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Reviewed August 2009
What is the official name of the HBA2 gene?
The official name of this gene is “hemoglobin subunit alpha 2.”
HBA2 is the gene's official symbol. The HBA2 gene is also known by other names, listed below.
Read more about gene names and symbols on the About page.
What is the normal function of the HBA2 gene?
The HBA2 gene provides instructions for making a protein called alpha-globin. This protein is also produced from a nearly identical gene called HBA1. These two alpha-globin genes are located close together in a region of chromosome 16 known as the alpha-globin locus.
Alpha-globin is a component (subunit) of a larger protein called hemoglobin, which is the protein in red blood cells that carries oxygen to cells and tissues throughout the body. Hemoglobin is made up of four subunits: two subunits of alpha-globin and two subunits of another type of globin. Alpha-globin is a component of both fetal hemoglobin, which is active only before birth and in the newborn period, and adult hemoglobin, which is active throughout the rest of life.
Each of the four protein subunits of hemoglobin carries an iron-containing molecule called heme. Heme molecules are necessary for red blood cells to pick up oxygen in the lungs and deliver it to the body's tissues. A complete hemoglobin protein is capable of carrying four oxygen molecules at a time (one attached to each heme molecule). Oxygen attached to hemoglobin gives blood its bright red color.
How are changes in the HBA2 gene related to health conditions?
Where is the HBA2 gene located?
Cytogenetic Location: 16p13.3
Molecular Location on chromosome 16: base pairs 172,847 to 173,710
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The HBA2 gene is located on the short (p) arm of chromosome 16 at position 13.3.
More precisely, the HBA2 gene is located from base pair 172,847 to base pair 173,710 on chromosome 16.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about HBA2?
You and your healthcare professional may find the following resources about HBA2 helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
What other names do people use for the HBA2 gene or gene products?
See How are genetic conditions and genes named? in the Handbook.
Where can I find general information about genes?
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding HBA2?
allele ; anemia ; cell ; chromosome ; contiguous ; contiguous gene deletion syndrome ; cryptorchidism ; cysts ; deletion ; disability ; gene ; gene deletion ; Hb ; heme ; hemoglobin ; hepatosplenomegaly ; hydrops fetalis ; hypospadias ; inherited ; iron ; jaundice ; kidney ; locus ; microcephaly ; molecule ; oxygen ; polycystic kidney ; protein ; sclerosis ; substitution ; subunit ; syndrome ; testes ; thalassemia ; trait
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (7 links)
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.