Know Your Biochemistry

We have all heard of blood groups A, B, AB and O. A good number of you actually know which group you belong to. What is the reason of this variance? The red blood cells are part of the composition of blood. This tiny cells have three different types of sugars that are the distinguishing feature between blood types. Yes. You had me right. Sugars are the reason for all this fuss. The three culprits go by the names L-fucose, N-acetyl-D-galactosamine and D-galactose. All four blood types (AB, A, B and O) have L-fucose on their surfaces. If no other sugar is attached to the red blood cells except L-fucose then they are identified as type O. Type A red blood cells have both L-fucose and N-acetyl-D-galactosamine while type B red blood cells have both L-fucose and D-galactose. Type AB have all the 3 sugars attached. Cool stuff, right? These sugars are antigenic which means they are capable of eliciting an immune response. For example, if type A blood is transfused to a patient of type B blood,...