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Encyclopedia > Duffy antigen
Contents

Discovery

In 1950 the Duffy antigen was discovered in a multiply transfused hemophiliac in whose serum contained the first example of anti-Fya. In 1951 the antibody to a second antigen, Fyb, was discovered in the serum of a woman who had been pregnant three times. Using these antibodies three common phenotypes were defined: Fy(a+b+), Fy(a+b-), and Fy(a-b+). Events January January 5 - US Senator Estes Kefauver introduces a resolution calling for examination of organized crime in the USA January 6 - The United Kingdom recognizes the Peoples Republic of China. ... An antigen is any molecule that is recognized by antibodies. ... Haemophilia or hemophilia is the name of any of several hereditary genetic illnesses that impair the bodys ability to control bleeding. ... Global Metrics Human security Major Armed Conflicts: Total Deaths in Battle: 700,000 people Violent Deaths caused by Government (Other than War): Violent Deaths caused by other humans: Juvenile Violent Crime: Political security Nations Holding Multi-party Elections: Percentage Living under a Fully Democratic System of Governance: Free Countries: Percentage... Schematic of antibody binding to an antigen An antibody is a protein used by the immune system to identify and neutralize foreign objects like bacteria and viruses. ... An antigen is any molecule that is recognized by antibodies. ... Blood plasma is a component of blood. ... The phenotype of an individual organism is either its total physical appearance and constitution, or a specific manifestation of a trait, such as size or eye color, that varies between individuals. ...


Genetics and genomics

The Duffy antigen gene (gp-Fy; CD234) is located on the long arm of chromosome 1 (1.q22-1.q23) and was cloned in 1993. It is a single copy gene and encodes a 336 amino acid acidic glycoprotein. The gene carries the antigenic determinants of the Duffy blood group system consisting of four alleles (FY*A and FY*B - coding for the Fya and Fyb antigens, respectively - FY*X and FY*Fy), five phenotypes and five antigens (Fy-a, Fy-b, Fy-o). Fya and Fyb differ by in a single amino acid at position 43: aspartic acid in Fya and glycine in Fyb. The genetic basis for the Fy(a-b-) phenotype is a point mutation in the erythroid specific promoter. An antigen is any molecule that is recognized by antibodies. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... Figure 1: Chromosome. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... A glycoprotein is a macromolecule composed of a protein and a carbohydrate (a sugar). ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... An antigen is any molecule that is recognized by antibodies. ... An allele is any one of a number of alternative forms of the same gene occupying a given locus (position) on a chromosome. ... The phenotype of an individual organism is either its total physical appearance and constitution, or a specific manifestation of a trait, such as size or eye color, that varies between individuals. ... An antigen is any molecule that is recognized by antibodies. ... In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ... Aspartic acid, also known as aspartate, the name of its anion, is one of the 20 natural proteinogenic amino acids which are the building blocks of proteins. ... This is an article about Glycine, the amino acid. ... The phenotype of an individual organism is either its total physical appearance and constitution, or a specific manifestation of a trait, such as size or eye color, that varies between individuals. ... A point mutation is a type of mutation that causes the replacement of a single base pair with another pair. ... for disambiguation of the term promoter, see the promoter Wiktionary article In genetics, a promoter is a DNA sequence that enables a gene to be transcribed. ...


The Duffy antigen/chemokine receptor gene (DARC) is composed of a single exon. Most Duffy negative blacks carry a silent Fy-b allele with a single T to C substitution at nucleotide -46, impairing the promoter activity in erythroid cells by disrupting a binding site for the GATA1 erythroid transcription factor. The gene is still transcribed in non erythroid cells in the presence of this mutation. Chemokines are a class of chemotactic cytokines, or small secreted protein signals. ... Receptor may refer to: In telecommunication, a receiver. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... The exon portion of a DNA strand encodes a specific portion of a protein. ... An allele is any one of a number of alternative forms of the same gene occupying a given locus (position) on a chromosome. ... A nucleotide is an organic molecule consisting of a heterocyclic nucleobase (a purine or a pyrimidine), a pentose sugar (deoxyribose in DNA or ribose in RNA), and a phosphate or polyphosphate group. ... for disambiguation of the term promoter, see the promoter Wiktionary article In genetics, a promoter is a DNA sequence that enables a gene to be transcribed. ... In molecular biology, a transcription factor is a protein that binds DNA at a specific promoter or enhancer region or site, where it regulates transcription. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... This article is about mutation in biology, for other meanings see: mutation (disambiguation). ...


Differences in the racial distribution of the Duffy antigens were discovered in 1954 when it was found that the majority of blacks had the erythrocyte phenotype Fy(a-b-): 68% in African-Americans and 88-100% in African blacks. This phenotype is exceedingly rare in whites. 1954 was a common year starting on Friday (link will take you to calendar). ... Human red blood cells Red blood cells are the most common type of blood cell and are the vertebrate bodys principal means of delivering oxygen to body tissues via the blood. ... The phenotype of an individual organism is either its total physical appearance and constitution, or a specific manifestation of a trait, such as size or eye color, that varies between individuals. ... African Americans, also known as Afro-Americans or black Americans, are an ethnic group in the United States of America whose ancestors, usually in predominant part, were indigenous to Sub-Saharan and West Africa. ... The phenotype of an individual organism is either its total physical appearance and constitution, or a specific manifestation of a trait, such as size or eye color, that varies between individuals. ...


Molecular biology

Duffy has been found to act as a multispecific receptor for chemokines of both the C-C and C-X-C families, including: MGSA, regulated upon activation normal T expressed and secreted (RANTES; CCL5), monocyte chemotatic protein-1 (MCP-1; CCL2) and the angiogenic CXC chemokines interleukin-8 (IL-8, CXCL8), growth related gene alpha (GRO-α, CXCL1), neutrophil activating peptide-2 (NAP-2, CXCL7) and ENA-78 (CXCL5). Consequently the Fy protein is also known as DARC (Duffy Antigen Receptor for Chenokines). Chemokines are a class of chemotactic cytokines, or small secreted protein signals. ... Chemokines are a class of chemotactic cytokines, or small secreted protein signals. ...


While Duffy is expressed on erythrocytes the Duffy antigen is found on some epithelial cells, Purkinje cells of the cerebellum, endothelial cells of thyroid capillaries, the post-capillary venules of some organs and the large pulmonary venules. Human red blood cells Red blood cells are the most common type of blood cell and are the vertebrate bodys principal means of delivering oxygen to body tissues via the blood. ... Cerebellum (in blue) of the human brain General Features Location: It is found at the bottom rear of the head (the hindbrain), directly above the brainstem. ... The thyroid gland and its relations In anatomy, the thyroid (IPA θaɪɹoɪd) is an endocrine gland. ... The word capillary is used to describe any very narrow tube or channel through which a fluid can pass. ...


The antigen is predicted to have 7 transmembrane domains, an exocellular N-terminal domain and an endocellular C-terminal domain. Alignment with other seven transmembrane G-protein coupled receptors shows that DARC lacks the highly conserved DRY motif in the second intracellular loop of the protein that is known to be associated with G-protein signaling. Consistent with this finding ligand binding by DARC does not induce G-protein coupled signal transduction nor a Ca2+ flux unlike other chemokine receptors. Based on these alignments the Duffy antigen is considered to be most similar to the interleukin-8B receptors. A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Chemokines are a class of chemotactic cytokines, or small secreted protein signals. ...


On erythrocytes the Duffy antigen acts as a receptor for invasion by the human malarial parasites Plasmodium vivax and Plasmodium knowlesi; Duffy negative individuals whose erythrocytes do not express the receptor are resistant to infection. This antigen may also play a role in erythrocyte invasion in the rodent malarial parasite Plasmodium yoelii. Human red blood cells Red blood cells are the most common type of blood cell and are the vertebrate bodys principal means of delivering oxygen to body tissues via the blood. ... Receptor may refer to: In telecommunication, a receiver. ... Red blood cell infected with Malaria (Italian: bad air; formerly called ague or marsh fever in English) is an infectious disease which causes about 500 million infections and 2 million deaths annually, mainly in the tropics and sub-Saharan Africa. ... Human red blood cells Red blood cells are the most common type of blood cell and are the vertebrate bodys principal means of delivering oxygen to body tissues via the blood. ... Human red blood cells Red blood cells are the most common type of blood cell and are the vertebrate bodys principal means of delivering oxygen to body tissues via the blood. ...


In DARC-transfected cells, DARC is internalized following ligand binding and this led to the hypothesis that expression of DARC on the surface of erythocytes, endothelial, neuronal cells and epithelial cells may act as a sponge and provide a mechanism by which inflammatory chemokines may be removed from circulation as well as their concentration modified in the local environment. This hypothesis has also been questioned after knock out mice were created. These animals appeared healthy and had normal responses to infection. The function of the Duffy antigen remains presently (2004)unknown. The endothelium is the layer of thin, flat cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. ... In zootomy, epithelium is a tissue composed of a layer of cells. ... Chemokines are a class of chemotactic cytokines, or small secreted protein signals. ...


External links

  • Duffy gene (http://www.dsi.univ-paris5.fr/genatlas/fiche1.php?symbol=FY)
  • Population data (http://www.genes.uchicago.edu/fri/Hamblin2002.pdf)

  Results from FactBites:
 
Duffy antigen - Wikipedia, the free encyclopedia (1775 words)
The Duffy antigen is a pair of proteins which appears on the outside of red blood cells.
In 1950 the Duffy antigen was discovered in a multiply transfused hemophiliac whose serum contained the first example of anti-Fya.
Differences in the racial distribution of the Duffy antigens were discovered in 1954 when it was found that the majority of fls had the erythrocyte phenotype Fy(a-b-): 68% in African Americans and 88-100% in African fls (including more than 90% of West African fls).
  More results at FactBites »

 
 

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