Studies on the genetic and antigenic basis of tumour transplantation Linkage between a histocompatibility gene and 'fused' in mice

Abstract Inoculation of mice from appropriate crosses with two strain A tumours and one dba (sub­line 2) tumour showed close linkage of such a gene with the locus for ‘fused’. With the A strain it was shown that the gene was identical with that for antigen II present in the erythrocytes. The gene is therefore labelled H2. Of sixty-nine backcross mice tested, both serologically and by tumour inoculation, sixty-five gave concordant results, four discordant results. In general, it appears that serological tests are preferable to tumour inoculation in the identification of genotypes. On serological grounds it is suggested that the dba gene is an allele of the above and should be called Hd2. It is possible that there is a long series of alleles at this locus. The indicated genotype of the strains used is as follows: A, H2H2; dba, H d2H d2; CBA, C57 and P, h2h2; CA, Fuh2/fu h2. Further tests may show differences in the h2 allele in the last four strains. It is uncertain whether any cross-overs occurred in 257 backcross mice tested.