Hb S-β-thalassemia: molecular, hematological and clinical comparisons

Hemoglobin. 2011;35(1):1-12. doi: 10.3109/03630269.2010.546306.


Clinical and hematological features are presented for 261 patients with identified β-thalassemia (β-thal) mutations. Mutations causing Hb S [β6(A3)Glu→Val]-β(0)-thal were IVS-II-849 (A>G) in 44%, frameshift codon (FSC) 6 (-A) in 14%, Hb Monroe [β30(B12)Arg→Thr] in 14%, and IVS-II-1 (G>A) in 10%. Mutations causing Hb S-β(+)-thal with 14-25% Hb A (type III) were -29 (A>G) mutation in 60%, -88 (C>T) in 22% and the polyadenylation signal site (polyA) (T>C) mutation in 14%, and in Hb S-β(+)-thal with 1-7% Hb A (type I), all had the IVS-I-5 (G>C) mutation. Hematologically, only minor differences occurred between the four Hb S-β(0)-thal mutations, but among the three mutations causing Hb S-β(+)-thal type III, levels of Hb A(2), Hb F, hemoglobin (Hb), MCV and MCH were highest in the -88 and lowest in the polyA mutations. Clinically, Hb S-β(0)-thal and Hb S-β(+)-thal type I were generally severe, and Hb S-β(+)-thal type III disease with the -88 mutation was milder than that caused by the polyA mutation.

MeSH terms

  • Adult
  • Anemia, Sickle Cell / genetics
  • Anemia, Sickle Cell / mortality
  • Anemia, Sickle Cell / physiopathology
  • Child
  • Codon
  • Fetal Hemoglobin / genetics
  • Genetic Association Studies
  • Hematologic Tests
  • Hemoglobin A2 / genetics
  • Hemoglobins, Abnormal / genetics
  • Humans
  • Infant, Newborn
  • Mutation
  • Neonatal Screening
  • Sequence Analysis, DNA
  • Survival Rate
  • beta-Thalassemia / genetics*
  • beta-Thalassemia / mortality
  • beta-Thalassemia / physiopathology


  • Codon
  • Hemoglobins, Abnormal
  • Hemoglobin A2
  • Fetal Hemoglobin