Embryonal carcinoma antigen and the T/t locus of the mouse.

Abstract
The presence of the [embryonal carcinoma mouse teratoma cell] F9 antigen and 4 other antigens related to the T/t locus of the mouse was investigated by immunofluorescence on implantation embryos. In morulae heterozygous for any of these t haplotypes, both the appropriate t antigen and the F9 antigen are expressed. The F9 embryos homozygous for some (tw32 and tw5) but not for other haplotypes. Whatever the time of action of a t haplotype, its corresponding antigen is apparently expressed during cleavage and the F9 antigen is apparently specified by a gene(s) in the region of the T/t locus.