Association between histocompatibility type and the ability to make anti‐Rh antibodies

The HL‐A types of Rh‐negative women with and without anti‐Rh antibodies were examined. In those who made Rh antibodies, there was an excess of HL‐A1, and a deficiency of HL‐A2 and W10, approaching the conventional level of significance. There was, however, a highly significant lack, in the antibody‐making group, of subjects with only one antigen detected at the first (LA) locus. The capacity to make anti‐Rh antibodies and that to make cytotoxic anti‐HL‐A antibodies were strongly correlated.