Genetic Control of Cell Function and Inheritance
Marsha and Clement are both carriers of sickle cell anemia, a disease that is autosomal recessive. Their first child, Amelia, does not have the disease. Marsha and Clement are planning another pregnancy, but they are concerned about their second child having the condition. Clement’s father died from complications of sickle cell disease shortly before Amelia was born.
1. Draw a Punnett square to determine the likelihood of Marsha and Clement having a baby with sickle cell anemia. What is the chance the baby will be a carrier of the disease, just like the parents?
2. Marsha suggested to the nurse at the local family planning clinic that if the baby were a boy, he might have a higher risk of developing the disease, just like his grandfather. If you were this nurse, how would you respond?
3. When Amelia, who does not have sickle cell anemia, grows up and marries someone who does have the disease, how likely will her children have the disease?