Genetic Organization of the Qa and Tla Regions: Gene Mapping Based on the Analysis of Recombinant Strains

Abstract

Studies on the genetic organization of the mouse major histocompatibility complex (MHC) have been highly dependent on the development of intra-MHC recombinant inbred strains of mice (Klein 1979). For example, well over 200 recombinant strains have been developed for mapping the loci of the classically defined H—2 complex (summarized in Klein et al., 1983, and in Mouse Newsletter volumes 68, 70 and 74). Unfortunately however, only a handful of recombinant strains exist which carry crossover points associated with the Qa or Tla regions (Flaherty, 1981; O’Neill, 1986). In the past five years, the genetic analysis of the mouse MHC, has been highlighted by substantial advances in the molecular characterization and cloning of MHC genes including those of the Qa and Tla regions (Steinmetz et al., 1982; Weiss et al., 1985; Fisher et al., 1985). This development, rather than detracting from the value of traditional analysis with intra-MHC recombinant strains, provides an opportunity to combine new and traditional approaches into a more powerful battery of tools for the examination of the organization, function and evolution of the class I genes of the Qa and Tla regions. Moreover, the advent of molecular genetics has even created new uses for intra-MHC recombinant strains including the study of the molecular character and distribution of meiotic recombination sites (Steinmetz et al., 1986; Kobori et al., 1986).