Globin biosynthesis in sickle cell, Hb SC, and Hb C diseases.
The wide range of globin synthesis ratios reported in patients with sickle cell disease casts doubt on whether the presence of genes for alpha- or beta-thalassemia in combination with Hb S can be detected by globin synthesis studies. We have studied globin synthesis in 20 patients with Hb SS who had a mean betaA/alpha ratio of 1.05+/-0.04, similar to that of 28 control children. In nine of these patients the percentage of newly synthesized radioactive alpha-chains in dimer or monomer forms was 16.3%+/-1.3, also similar to the control subjects. The remainder of alpha-chain was in hemoglobin tetramer. In nine patients with Hb SC, the (non-alpha)/alpha ratio was 0.97+/-0.04, and the free alpha-chain pool radioactivity in four patients was 14.1%+/-4.2. In three patients with Hb CC, betac/alpha ratios were 0.99, 1.07, and 1.10. These results indicate that globin synthesis ratios and alpha-chain radioactivity in the free alpha-chain pool of peripheral blood of patients with Hb SS, Hb SC, and Hb CC have narrow ranges, close to those of nonthalassemic controls. The data provide a basis for detecting syndromes with Hb S or Hb C associated with alpha- or beta-thalassemia. This precise differentiation is important for clinical studies of severity in sickle cell disease and for genetic counseling.
D000293:Adolescent; D000328:Adult; D000755:Anemia, Sickle Cell / Q000175:diagnosis / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005914:Globins / Q000096:biosynthesis*; D006444:Hemoglobin C / Q000096:biosynthesis; D006445:Hemoglobin C Disease / Q000175:diagnosis / Q000378:metabolism*; D006451:Hemoglobin, Sickle / Q000096:biosynthesis; D006720:Homozygote; D006801:Humans; D007223:Infant; D008297:Male; D013789:Thalassemia / Q000378:metabolism
D006451:Hemoglobin, Sickle; D005914:Globins; D006444:Hemoglobin C