Restriction Enzyme Polymorphisms in V_ϰ and J_ϰ Genes of Inbred and Wild Mice

Abstract

The existence of phenotypic polymorphisms in immunoglobulin heavy (H) and light (L) chain variable (V) regions suggests that somewhat different repertoires of V regions are expressed by different strains of inbred mice. Southern hybridization analyses of genomic DNA with probes specific for individual V_Ƙ groups have demonstrated that several of these polymorphisms correlate with inherited differences in V gene segments (Goldrick et al. 1985; Huppi et al. 1985; Moynet et al. 1985). Huppi et al. (1985) also observed V_Ƙ segment restriction polymorphisms by Southern hybridization that had not been suspected from studies at the protein level. Similarly, though no differences in C_Ƙ regions had been observed among inbred strains, Southern hybridization revealed a restriction polymorphism distinguishing the SJL/J strain from most others tested (Huppi et al. 1985). Use of these restriction polymorphisms and phenotypic markers in genetic experiments will help to determine the long range order of genes in the _Ƙ locus. Extension of the analyses to wild mice will give a better idea of the true extent of _Ƙ locus polymorphism and help to determine the origin of existing inbred strains.