9. PLEASE READ THIS: SICKLE CELL ANEMIA Sickle cell anemia is a blood disorder that affects hemoglobin (pronounced: hee -muh-glow-bin), the protein found in red blood cells (RBCs) that helps carry oxygen throughout the body. Sickle cell anemia occurs when a person inherits two abnormal genes (one from each parent) that cause their RBCs to change shape. Instead of being flexible and disc-shaped, these cells are more stiff and curved in the shape of the old farm tool known as a sickle — that's where the disease gets its name. The shape is similar to a crescent moon. Red blood cells with normal hemoglobin ( hemoglobin A , or HbA ) move easily through the bloodstream, delivering oxygen to all of the cells of the body. Abnormal RBC’s may occlude blood vessels and this is precipitated by infection, dehydration and stress.