Common haplotype dependency of high G gamma-globin gene expression and high Hb F levels in beta-thalassemia and sickle cell anemia patients

Proc Natl Acad Sci U S A. 1985 Apr;82(7):2111-4. doi: 10.1073/pnas.82.7.2111.


We have studied 42 homozygous beta-thalassemia patients from Algeria and 34 sickle cell anemia patients from Senegal and Benin, determining the relationship between haplotypes, Hb F, and G gamma-globin/A gamma-globin ratios. Populations selected have a high frequency of haplotype homozygotes because of consanguinity (Algeria) and geographic homogeneity (West Africa). We find in beta-thalassemia patients, that haplotype IX in haplotypic homozygotes and heterozygotes, haplotype III in heterozygotes, and the Senegal haplotype in sickle cell anemia patients are all linked to high G gamma-globin expression. In addition, haplotypes IX and Senegal, but not haplotype III, have high Hb F levels. All of these haplotype have a common subhaplotype (+- ) in the gamma-globin gene region. In addition, haplotypes IX, III, and Senegalese sickle cell anemia patients exhibit hematological amelioration of their disease. Conversely, haplotypes I, V, and A in thalassemia patients, which also have a common subhaplotype (-----), and the Benin subhaplotype (--++-) in sickle cell anemia patients are all associated with low G gamma-globin and low Hb F levels. Low G gamma-globin expression in the adult is associated with two haplotypes that are not common between thalassemia and sickle cell anemia patients. We conclude that the determinant for high G gamma-globin expression is haplotype-linked to common and genetically dominant subhaplotypes in the two diseases. The total Hb F level, unlike the high G gamma-globin expression, however, is linked to haplotypes but not to subhaplotypes, thus dissociating the two genetic effects.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Anemia, Sickle Cell / genetics*
  • Child, Preschool
  • Fetal Hemoglobin / analysis*
  • Gene Expression Regulation*
  • Globins / genetics*
  • Humans
  • Infant
  • Thalassemia / genetics*


  • Globins
  • Fetal Hemoglobin