Hemoglobin subunit gamma 1 and 2 promoter DNA (HBG1/2 promoter)

The Hemoglobin subunit gamma 1 and 2 (HBG1/2) promoter DNA is a critical regulatory region responsible for the expression of fetal hemoglobin (HbF). During the transition from fetal to postnatal life, the expression of gamma-globin is silenced by the binding of repressor proteins, such as BCL11A and ZBTB7A (also known as LRF), to specific motifs within these promoters, facilitating the switch to adult beta-globin (Nature Medicine, 2022). In hemoglobinopathies like sickle cell disease and beta-thalassemia, the reactivation of HbF can mitigate the clinical symptoms caused by defective or absent adult beta-globin by preventing the polymerization of sickle hemoglobin and providing functional oxygen transport (NIH, 2023). Modern therapeutic approaches utilize genome editing technologies, including CRISPR-Cas12a and base editors, to target the HBG1/2 promoter directly. By disrupting repressor binding sites or mimicking naturally occurring mutations associated with Hereditary Persistence of Fetal Hemoglobin (HPFH), these therapies enable sustained gamma-globin production and the formation of functional HbF in adult erythroid cells (Editas Medicine, 2023; Beam Therapeutics, 2024).

Other names

Gamma-globin promoterHBG1/HBG2 promoter regionFetal hemoglobin promoterHBG1 promoterHBG2 promoter

Disruption of repressor binding sites (e.g., BCL11A or ZBTB7A motifs) or introduction of HPFH-like mutations via genome editing to induce fetal hemoglobin (HbF) expression.