Colton antigen system
Encyclopedia
The Colton antigen system (Co) is present on the membranes of red blood cells and in the tubules of the kidney
and helps determine a person's blood type
. The Co antigen
is found on a protein
called aquaporin-1 which is responsible for water homeostasis
and urine concentration.
The Co antigen is important in transfusion medicine
. 99.8% of people possess the Co(a) allele
. Individuals with Co(b) allele or who are missing the Colton antigen are at risk for a transfusion reaction such as hemolytic anemia
or alloimmunization
. Antibodies against the Colton antigen may also cause hemolytic disease of the newborn
, in which a pregnant woman's body creates antibodies against the blood of her fetus, leading to destruction of the fetal blood cells.
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
and helps determine a person's blood type
Blood type
A blood type is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells . These antigens may be proteins, carbohydrates, glycoproteins, or glycolipids, depending on the blood group system...
. The Co antigen
Antigen
An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...
is found on a protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
called aquaporin-1 which is responsible for water homeostasis
Homeostasis
Homeostasis is the property of a system that regulates its internal environment and tends to maintain a stable, constant condition of properties like temperature or pH...
and urine concentration.
The Co antigen is important in transfusion medicine
Transfusion medicine
Transfusion medicine is the branch of medicine that is concerned with the transfusion of blood and blood components. The blood bank is the section of the clinical laboratory where medical technologists process and distribute blood products under the supervision of a medical director, often...
. 99.8% of people possess the Co(a) allele
Allele
An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...
. Individuals with Co(b) allele or who are missing the Colton antigen are at risk for a transfusion reaction such as hemolytic anemia
Hemolytic anemia
Hemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells , either in the blood vessels or elsewhere in the human body . It has numerous possible causes, ranging from relatively harmless to life-threatening...
or alloimmunization
Alloimmunity
Alloimmunity is a condition in which the body gains immunity against antigens of another individual of the same species, which are perceived as foreign....
. Antibodies against the Colton antigen may also cause hemolytic disease of the newborn
Hemolytic disease of the newborn
Hemolytic disease of the newborn, also known as hemolytic disease of the fetus and newborn, HDN, HDFN, or erythroblastosis fetalis, is an alloimmune condition that develops in a fetus, when the IgG molecules produced by the mother pass through the placenta...
, in which a pregnant woman's body creates antibodies against the blood of her fetus, leading to destruction of the fetal blood cells.
External links
- Colton at BGMUTBGMUTThe BGMUT Database documents allelic variations in the genes encoding for human blood group systems. It was set up in 1999 through an initiative of the Human Genome Variation Society . Since 2006, it has been a part of the dbRBC resource of NCBI at the NIH...
Blood Group Antigen Gene Mutation Database at NCBINational Center for Biotechnology InformationThe National Center for Biotechnology Information is part of the United States National Library of Medicine , a branch of the National Institutes of Health. The NCBI is located in Bethesda, Maryland and was founded in 1988 through legislation sponsored by Senator Claude Pepper...
, NIH