Autosomal Dominance Inheritance

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. Autosomal Dominance Inheritance • 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. Hh Hh H h Marcus Betty H H H h Key H = Huntington’s disease h = healthy H Disease (severe) disease ? H h h h h disease healthy

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

6. 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