Intra‐H‐2 Recombination in H‐2^b/H‐2^t1 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 parental 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 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 halotype designations H-218, H-2i9 and H2at1.