GeneID: 9


Common Name: δ Type: Gene
Chromosome: 11 (NC_000011.10) Locus: NG_000007.3 (β-locus)
HUGO Symbol: HBD Full Name: hemoglobin subunit delta
Exons: 3 Introns: 2

The delta- (HBD) and beta- (HBB) globin genes are normally expressed in the adult. The combination of two alpha chains plus two beta chains constitutes HbA (α2β2), which in normal adult life comprises about 97% of total hemoglobin. Two alpha chains plus two delta chains constitute HbA2 (α2δ2), which together with HbF (fetal hemoglobin; α2γ2) comprises the remaining 3% of adult hemoglobin. The order of the genes in the beta-globin cluster is: 5'-ε(HBE)-Gγ(HBG2)-Aγ(HBG1)-ψβ(HBBP1)-δ(HBD)-β(HBB)-3'. Mutations in the delta-globin gene (HBD) are associated with beta-thalassemia. A mutation that prevents formation of any delta chains is termed a delta0 mutation. One that decreases but does not eliminate the production of delta chain is termed a delta+ mutation. When a person inherits two delta0 mutations, no HBA2 is produced. Hematologically, however, this is innocuous since only 2-3% of the normal adult hemoglobin is HBA2. Therefore, that person will have normal hematological parameters (erythrocyte count, total hemoglobin, mean corpuscular volume, red cell distribution width). Individuals who inherit only one delta thalassemia mutation gene will have a decreased HBA2 without any abnormal hematological consequences.

Synonyms: Delta-globin


Number of entries/variants: 275


Publications / Origin

  1. Spritz RA, DeRiel JK, Forget BG, Weissman SM, Complete nucleotide sequence of the human delta-globin gene., Cell , 21(3), 639-46, 1980
  2. De Angioletti M, Lacerra G, Gaudiano C, Mastrolonardo G, Pagano L, Mastrullo L, Masciandaro S, Carestia C, Epidemiology of the delta globin alleles in southern Italy shows complex molecular, genetic, and phenotypic features., Human mutation, 20(5), 358-67, 2002
  3. Bouva MJ, Harteveld CL, van Delft P, Giordano PC, Known and new delta globin gene mutations and their diagnostic significance., Haematologica, 91(1), 129-32, 2006
Created on 2014-04-01 14:19:10, Last reviewed on 2016-04-28 11:02:10 (Show full history)

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