Apparent violation of "Landsteiner's law".

A healthy Caucasian woman who possessed blood groups A1H(O) on her red cells as well as in her saliva and serum had no anti blood-group B “complete” or “incomplete” agglutinins nor hemolysins as determined either on whole serum or its concentrated beta-gamma globulin fraction. No anti-B antibody was stimulated by immunization with highly active human blood group B glycoprotein. No blood group B antigenic determinants were demonstrable on the proposita's red cells or in her saliva by any of numerous serological and enzymatic methods at various red cell concentrations between 2°C and 37°C, nor by the highly sensitive immunoglobulin-latex test. Immunization with the proposita's red cells did not elicit anti-blood group B antibodies in chickens and rabbits. Blood groups A and O but not B occurred in members of this woman's family which was studied through 3 generations.