Further evidence of a quantitative deficiency of chain-specific globin mRNA in the thalassemia syndromes.

Formamide gel electrophoresis separates the mRNA fraction from reticulocyte polyribosomes of adult humans into two major RNA species with migratory rates identical to those of the alpha- and beta-globin mRNAs of the rabbit. That these two RNAs of human origin are the globin mRNAs is further supported by the deficiency of the presumed beta mRNA in reticulocyte polyribosomes of fetuses and premature infants, whose cells make gamma chains in preference to beta chains. The globin mRNAs of reticulocyte polyribosomes from patients with hematological disorders were estimated by scanning the stained formamide gels. In contrast to individuals with either hemolytic anemia without hemoglobinopathy or sickle cell anemia who had beta mRNA to alpha mRNA ratios of approximately one, a patient with Hb S-beta-thalassemia had a ratio of beta mRNA to alpha mRNA of 0.75 while two subjects with homozygous beta-thalassemia had severe deficiencies of beta mRNA. Conversely, a patient with alpha-thalassemia (Hb H disease) had a ratio of beta mRNA to alpha mRNA on reticulocyte polyribosomes of 6. These data provide further evidence of a quantitative deficiency of chain-specific globin mRNA in patients with the thalassemia syndromes.