Alpha thalassemia is a blood disorder. The thalassemias are a group of disorders that have a single feature in common: they all have a genetic defect in the production of hemoglobin, and thus produce a form of anemia. The problem in the thalassemias is with globin production. The thalassemias are classified according to the type of globin polypeptide chain that is underproduced. The alpha chain is involved in alpha thalassemia (and the beta chain is affected in the more familiar beta thalassemia).