Hemoglobin S

**Semantic type:** Amino Acid, Peptide, or Protein

**Definition:** A tetrameric complex of 2 molecules of hemoglobin subunit alpha (encoded by either the HBA1 or HBA2 gene) and 2 molecules of a hemoglobin subunit beta variant where the glutamic acid residue at position 7 has been replaced by valine.

**Synonyms:** - Hb S - HbS - Hgb S