The mechanism sees that<unk> assemias results in decreased<unk> -globin production, therefore fewer<unk> -globin chains are produced, resulting in an excess of β chains in adults and excess γ chains in newborns. The excess β chains form unstable tetramers called hemoglobin H or HbH of four beta chains. The excess γ chains form tetramers which are poor carriers of O2 since their affinity for O2 is too high, so it is not dissociated in the periphery. Homozygote α0<unk> assaemias, where numerous γ4 but no α-globins occur at all (referred to as Hb Barts), often result in death soon after birth.
Alpha-thalassemia
Thalassemia
Beta thalassemia
Delta-beta thalassemia
Hereditary spherocytosis
Hemoglobinemia
Paroxysmal nocturnal hemoglobinuria
Sideroblastic anemia