V, A "NEW" Rh ANTIGEN, COMMON IN NEGROES, RARE IN WHITE PEOPLE Albert DeNatale, Ph.C. Amos Cahan, M.D. James A. Jack, M.S., New York Robert R. Race, Ph.D. and Ruth Sanger, Ph.D., London, England A "new" blood group antibody has been found in the serum of a white, adult patient (Mr. V), in St. Luke's Hospital, who suffered from an obscure anemia and received 26 transfusions between March 18 and Sept. 15, 1954. The antibody was first discovered at St. Luke's Hospital when the cross match for the 27th transfusion was incompatible; subsequent inquiry showed that this prospective donor was a Negro, as were six of the previous donors. The red blood cell antigen identified by this antibody at first appeared to be confined to Negroes but it has now disclosed itself as being present rarely in whites, frequently in New York Negroes, and still more frequently in West Africans.