Expression of H‐Y Antigen on Preimplantation Mouse Embryos

Abstract
The expression of H-Y [y-linked histocompatibility] antigen on preimplantation mouse embryos was studied by complement dependent cytotoxicity. Embryos at the 8-cell stage were exposed to anti-H-Y and complement and then scored for cell death. Half of the treated embryos were killed, retarded or contained dead cells. Of those embryos which were not affected by anti-H-Y, 92% were female. In control experiments, neither normal serum plus complement nor complement alone had any specific effect on male embryos. The H-Y antigen is apparently present on preimplantation mouse embryos.