When BOTH parents have sickle cell trait (AS), the child may inherit:
- two normal hemoglobin genes, or
- one normal hemoglobin gene and one sickle cell gene, or
- two sickle cell genes
With EACH pregnancy there is a:
- 25% chance that the baby's red blood cells will be normal (AA).
- 50% chance that the baby will have sickle cell trait (AS).
- 25% chance that the baby will have sickle cell disease (SS).