Emm. A red cell antigen of very high frequency.

Anti-Emm, an antibody to a public red cell antigen, was found in the serums of four Emm-propositi and in the serum of the Emm-brother of one of them. Three of the propositi were men, and their antibodies, as well as that of the compatible brother, were believed to be "naturally occurring." Since there are two Emm-siblings in one family, Emm is probably an inherited characteristic.