ABO blood group system in blood type distribution within human subpopulations. In the UK, the distribution of blood type frequencies through the population still shows some correlation to the distribution of placenames and to the successive invasions and migrations including Norsemen, Danes, Saxons, Celts, and Normans who contributed the morphemes to the placenames and the genes to the population. The two common O alleles, O01 and O02, share their first 261 nucleotides with the group A allele A01. However, unlike the group A allele, a guanosine base is subsequently deleted. A premature stop codon results from this frame-shift mutation. This variant is found worldwide,
ABO blood group system group B blood agglutinates with group A. Group C blood is different in that it agglutinates with both A and B. This was the discovery of blood groups for which Landsteiner was awarded the Nobel Prize in Physiology or Medicine in 1930. In his paper, he called the specific blood group interactions as isoagglutination, and also introduced the concept of agglutinins (antibodies), which is the actual basis of antigen-antibody reaction in ABO system. He asserted: Thus, he discovered two antigens (agglutinogens A and B) and two antibodies (agglutinins - anti-A and anti-B). His third group (C) indicated absence of both