Globin Synthesis During Erythroid Cell Maturation in α Thalrssemia

Abstract

Globin chain synthesis was examined in erythroid cells of increasing maturity, fractionated from bone marrow of two patients with hemoglobin H disease and in one a thalassemia 1 heterozygote. In contrast to β thalassemia where a gradient of α/β chain ratios increasing with erythroid cell maturation is observed, in a thalassemia the α/β chain ratio remains constant throughout maturation. This finding suggests that in a thalassemia there is no modification of the imbalance in globin chain synthesis either by increased α chain production or decreased β chain synthesis in erythroid precursors. Furthermore, the constant α/β ratio reflects a limited degree of β chain destruction, indicating that the ability of the excess β chains to associate into tetramers protects them from proteolytic digestion.