There are 2 main forms of Thalassemia:
Thalassemia minor occurs if you receive the faulty gene from only 1 parent. People with this form of the disorder are carriers of the disease. Most of the time, they do not have symptoms. People who have Thalassemia trait (also called Thalassemia minor) carry the genetic trait for Thalassemia but do not usually experience any health problems except perhaps a mild anemia. A person may have either alpha Thalassemia trait or beta Thalassemia trait, depending upon which form of beta protein is lacking.
Thalassemia major occurs when a child inherits two mutated genes, one from each parent. Children born with Thalassemia major usually develop the symptoms of severe anemia within the first year of life. They lack the ability to produce normal, adult hemoglobin and experience chronic fatigue. Beta Thalassemia major is also called Cooley anemia.