How were the blood types found？ What is blood type Rh？

In 1900， Dr. Lanz Tanner of University of Vienna's Institute of Pathology found that some patients could survive after the transfusion， and some would die. Through experiments and research， he found that there were three blood types， while agglutination caused by interblending of red blood cells and blood serum of different blood types was the real cause of transfusion reaction. Later， more doctors continued to conduct experiments， and finally a more complete human blood-group system was formed.

Blood type Rh is one of the currently known 30 human blood group systems， its clinical importance is second only to ABO blood group system， and it is also a very complex human blood group system. In simple terms， it is called that people of Rh antigen on the surface of red blood cells have Rh-positive blood type， otherwise， they have Rh-negative blood type. D antigen is the most important in Rh antigen family， therefore， Rh positive is also known as D positive， and Rh antibody can also be referred to as anti-d antibody. Rh-negative blood type accounts for 15%～17% in Caucasians （i.e.， the white race）， 3%～5% in African-Americans， and less than 0.1% in Asians. Chinese of Rh-negative blood type accounts for 0.3%～0.4%.