in late 30’s
Causes uncontrollable muscle jerking
Death usually in 40’s-50’s
No treatments
Click if YouTube video doesn’t work

5. Autosomal Dominance Inheritance
Disease is dominant (HH or Hh)
Homozygous dominant: early death and don’t survive to reproduce
Heterozygous live into adulthood
Healthy is recessive (hh)
Huntington’s disease is a dominant disorder found on chromosome 4. Betty and Marcus met at a support clinic they have been attending to help them cope with the knowledge of their illness with Huntington’s disease. They would like to know the risk of having a healthy child, now that Betty is pregnant. H h Hh Hh
Marcus
Betty H H H h
Key
H = Huntington’s disease
h = healthy H
Disease (severe)
disease ? H h h h h
disease
healthy

6. Woody Guthrie: This Land is Made for You and Me

7. Review
How are autosomal dominant disorders different from autosomal recessive disorders?
What are the possible genotypes of someone with an autosomal dominant disorder?
In all likelihood, what is the genotype of an adult with an autosomal dominant disorder?
Complete a pedigree from the following story:
Jerome is concerned about Huntington’s disease (HD) since his father recently passed away due from the disorder. After a gene test, he is found to not have the HD gene. He marries Raquel and they are now preparing for their first child.
What is the likelihood of the child having HD if Raquel is healthy?
What is the likelihood of the child having HD if Raquel has HD?