The thalassemias are a wide spectrum of disorders characterized by reduced synthesis ofone or more subunits of the globin protein, a component of Hgb. The resulting imbalancein production of globin chains reduces Hgb stability and causes hypochromia (i.e., paleRBCs due to decreased Hgb content), microcytosis (i.e., small RBCs), ineffective RBCformation, and hemolytic anemia. Clinical manifestations are diverse, ranging fromasymptomatic hypochromia and microcytosis to profound anemia leading to death in uteroor in early childhood. Most thalassemia-related deaths are due to cardiac involvement. Inthe most severe form of α-thalassemia, α-thalassemia major, affected individuals usuallydie before or shortly after birth. The most severe form of β-thalassemia is β-thalassemiamajor, also known as Cooley’s anemia