Hemoglobin subunit zeta (HBZ) is belongs to the globin family. Zeta-globin is alpha-like hemoglobin. The HBZ polypeptide is synthesized in the yolk sac of the early embryo, while alpha-globin is produced throughout fetal and adult life. The HBZ gene includes five functional genes and two pseudogenes. The order of genes is: 5' - zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 -alpha-1 - theta1 - 3'.