HIGH-RESOLUTION MAPPING AND RECOMBINATION INTERVAL-ANALYSIS OF MOUSE-CHROMOSOME-17

Analysis of homologous recombination in eukaryotes has shown that some meiotic crossing-over occurs preferentially at specific genomic sites of limited physical distance called recombinational hotspots. In the mouse, recombinational hotspots have only been defined in the major hi stocompatibility complex (MHC) on chromosome (Chr) 17. In an attempt t o examine whether hotspots are unique to the MHC or are present throug hout the genome, high-resolution linkage maps of Chr 17 based on five backcrosses involving different inbred strains have been generated. Th ese maps separate many markers that were previously shown at the same map position and allow a detailed analysis of recombination patterns a cross Chr 17. Corresponding recombination intervals in these maps have been compared for the identification of intervals with very little or no recombination in certain genetic crosses and considerable recombin ation in other genetic crosses. This approach has been termed Recombin ation Interval Analysis. Possible haplotype-dependent non-MHC hotspots , as well as previously identified MHC hotspots, have been detected by interval analysis.