PROBLEM: To explore the nature of the genes in the grc.
METHOD: Chromosome walking of the grc and sequencing new genes.
RESULTS: The RT1.O, N genes have been aligned, and two new types of genes, RT1.S1,2 and Rpr1,2,3, have been discovered and mapped. An extensive physical map of the grc region is presented.
CONCLUSION: The disease associations in both the rat and the human appear to cluster in two regions that map in approximately the same place in both species, given the translocation that occurred in the major histocompatibility complex (MHC) of the rat relative to the MHC of the human.