A blood disorder that is passed down in families through genes.

Thalassemia causes the body to have less of the protein hemoglobin than usual. Hemoglobin allows red blood cells to carry oxygen. Not having enough hemoglobin or red blood cells can lead to a condition called anemia.

There are different types of thalassemia. The symptoms depend on the type and how serious it is. Symptoms of severe thalassemia can include tiredness, weakness, slow growth in children, and changes in facial bones. Some babies show symptoms of thalassemia at birth. Others get symptoms during their first two years. Some people have no symptoms.

A mild type of thalassemia, called thalassemia trait, does not need any specific treatment. With worse types, frequent blood transfusions and medicine to remove extra iron from the blood may be needed. Stem cell transplants may be an option for some children with thalassemia. This procedure can get rid of the need for lifelong blood transfusions.