Hemoglobin Constant Spring is a
variant of
hemoglobin
Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocyt ...
in which a
mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA replication, DNA or viral repl ...
in the
alpha globin
Hemoglobin subunit alpha, Hemoglobin, alpha 1, is a hemoglobin protein that in humans is encoded by the ''HBA1'' gene.
Gene
The human alpha globin gene cluster located on chromosome 16 spans about 30 kb and includes seven loci: 5'- zeta - pseu ...
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
produces an alpha globin chain that is abnormally long. It is the most common nondeletional
alpha-thalassemia
Alpha-thalassemia (α-thalassemia, α-thalassaemia) 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 ...
mutation associated with
hemoglobin H
Hemoglobin H disease is a type of alpha thalassemia caused by impaired production of three of the four alpha globins, coded by genes HBA1 and HBA2
Hemoglobin, alpha 2 also known as HBA2 is a gene that in humans codes for the alpha globin chain ...
disease. The quantity of hemoglobin in the cells is low because the
messenger RNA is unstable and some is degraded prior to protein synthesis. Another reason is that the Constant Spring alpha chain protein is itself unstable. The result is a thalassemic phenotype.
Hemoglobin Constant Spring is renamed after
Constant Spring district in
Jamaica
Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of His ...
.
About Thalassemia
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See also
* Hemoglobin variants
Hemoglobin variants are 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 varia ...
* Hemoglobinopathy
Hemoglobinopathy is the medical term for a group of inherited blood disorders and diseases that primarily affect red blood cells. They are single-gene disorders and, in most cases, they are inherited as autosomal co-dominant traits.
There are t ...
* Thalassemia
References
{{Reflist
Hemoglobins