HBD

HBD
Available structures
PDB	Human UniProt search: PDBe RCSB
List of PDB id codes
	1SHR, 1SI4
Identifiers
Aliases	HBD , hemoglobin subunit delta
External IDs	OMIM: 142000; HomoloGene: 128037; GeneCards: HBD; OMA:HBD - orthologs
Gene location (Human)
Chr.	Chromosome 11 (human)
End	5,243,657 bp
RNA expression pattern
	Top expressed in
	trabecular bone; ; bone marrow; ; bone marrow cells; ; monocyte; ; blood; ; vena cava; ; endothelial cell; ; periodontal fiber; ; spleen; ; decidua;
	n/a
	More reference expression data
	n/a
Gene ontology
Molecular function	iron ion binding ; oxygen binding ; protein binding ; heme binding ; metal ion binding ; oxygen carrier activity ; peroxidase activity ; haptoglobin binding ; hemoglobin alpha binding ; organic acid binding ;
Cellular component	hemoglobin complex ; cytosol ; blood microparticle ; haptoglobin-hemoglobin complex ;
Biological process	oxygen transport ; blood coagulation ; transport ; hydrogen peroxide catabolic process ; protein heterooligomerization ; cellular oxidant detoxification ;
	Sources:Amigo / QuickGO
Orthologs
	3045
	n/a
	ENSG00000223609
	n/a
	P02042
	n/a
	NM_000519
	n/a
	NP_000510
	n/a
	Wikidata
View/Edit Human

Last updated September 25, 2024

Hemoglobin subunit delta is a protein that in humans is encoded by the HBD gene.^[3]

Function

The delta (HBD) and beta (HBB) genes are normally expressed in the adult: two alpha chains plus two beta chains constitute HbA, which in normal adult life comprises about 97% of the total hemoglobin. Two alpha chains plus two delta chains constitute HbA2, which with HbF comprises the remaining 3% of adult hemoglobin. Five beta-like globin genes are found within a 45 kb cluster on chromosome 11 in the following order: 5' - epsilon – gamma-G – gamma-A – delta – beta - 3'.^[4]

Clinical significance

Mutations in the delta-globin gene are associated with Delta-thalassemia.^[4]

Related Research Articles

Hemoglobinopathy is the medical term for a group of inherited blood disorders involving the hemoglobin, the protein of red blood cells. They are single-gene disorders and, in most cases, they are inherited as autosomal co-dominant traits.

Thalassemias are inherited blood disorders that result in abnormal hemoglobin. Symptoms depend on the type of thalassemia and can vary from none to severe. Often there is mild to severe anemia as thalassemia can affect the production of red blood cells and also affect how long the red blood cells live. Symptoms of anemia include feeling tired and having pale skin. Other symptoms of thalassemia include bone problems, an enlarged spleen, yellowish skin, pulmonary hypertension, and dark urine. Slow growth may occur in children. Symptoms and presentations of thalassemia can change over time. Older terms included Cooley's anemia and Mediterranean anemia for beta-thalassemia. These have been superseded by the terms Transfusion-Dependent Thalassemia (TDT) and non-Transfusion-Dependent Thalassemia (NTDT). Patients with TDT require regular transfusions, typically every two to five weeks. TDTs include Beta-thalassemia major, nondeletional HbH disease, survived Hb Bart's disease, and severe HbE/beta-thalassemia.

Hemoglobin A (HbA), also known as adult hemoglobin, hemoglobin A1 or α₂β₂, is the most common human hemoglobin tetramer, accounting for over 97% of the total red blood cell hemoglobin. Hemoglobin is an oxygen-binding protein, found in erythrocytes, which transports oxygen from the lungs to the tissues. Hemoglobin A is the most common adult form of hemoglobin and exists as a tetramer containing two alpha subunits and two beta subunits (α2β2). Hemoglobin A2 (HbA2) is a less common adult form of hemoglobin and is composed of two alpha and two delta-globin subunits. This hemoglobin makes up 1-3% of hemoglobin in adults.

Hemoglobin A2 (HbA₂) is a normal variant of hemoglobin A that consists of two alpha and two delta chains (α₂δ₂) and is found at low levels in normal human blood. Hemoglobin A2 may be increased in beta thalassemia or in people who are heterozygous for the beta thalassemia gene.

Alpha-thalassemia is a form of thalassemia involving the genes HBA1 and HBA2. Thalassemias are a group of inherited blood conditions which result in the impaired production of hemoglobin, the molecule that carries oxygen in the blood. Normal hemoglobin consists of two alpha chains and two beta chains; in alpha-thalassemia, there is a quantitative decrease in the amount of alpha chains, resulting in fewer normal hemoglobin molecules. Furthermore, alpha-thalassemia leads to the production of unstable beta globin molecules which cause increased red blood cell destruction. The degree of impairment is based on which clinical phenotype is present.

The human β-globin locus is composed of five genes located on a short region of chromosome 11, responsible for the creation of the beta parts of the oxygen transport protein Haemoglobin. This locus contains not only the beta globin gene but also delta, gamma-A, gamma-G, and epsilon globin. Expression of all of these genes is controlled by single locus control region (LCR), and the genes are differentially expressed throughout development.

Hemoglobin subunit beta is a globin protein, coded for by the HBB gene, which along with alpha globin (HBA), makes up the most common form of haemoglobin in adult humans, hemoglobin A (HbA). It is 147 amino acids long and has a molecular weight of 15,867 Da. Normal adult human HbA is a heterotetramer consisting of two alpha chains and two beta chains.

Hemoglobin variants are different types of hemoglobin molecules, by different combinations of its subunits and/or mutations thereof. Hemoglobin variants are a part of the normal embryonic and fetal development. They may also be pathologic mutant forms of hemoglobin in a population, caused by variations in genetics. Some well-known hemoglobin variants, such as sickle-cell anemia, are responsible for diseases and are considered hemoglobinopathies. Other variants cause no detectable pathology, and are thus considered non-pathological variants.

Krueppel-like factor 1 is a protein that in humans is encoded by the KLF1 gene. The gene for KLF1 is on the human chromosome 19 and on mouse chromosome 8. Krueppel-like factor 1 is a transcription factor that is necessary for the proper maturation of erythroid cells.

Hemoglobin subunit alpha, Hemoglobin, alpha 1, is a hemoglobin protein that in humans is encoded by the HBA1 gene.

Hemoglobin subunit gamma-2 is a protein that in humans is encoded by the HBG2 gene.

Hemoglobin subunit gamma-1 is a protein that in humans is encoded by the HBG1 gene.

Hemoglobin subunit epsilon is a protein that in humans is encoded by the HBE1 gene.

Hemoglobin subunit zeta is a protein that in humans is encoded by the HBZ gene.

Hemoglobin subunit theta-1 is a protein that in humans is encoded by the HBQ1 gene.

Delta-beta thalassemia is a rare form of thalassemia in which there is a reduced production of hemoglobin subunit delta and hemoglobin subunit beta and raised levels of hemoglobin subunit gamma. It is an autosomal recessive disorder.

Hemoglobin, alpha 2 also known as HBA2 is a gene that in humans codes for the alpha globin chain of hemoglobin.

Mu hemoglobin is a predicted protein encoded in the HBM gene. The mRNA is expressed at moderate levels, but the protein has not been detected by mass spectrometry. The order of genes is: 5' - zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 - alpha-1 - theta1 - 3'.

<span class="mw-page-title-main">Hemoglobin Lepore syndrome</span> Medical condition

Hemoglobin Lepore syndrome is typically an asymptomatic hemoglobinopathy, which is caused by an autosomal recessive genetic mutation. The Hb Lepore variant, consisting of two normal alpha globin chains (HBA) and two delta-beta globin fusion chains which occurs due to a "crossover" between the delta (HBD) and beta globin (HBB) gene loci during meiosis and was first identified in the Lepore family, an Italian-American family, in 1958. There are three varieties of Hb Lepore, Washington, Baltimore and Hollandia. All three varieties show similar electrophoretic and chromatographic properties and hematological findings bear close resemblance to those of the beta-thalassemia trait; a blood disorder that reduces the production of the iron-containing protein hemoglobin which carries oxygen to cells and which may cause anemia.

Hemoglobin H disease, also called alpha-thalassemia intermedia, is a disease affecting hemoglobin, the oxygen carrying molecule within red blood cells. It is a form of Alpha-thalassemia which most commonly occurs due to deletion of 3 out of 4 of the α-globin genes.