Blood group: Difference between revisions
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Blood groups are determined by the [[ | Blood groups are determined by the [[Carbohydrates|carbohydrates]] attached to the proteins in the [[Glycocalyx|glycocalyx]] on the surface of the [[Red blood cells|red blood cells]]. Different [[Oligosaccharide|oligosaccharide]] structure for each: | ||
*Same basic oligosaccharide for blood group O | *Same basic oligosaccharide for blood group O | ||
*A & B have extra, but different, terminal sugar | *A & B have extra, but different, terminal sugar | ||
*N-acetyl-galactosamine for A, galactose for B | *N-acetyl-galactosamine for A, galactose for B | ||
A sugar added by specific [[ | A sugar added by specific [[Glycosyltransferase|glycosyltransferase]] (GT) enzymes and the pattern is determined by which glycosyltransferase gene we carry. | ||
There are two GT enzymes present (GTA and GTB) which are encoded for by different forms of the same [[ | There are two GT enzymes present (GTA and GTB) which are encoded for by different forms of the same [[Genes|gene]]. Blood group A produce GTA that put [[N-acetly-galctosamine|N-acetly-galctosamine]] on the surface of the red blood cells and blood group B produce GTB that put on [[Galactose|galactose]] on the surface of the red blood cells <ref>David Goodsell &amp;amp; RCSB Protein Data Bank, 2015, Website, assessed at 03/12/2015, avaliable from: fckLRhttp://www.rcsb.org/pdb/101/motm.do?momID=156</ref>. | ||
In O blood group the GT is non-functional. AB blood group produces both GTA and GTB. | In O blood group the GT is non-functional. AB blood group produces both GTA and GTB. | ||
[[Oligosaccharide|Oligosaccharide]] structure of blood group O consists of 2 galactose molecules, 1 [[ | [[Oligosaccharide|Oligosaccharide]] structure of blood group O consists of 2 galactose molecules, 1 [[Fructose-1,6-bisphosphate|fructose]] molecule and 1 N- acetyl glucoanime. | ||
=== '''<u></u>''' | === Rhesus Blood Group === | ||
<br>Annotated as the Rh system, this involves grouping individuals by the presence or absence of the D antigen of the Rh blood group system. The D antigen is the most immunogenic of the Rh antigens. Patients are referred to as Rh+ or Rh- (positive or negative), according to whether or not they possess the D antigen. Rh+ individuals may only donate blood to other positive individuals. Rh- individuals may donate to both positive and negative recipients<ref>Talaro, Kathleen P. (2005). Foundations in microbiology (5th ed.). New York: McGraw-Hill. pp. 510–1. ISBN 0-07-111203-0.</ref>. | |||
=== '''<u></u>'''References === | |||
<references /><br> | <references /><br> | ||
Revision as of 14:19, 24 October 2017
Blood groups are determined by the carbohydrates attached to the proteins in the glycocalyx on the surface of the red blood cells. Different oligosaccharide structure for each:
- Same basic oligosaccharide for blood group O
- A & B have extra, but different, terminal sugar
- N-acetyl-galactosamine for A, galactose for B
A sugar added by specific glycosyltransferase (GT) enzymes and the pattern is determined by which glycosyltransferase gene we carry.
There are two GT enzymes present (GTA and GTB) which are encoded for by different forms of the same gene. Blood group A produce GTA that put N-acetly-galctosamine on the surface of the red blood cells and blood group B produce GTB that put on galactose on the surface of the red blood cells [1].
In O blood group the GT is non-functional. AB blood group produces both GTA and GTB.
Oligosaccharide structure of blood group O consists of 2 galactose molecules, 1 fructose molecule and 1 N- acetyl glucoanime.
Rhesus Blood Group
Annotated as the Rh system, this involves grouping individuals by the presence or absence of the D antigen of the Rh blood group system. The D antigen is the most immunogenic of the Rh antigens. Patients are referred to as Rh+ or Rh- (positive or negative), according to whether or not they possess the D antigen. Rh+ individuals may only donate blood to other positive individuals. Rh- individuals may donate to both positive and negative recipients[2].