Respuesta :
The Rhesus factor is clinically the most important protein-based blood group. The presence of rhesus protein on blood represents as an antigen which indicates if the blood is positive or negative. Rhesus factor was discovered in 1940 by K. Landsteiner and A. S. Wiener. Hope this answer helps.
Positive Rh factor represents the presence of the rhesus protein on the blood cells. Rh factor or Rhesus factor is used to describe the presence of antigen Rh (D) in the blood. A person who is, for example, AB Positive (AB+) has the A and B antigens and the Rh(D) antigen, whereas someone who is AB Negative (ab-) lacks the Rh(D) antigen. Antibodies to Rh antigens can be involved in hemolytic transfusion reactions and they increase the risk of Hemolytic disease of the fetus and newborn, so it is important for mother and the baby to have the same Rh factor.