39 Normal Hemoglobin Structure
Michelle To and Valentin Villatoro
Location of globin genes:1
Chromosome 16: α globin genes
Chromosome 11: β globin genes
One α globin gene and one β globin gene are inherited from each parent.
Normal hemoglobin A is made up of two α globin chains, two β globin chains, and four heme molecules.
Heme is formed from protoporphyrin ring precurosors and ferrous iron (Fe2+).
Table #1 Normal hemoglobin content at various stages of life.1
|
Embryonic: Hb Gower I (ζ2ε2) Hb Gower II (α2ε2) Hb Portland (ζ2γ2) |
Fetal: HbF (α2γ2) |
Adult: HbA (α2β2) >95% HbA2 (α2δ2) <3.5% HbF (α2γ2) 1-2% |
References:
1. Keohane EM. Hemoglobin metabolism. In: Rodak’s hematology clinical applications and principles. 5th ed. St. Louis, Missouri: Saunders; 2015. p. 124-36.
