Beta-globin is part of a larger part of a protein found in red blood cells. This larger protein, hemoglobin, is what helps carry oxygen throughout the body. If the hemoglobin is not formed correctly, or at all, it affects the amount of red cells that are available for the body to use and how oxygen is distributed to the body. There are two major genetic disorders that are associated with beta-globin. The first is sickle cell disease, which affects the formation of hemoglobin and changes the shape of red blood cells from their normal circular shape to a half-moon/crescent shape. It is an inherited disorder characterized by anemia, joint pain, and a shortage of red blood cells. In some individuals with sickle cell disease their organs such as their lungs, liver and kidneys may be damaged. The amount of the pain, organ damage, and swelling varies among individuals with sickle cell disease. The second disorder is beta-thalassemia (BT), where the production of beta-globin is decreased, thus affecting the function of hemoglobin. This causes a lack of oxygen and iron buildup inside the body. Effects of the more severe form of BT, thalassemia major (Cooley’s anemia) can be seen within the first six months to 2 years of age. Children affected with BT fail to gain weight or grow at normal rates, may have diarrhea, enlarged organs, or irritability. Symptoms of the less severe form of BT, thalassemia intermedia, typically appear anytime from childhood into adulthood. They tend to be similar to those of thalassemia major, but milder. Chelation therapy and blood transfusions are necessary for those more severely affected for normal growth and development, but may only be needed on occasion for those mildly affected individuals. Life expectancy for sickle cell disease and beta-thalassemia is variable, but can be prolonged with proper treatment and management. Both genetic conditions are caused by mutations in the HBB gene.