Possible genotypes of a child of two parents with sickle cell trait

This Punnett square diagram illustrates possible genotypes for a child of two parents with sickle cell trait. The likelihood of having a child with sickle cell disease is approximately 50%. The likelihood of having a child with sickle cell anemia is approximately 25%. Other genotypes are possible for children of parents with sickle cell anemia (homozygous HbSS) or other forms of sickle cell disease such as sickle-beta-thalassemia or hemoglobin sickle cell disease.