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 2 patients with Hb H disease and in one .alpha. thalassemia 1 heterozygote. In contrast to .beta. thalassemia, where a gradient of .alpha./.beta. chain ratios increasing with erythroid cell maturation is observed, in .alpha. thalassemia, the .alpha./.beta. chain ratio remains constant throughout maturation. In .alpha. thalassemia, there is apparently no modification of the imbalance in globin chain synthesis either by increased .alpha. chain production or decreased .beta. chain synthesis in erythroid precursors. Furthermore, the constant .alpha./.beta. ratio reflects a limited degree of .beta. chain destruction, indicating that the ability of the excess .beta. chains to associate into tetramers protects them from proteolytic digestion.