an overview of the red blood cell disorder sickle cell anemia in medical research Sickle cell disease (scd) is the name for a group of genetic blood disorders caused by sickle hemoglobin (hb s) the 2 key features of scd are chronic hemolytic anemia and vaso-occlusion although it is fundamentally a blood disease, scd affects the entire body, and the pathophysiology begins in very early infancy.