how does the blood group rhNULL form
Answers
Answer:
thai will ocuur in pregnancy time I think when a o b +give blood combine
Answer:
The rarest blood type in existence is Rhnull blood. This stuff is characterized by a complete lack of antigens in the Rh system, which is the largest blood group system. This includes the D antigen (Rh factor, baby), plus the other 50-something antigens in the group.
Explanation:
The Rh blood group system is a human blood group system. It is the second most important blood group system, after the ABO blood group system. The Rh blood group system consists of 49 defined blood group antigens,[1] among which the five antigens D, C, c, E, and e are the most important. There is no d antigen. Rh(D) status of an individual is normally described with a positive or negative suffix after the ABO type (e.g., someone who is A Positive has the A antigen and the Rh(D) antigen, whereas someone who is A Negative lacks the Rh(D) antigen). The terms Rh factor, Rh positive, and Rh negative refer to the Rh(D) antigen only. Antibodies to Rh antigens can be involved in hemolytic transfusion reactions and antibodies to the Rh(D) and Rh(c) antigens confer significant risk of hemolytic disease of the fetus and newborn.
The term "Rh" was originally an abbreviation of "Rhesus factor." It was discovered in 1937 by Karl Landsteiner and Alexander S. Wiener, who, at the time, believed it to be a similar antigen found in rhesus macaque red blood cells. It was subsequently learned the human factor is not identical to the rhesus monkey factor, but by then, "Rhesus Group" and like terms were already in widespread, worldwide use. Thus, notwithstanding it is a misnomer, the term survives (e.g., rhesus blood group system and the obsolete terms rhesus factor, rhesus positive, and rhesus negative – all three of which actually refer specifically and only to the Rh D factor and are thus misleading when unmodified). Contemporary practice is to use "Rh" as a term of art instead of "Rhesus" (e.g., "Rh Group," "Rh factors," "Rh D," etc.).
The significance of their discovery was not immediately apparent and was only realized in 1940, after subsequent findings by Philip Levine and Rufus Stetson.[2] The serum that led to the discovery was produced by immunizing rabbits with red blood cells from a rhesus macaque. The antigen that induced this immunization was designated by them as Rh factor to indicate that rhesus blood had been used for the production of the serum.[3]
In 1939, Phillip Levine and Rufus Stetson published in a first case report the clinical consequences of non-recognized Rh factor, hemolytic transfusion reaction, and hemolytic disease of the newborn in its most severe form.[4] It was recognized that the serum of the reported woman agglutinated with red blood cells of about 80% of the people although the then known blood groups, in particular ABO were matched. No name was given to this agglutinin when described. In 1940, Karl Landsteiner and Alexander S. Wiener made the connection to their earlier discovery, reporting a serum that also reacted with about 85% of different human red blood cells.[5]
In 1941, Group O: a patient of Dr. Paul in Irvington, NJ, delivered a normal infant in 1931:[6] this pregnancy was followed by a long period of sterility. The second pregnancy (April, 1941) resulted in an infant suffering icterus gravis.[7] In May 1941, the third anti-Rh serum (M.S.) of Group O became available.[8]