The Effect of Amelioration of Anemia on the Synthesis of Fetal Hemoglobin in Sickle Cell Anemia.

By L. JUDEN REED, THOMAS B. BRADLEY, JR. AND HEu N M. RANNEY F ETAL HEMOGLOBIN, a tetramer of 2a and 2y polypeptide chains, constitutes the major hemoglobin component in newborn infants. During the first 6 months of extra-uterine life, the synthesis of y chains declines as chain synthesis increases. Adult Hb A, a tetramer of 2a and 2$ polypeptide chain accounts for over 95 per cent of the hemoglobin of most normal children at one year of age.’ In certain hereditary disorders of hemoglobin synthesis, e.g., sickle cell anemia and thalassemia major, the synthesis of y chains is not completely suppressed, and appreciable amounts of fetal hemoglobin may be found in the red cells of adults with these diseases.2 In occasional patients with acquired hematologic disorders,3’4 e.g., aplastic anemia or leukemia, the synthesis of y chains is apparently resumed, and some erythrocytes containing Hb F appear in the circulation. Except for individuals with the curious genetic anomaly designated “hereditary persistence of hemoglobin F”5 adults in whom Hb F synthesis persists or