Thalassemia is the name of a group of genetic blood disorders. Hemoglobin is the oxygen-carrying component of the red blood cells. It consists of two different proteins, an alpha and a beta. If the body doesn't produce enough of either of these two proteins, the red blood cells do not form properly and cannot carry sufficient oxygen. The result is anemia that begins in early childhood and lasts throughout life.
Since thalassemia is not a single disorder but a group of related disorders that affect the human body in similar ways, it is important to understand the differences between the various types of thalassemia.
There are two forms of beta thalassemia. They are thalassemia minor and thalassemia major (which is also called Cooley's anemia).
Thalassemia minor: The individual with thalassemia minor has only one copy of the beta thalassemia gene (together with one perfectly normal beta-chain gene). The person is said to be heterozygous for beta thalassemia.
Thalassemia major: (Cooley's anemia): The child born with thalassemia major has two genes for beta thalassemia and no normal beta-chain gene. The child is homozygous for beta thalassemia. This causes a striking deficiency in beta chain production and in the production of Hb A. Thalassemia major is, therefore, a serious disease.