Intra-H-2 recombination in H-2b/H-2t1 heterozygotes in the mouse I. Four cases of crossing over between the S And D regions.

An examination of 1009 backcross animals produced from H-2b/H-2t1 heterozygotes resulted in the detection of four cases of intra-H-2 recombination. Three of the recombinants received the K region from H-2b and the D region from the H-2t1 parenteral chromosome. The fourth recombinant received a K region from the H-2t1 parental chromosome and the D region from H-2b. Ss typing revealed that crossing over occurred between the S and D regions of the H-2 complex in all four cases. Three of the four recombinants were developed into inbred strains and assigned the haplotype designations H-2i8, H-2i9 and H-2at1.