[Numeric terminology of erythrocyte blood group antigens]

Since the discovery of the first human blood groups, the terminology for erythrocyte blood group antigens has evolved and become inconsistent. In some cases, a single letter is used (eg, A/B, E/e), in some others a symbol with a superscript to denote allelic products is used (eg, Fya/Fyb, Jka/Jkb) while in still others, a numerical notation is used (eg, Fy3, Lu4, K11). Even within the same blood group system, antigens have been named by different terminology (eg, K/k, Kpa/Kpb, K11/K17) and the same antigen was given different names in different laboratories. Therefore a necessary alternative 'popular' terminology was suggested by the ISBT (International Society of Blood Transfusion) Working Party; In its last monograph, published in 1995 and reviewed in 1996, erythrocyte blood group antigens are classified into 23 systems, 5 collections and 2 series. The Working Party also suggested guidelines for establishing new blood group systems and including new specificities into the nomenclature.