The Metabolism of the Individual C14 Labeled Hemoglobins in Patients with H-thalassemia, with Observations on Radiochromate Binding to the Hemoglobins during Red Cell Survival.

Patients with thalassemia may have abnormal alterations in the proportions of the structurally normal hemoglobins F and A2, or, in more rare circumstances, new hemoglobins of abnormal structure may appear. Such abnormal hemoglobins have not been shown to have substitutions of single amino acids in the polypeptide chain, as exemplified by hemoglobins S and C. Rather, they occur as unusual combinations of subunits of the hemoglobin molecule (a2/32). Thus, tetramer formation with normal polypeptide units is seen. Examples of tetramer formation in thalassemiaare hemoglobins H (,14) (1), Bart's (y4) (2), and possibly a4 (3). There is also evidence that a delta chain tetramer may be present in very small quantities (4). Fusion of pieces of the beta and delta polypeptide chains into one polypeptide unit occurs in hemoglobin Lepore (5). Investigations in this laboratory have been concerned with the manner in which the various hemoglobins are distributed among the red cells in thalassemia. Previous reports have dealt with the behavior of hemoglobins A, F, and A2 (6, 7). The present study describes the distribution of