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Related to beta thalassemia: Alpha Thalassemia
thalassemia due to one of two or more genes that depress (partially or completely) synthesis of β-globin chains by the chromosome bearing the abnormal gene. Heterozygous state (A2 t.): thalassemia minor with Hb A2 increased, Hb F normal or variably increased, Hb A normal or slightly reduced. Homozygous state: thalassemia major with Hb A reduced to very low but variable levels, Hb F very high level.