BLOOD-GROUPS AND RACE— MILLOT 5Q5 



red corpuscles either singly {A or B) or together {AB), or not at all 

 (0); certain individuals therefore have only A, and others have B, 

 and others both agglutinogens; while yet others are totally devoid of 

 either. It is this which is described somewhat inaccurately (but 

 which has found its way into scientific parlance) as the existence in 

 the human species of four blood-groups — group A, group B, group AB, 

 and group 0, this last containing neither A nor B. 



To the agglutinogens of the corpuscles correspond agglutinins in 

 the serum which are distinguished by the Greek letters a (or anti-^) 

 and /3 (or &nti-B). The same blood never possesses agglutinins active 

 in the presence of their opposites; or in other words, the serum of a 

 given individual never agglutinates its own corpuscles — a result which 

 in fact would make circulation, and consequently life, impossible. 

 Accordingly the serum of bloods belonging to group A contains, not 

 agglutinin a which agglutinates A, bul agglutinin /3; and it is the serum 

 of group B which contains agglutinin a. The group AB, possessor 

 of two agglutinogens, can never have agglutinins, whilst group 

 possesses at the same time both a and /3. From this it follows that 

 the complete formulas of the blood-groups are A^, Ba, ABO, Oa^. 

 This nomenclature is the one usually adopted, but two others, those 

 of Jansky and Moss, are also in use.^ 



If one brings together the blood of two people belonging to the same 

 group there is no result — the blood mixes normally. If on the other 

 hand one brings together blood samples from groups A and B, a will 

 react with A, /3 with B, and agglutination will ensue.* 



In the light of these facts we now know how to practice transfusion 

 without risk of accident; it is enough to estabhsh to which group the 

 patient belongs, and to obtain the blood from a donor belonging to the 

 same group as himself. Nothing is easier, for in the big towns there 

 have come into existence speciaUzed institutes whence, by telephoning, 

 one can immediately obtain a "donor" of the reqiured type. In actual 

 fact, the agglutinins are only active when concentrated, and those of 

 the donor, diluted in the blood of the receiver, appear practically with- 

 out effect; it results that one can always transfuse blood of group 

 (universal donor) into a wounded patient, whatever his group, without 

 serious results; and that, conversely, a subject of group AB can receive 

 without harm any blood whatever (universal receiver). 



Human beings, therefore, are divided into four groups, according 

 to the serological properties of their blood. These preliminary 

 explanations having been given, let us see what main characteristics 

 are revealed by the reactions of agglutination; after which we will 



» The groups are indicated by Roman figures; according to Jansky 0=7, A=II, B=III, AB=IV; according 

 to Moss AB=I, A=II, B=III, 0=IV. 



* The hypothesis of agglutinins and agglutinogens is a convenient explanation of the facts; but does it 

 correspond with reality? Are there definite chemical bodies involved? No doubt we have to reckon only 

 with special properties which may be common to many different substances, under certain well-defined 

 physical conditions (Mendes— Correa). 



31508—38 36 



