Genetic and molecular mapping of the Hmt region of mouse.

We have mapped a new region of the mouse major histocompatibility complex (MHC) that contains the nuclear gene, Hmt, for the maternally transmitted antigen, Mta. The Hmt region of chromosome 17 lies between a recombinational breakpoint distal to Tla and another proximal to Tpx‐1, thus including Pgk‐2. A novel MHC class I gene fragment, R4B2, was cloned and mapped to this region as was another new class I gene, Thy19.4. Both lie proximal to Pgk‐2, within the distal inversion in t‐haplotypes. The presence of several other MHC class I genes in the Hmt region is predicted from analysis of the recombinants that define the region.