RH- Blood: Another Human Mystery


     Alot of the information found below may be confusing so we did our best to elaborate as best we could on complicated terminologies and definitions. We also pride ourselves in this website's credibility so we made our best attempt to not mix fact and fiction. Our research is never ending and eventually we will return to this article along with all the others to continue contributing our findings. We hope you enjoy this article and can't wait to see your thoughts expressed in the comments below. Thank you!

Rhesus Blood Group Factor

     In 1937, Karl Landsteiner & Alexander Weiner discovered the Rhesus (RH) factor in blood after observing an antigenic reaction in the serum component of rabbit blood caused by the blood of the Rhesus monkey which was injected into that of the rabbits. The RH group type is the second most important group type used to identify blood, with the ABO system coming first in significance.

     The ABO blood group system describes the presence of A and B (one, both or neither) antigens in red blood cells (RBC). Antigens expressed in the ABO group are sugars that are attached to various parts within the RBC membrane. The RH blood group system denotes proteins on the surface of the RBCs and are used to transport carbon dioxide between the plasma membrane which is found in all cells and used to separate the interior of a cell from the outside environment.

     An approximate estimate reveals that in the United States that only 15% of the United States Population (331.42 million as of 2021) has RH- blood while the other 85% are positive. World wide, the rarest blood types are as follows (as of 2018):

    1.) AB Negative - 0.6%
    2.) B Negative - 1.5%
    3.) AB Positive - 3.4%
    4.) A Negative - 6.3%
    5.) O Negative - 6.6%
    6.) B Positive - 8.5%
    7.) A Positive - 35.7%
    8.) O Positive - 37.4%

A Rhesus monkey

Rhesus Disease

     Rhesus group types are solely identified on whether or not they have the D antigen present on the RBCs. If a blood group type is identified as having the D antigen (RHD) then the blood type would be a positive (Ex. O Positive blood). If there is no D antigen present than the blood type is a negative (Ex. O negative). The D antigen exists to prevent Rhesus D Haemolytic Disease. This is when the body of the RH- mother treats her RH+ baby as a parasite and generates antibodies to attack the RBCs of the child, effectively killing it. In order to prevent this doctors will give the mother a medication called RHo(D) Immune Globulin which is an immunizing agent. RH- mothers and RH- patients who receive RH+ blood transfusions need this. Another interesting thing to note is that when it comes to blood transfusions, Rh+ individuals cannot receive Rh- blood however individuals with Rh- blood can receive Rh+ blood.

Blood type compatibility chart

Evolutionary Connection

     There is none. At least not that we know of, if there even is one. The Rhesus monkey in which the Rhesus factor was discovered had the same antigens previously discussed and it has a certain gene that is not found in humans with Rh- blood. There is no explanation for why this is or is there any evolutionary connection that can be made regarding it. This among the other several strange things stated here is where the theory of alien hybrids comes from.


Medicine Plus  –  Blood Rarity I  –  Blood Rarity II  –  Blood Rarity III  –  The Conversation  –  Evolutionary Genetics  –  Microbiology Information