Editing Blood type (section)

==History==
Blood types were first discovered by an Austrian physician, [[Karl Landsteiner]], working at the Pathological-Anatomical Institute of the University of Vienna (now [[Medical University of Vienna]]). In 1900, he found that blood sera from different persons would clump together (agglutinate) when mixed in test tubes, and not only that, some human blood also agglutinated with animal blood.<ref>{{cite journal |author=Landsteiner K |title=Zur Kenntnis der antifermentativen, lytischen und agglutinierenden Wirkungen des Blutserums und der Lymphe |journal=Zentralblatt für Bakteriologie, Parasitenkunde und Infektionskrankheiten|volume=27 |pages=357–362 |year=1900}}</ref> He wrote a two-sentence footnote:

{{Blockquote|The serum of healthy human beings not only agglutinates animal red cells, but also often those of human origin, from other individuals. It remains to be seen whether this appearance is related to inborn differences between individuals or it is the result of some damage of bacterial kind.<ref name=kantha>{{cite journal |last1=Kantha |first1=S.S. |title=The blood revolution initiated by the famous footnote of Karl Landsteiner's 1900 paper |journal=The Ceylon Medical Journal |date=1995 |volume=40 |issue=3 |pages=123–125 |pmid=8536328 }}</ref>}}

This was the first evidence that blood variation exists in humans. The next year, in 1901, he made a definitive observation that blood serum of an individual would agglutinate with only those of certain individuals. Based on this he classified human bloods into three groups, namely group A, group B, and group C. He defined that group A blood agglutinates with group B, but never with its own type. Similarly, group B blood agglutinates with group A. Group C blood is different in that it agglutinates with both A and B.<ref>{{Cite journal |last=Kantha |first=S. S. |date=September 1995 |title=The blood revolution initiated by the famous footnote of Karl Landsteiner's 1900 paper |url=https://pubmed.ncbi.nlm.nih.gov/8536328 |journal=The Ceylon Medical Journal |volume=40 |issue=3 |pages=123–125 |issn=0009-0875 |pmid=8536328}}</ref> This was the discovery of blood groups for which Landsteiner was awarded the Nobel Prize in Physiology or Medicine in 1930. (C was later renamed to O after the German ''Ohne'', meaning without, or zero, or null.<ref>{{Cite journal |last=Landsteiner |first=Karl |date=1961-01-02 |title=On Agglutination of Normal Human Blood |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1537-2995.1961.tb00005.x |journal=Transfusion |language=en |volume=1 |issue=1 |pages=5–8 |doi=10.1111/j.1537-2995.1961.tb00005.x |issn=0041-1132}}</ref>) Another group (later named AB) was discovered a year later by Landsteiner's students Adriano Sturli and Alfred von Decastello without designating the name (simply referring it to as "no particular type").<ref>{{Cite journal |last=Farhud |first=Dariush D. |last2=Zarif Yeganeh |first2=Marjan |date=2013 |title=A brief history of human blood groups |url=https://pubmed.ncbi.nlm.nih.gov/23514954 |journal=Iranian Journal of Public Health |volume=42 |issue=1 |pages=1–6 |issn=2251-6085 |pmc=3595629 |pmid=23514954}}</ref><ref>{{cite journal |last1=Von Decastello |first1=A. |last2=Sturli |first2=A. |title=Concerning isoagglutinins in serum of healthy and sick humans |journal=Munchener Medizinische Wochenschrift |date=1902 |volume=26 |pages=1090–1095}}</ref><ref name="Farr1979">{{cite journal |author=Farr AD |title=Blood group serology—the first four decades (1900–1939) |journal=Medical History |volume=23 |issue=2 |pages=215–26 |date=April 1979 |pmid=381816 |pmc=1082436 |doi=10.1017/s0025727300051383}}</ref> Thus, after Landsteiner, three blood types were initially recognised, namely A, B, and C.<ref name="Farr1979" />

Czech serologist [[Jan Janský]] was the first to recognise and designate four blood types in 1907 that he published in a local journal,<ref name="Janský_1907">{{cite journal |author=Janský J. |year=1907 |title=Haematologické studie u psychotiků |journal=Sborník Klinický |language=cs |volume=8 |pages=85–139}}</ref> using the Roman numerical I, II, III, and IV (corresponding to modern O, A, B, and AB respectively).<ref>{{cite journal |last1=Garratty |first1=G. |last2=Dzik |first2=W. |last3=Issitt |first3=P.D. |last4=Lublin |first4=D.M. |last5=Reid |first5=M.E. |last6=Zelinski |first6=T. |title=Terminology for blood group antigens and genes—historical origins and guidelines in the new millennium |journal=Transfusion |date=April 2000 |volume=40 |issue=4 |pages=477–489 |doi=10.1046/j.1537-2995.2000.40040477.x |pmid=10773062 }}</ref> Unknown to Janský, American physician [[William Lorenzo Moss|William L. Moss]] introduced an almost identical classification in 1910,<ref name="Moss_1910">{{cite journal|author=Moss W.L.|year=1910|title=Studies on isoagglutinins and isohemolysins|journal=Bulletin of the Johns Hopkins Hospital|volume=21|pages=63–70}}</ref> but with Moss's I and IV corresponding to Janský's IV and I.<ref name="Farr19793">{{cite journal |last1=Farr |first1=A. D. |title=Blood group serology—the first four decades (1900–1939) |journal=Medical History |date=April 1979 |volume=23 |issue=2 |pages=215–226 |doi=10.1017/S0025727300051383 |pmc=1082436 |pmid=381816 }}</ref> Thus the existence of two systems immediately created confusion and potential danger in medical practice. Moss's system was adopted in Britain, France, and the US, while Janský's was preferred in most other European countries and some parts of the US. It was reported that "The practically universal use of the Moss classification at that time was completely and purposely cast aside. Therefore in place of bringing order out of chaos, chaos was increased in the larger cities."<ref>{{cite journal |last1=Kennedy |first1=James A. |title=BLOOD GROUP CLASSIFICATIONS USED IN HOSPITALS IN THE UNITED STATES AND CANADA: FINAL REPORT |journal=Journal of the American Medical Association |date=23 February 1929 |volume=92 |issue=8 |pages=610 |doi=10.1001/jama.1929.02700340010005 }}</ref> To resolve the confusion, the [[American Association of Immunologists]], the [[American Society for Microbiology|Society of American Bacteriologists]], and the Association of Pathologists and Bacteriologists made a joint recommendation in 1921 that the Jansky classification be adopted based on priority.<ref>{{cite journal |last1=Garratty |first1=G. |last2=Dzik |first2=W. |last3=Issitt |first3=P.D. |last4=Lublin |first4=D.M. |last5=Reid |first5=M.E. |last6=Zelinski |first6=T. |title=Terminology for blood group antigens and genes—historical origins and guidelines in the new millennium |journal=Transfusion |date=April 2000 |volume=40 |issue=4 |pages=477–489 |doi=10.1046/j.1537-2995.2000.40040477.x |pmid=10773062 }}</ref> But it was not followed particularly where Moss's system had been used.<ref name="Doan1927">{{cite journal |last1=Doan |first1=Charles A. |title=The Transfusion Problem |journal=Physiological Reviews |date=1927 |volume=7 |issue=1 |pages=1–84 |doi=10.1152/physrev.1927.7.1.1 }}</ref>

In 1927, Landsteiner, who had moved to the [[Rockefeller University|Rockefeller Institute for Medical Research]] in New York, and as a member of a committee of the [[National Research Council (United States)|National Research Council]] concerned with blood grouping suggested to substitute Janský's and Moss's systems with the letters O, A, B, and AB. There was another confusion on the use of O which was introduced by Polish physician [[Ludwik Hirszfeld]] and German physician [[Emil von Dungern]] in 1910.<ref name=":0">{{cite journal |last1=Okroi |first1=Mathias |last2=McCarthy |first2=Leo J. |title=The Original Blood Group Pioneers: The Hirszfelds |journal=Transfusion Medicine Reviews |date=July 2010 |volume=24 |issue=3 |pages=244–246 |doi=10.1016/j.tmrv.2010.03.006 |pmid=20656191 }}</ref> It was never clear whether it was meant for the figure 0, German ''null'' for zero or the upper case letter O for ''ohne'', meaning without; Landsteiner chose the letter.<ref name="SchmidtOkroi2001">{{cite journal |last1=Schmidt |first1=P. |last2=Okroi |first2=M. |title=Also sprach Landsteiner – Blood Group 'O' or Blood Group 'NULL' |journal=Transfusion Medicine and Hemotherapy |date=2001 |volume=28 |issue=4 |pages=206–208 |doi=10.1159/000050239 }}</ref>

In 1928 the Permanent Commission on Biological Standardization adopted Landsteiner's proposal and stated:{{blockquote|The Commission learns with satisfaction that, on the initiative of the Health Organization of the League of Nations, the nomenclature proposed by von Dungern and Hirszfeld for the classification of blood groups has been generally accepted, and recommends that this nomenclature shall be adopted for international use as follows: 0 A B AB. To facilitate the change from the nomenclature hitherto employed the following is suggested:
* Jansky ....O(I) A(II) B(III) AB(IV)
* Moss ... O(IV) A(II) B(III) AB(I)<ref>{{Cite journal|last=Goodman|first=Neville M.|date=1940|title=Nomenclature of Blood Groups|journal=British Medical Journal|volume=1|issue=4123|pages=73|doi=10.1136/bmj.1.4123.73-a|pmc=2176232}}</ref>
}}This classification became widely accepted and after the early 1950s it was universally followed.<ref>{{Cite journal |last=Goodman |first=N. M. |date=1940-01-13 |title=Nomenclature of Blood Groups |url=https://www.bmj.com/lookup/doi/10.1136/bmj.1.4123.73-a |journal=BMJ |language=en |volume=1 |issue=4123 |pages=73–73 |doi=10.1136/bmj.1.4123.73-a |issn=0959-8138}}</ref><ref>{{cite journal |last1=Garratty |first1=G. |last2=Dzik |first2=W. |last3=Issitt |first3=P.D. |last4=Lublin |first4=D.M. |last5=Reid |first5=M.E. |last6=Zelinski |first6=T. |title=Terminology for blood group antigens and genes—historical origins and guidelines in the new millennium |journal=Transfusion |date=April 2000 |volume=40 |issue=4 |pages=477–489 |doi=10.1046/j.1537-2995.2000.40040477.x |pmid=10773062 }}</ref>

Hirszfeld and Dungern discovered the inheritance of blood types as [[Mendelian genetics]] in 1910 and the existence of sub-types of A in 1911.<ref name=":0" /><ref>{{cite journal |last1=Dungern |first1=E. |last2=Hirschfeld |first2=L. |title=Über Vererbung gruppenspezifischer Strukturen des Blutes |journal=Zeitschrift für Induktive Abstammungs- und Vererbungslehre |date=December 1911 |volume=5 |issue=1 |pages=196–197 |doi=10.1007/BF01798027 }}</ref> In 1927, Landsteiner, with [[Philip Levine (physician)|Philip Levine]], discovered the [[MN blood group|MN blood group system]],<ref>{{cite journal |last1=Landsteiner |first1=K. |last2=Levine |first2=P. |title=A New Agglutinable Factor Differentiating Individual Human Bloods. |journal=Experimental Biology and Medicine |date=1927 |volume=24 |issue=6 |pages=600–602 |doi=10.3181/00379727-24-3483 }}</ref> and the [[P antigen system|P system]].<ref>{{cite journal |last1=Landsteiner |first1=K. |last2=Levine |first2=P. |title=Further Observations on Individual Differences of Human Blood. |journal=Experimental Biology and Medicine |date=1927 |volume=24 |issue=9 |pages=941–942 |doi=10.3181/00379727-24-3649 }}</ref> Development of the [[Coombs test]] in 1945,<ref>{{cite journal |vauthors=Coombs RR, Mourant AE, Race RR |title=A new test for the detection of weak and incomplete Rh agglutinins |journal=Br J Exp Pathol |volume=26 |pages=255–66 |year=1945 |issue=4 |pmid=21006651 |pmc=2065689 }}</ref> the advent of [[transfusion medicine]], and the understanding of [[ABO hemolytic disease of the newborn]] led to discovery of more blood groups. {{as of|2024|October}}, the International Society of Blood Transfusion (ISBT) recognizes 47 blood groups.<ref name=":1" />