Biochemical comparison of major histocompatibility complex molecules from different subspecies of Mus musculus: evidence for trans-specific evolution of alleles.

Abstract

H-2 haplotypes were extracted from wild mice of 3 subspecies, M. m. domesticus, M. m. molossinus and M. m. castaneus, that were separated from one another for some 1-2 million yr. Serologically indistinguishable molecules controlled by some of the polymorphic H-2 loci were compared by tryptic peptide mapping, and the maps were found to be identical. A number of instances of biochemically indistinguishable H-2 [major histocompatibility complex] molecules were found among wild rice and inbred strains of the M. m. domesticus subspecies. Some of the H-2 alleles have not altered fo for > 1 million yr. This apparent stability of H-2 genes with their extraordinary polymorphism (some 100 alleles at each of the polymorphic H-2 loci), may mean that the H-2 alleles evolve as if they were separate loci.