Discovery of the blood groups In 1900 Karl Landsteiner found out that the blood of two people under contact agglutinates, and in 1901 he found that this effect was due to contact of blood with blood serum. As a result, he succeeded in identifying the three blood groups A, B and O, which he labelled C, of human blood.Click to see full answer. Also asked, what did Karl Landsteiner discover and what impact did it have on society?Karl Landsteiner discovered human blood groups in 1900 and laid the foundation for the modern medical practice of blood transfusion. The ABO blood groups have a role in physiology beyond their importance for blood transfusion.Also Know, what important discovery did Karl Landsteiner make? Karl Landsteiner, (born June 14, 1868, Vienna, Austrian Empire [Austria]—died June 26, 1943, New York, N.Y., U.S.), Austrian American immunologist and pathologist who received the 1930 Nobel Prize for Physiology or Medicine for his discovery of the major blood groups and the development of the ABO system of blood People also ask, how did they discover blood types? Landsteiner discovered the ABO blood group system by mixing the red cells and serum of each of his staff. In 1930, Landsteiner received the Nobel Prize in physiology and medicine for his work (1). The gene that determines human ABO blood type is located on chromosome 9 (9q34. 1) and is called ABO glycosyltransferase.What was Karl Landsteiner’s contribution to the field of forensic serology?For his discovery of blood groups, Landsteiner received the 1930 Nobel Prize in Physiology or Medicine. Landsteiner’s account of blood types brought a new tool to forensic science. For the first time, forensic scientists could definitively compare blood evidence left at a crime scene to the blood of a suspect.