GENETIC-MAPPING OF CMV1 IN THE REGION OF MOUSE CHROMOSOME-6 ENCODING THE NK GENE COMPLEX-ASSOCIATED LOCI LY49 AND MUSNKR-P1

The Cmv1 resistance gene controls splenic replication of murine cytome galovirus (MCMV) and confers natural killer (MZ) cell-mediated resista nce to otherwise lethal infection. The Cmv1 phenotypes of 13 inbred mo use strains have been assessed, and it was found that the Cmv1(r) resi stance phenotype was restricted to the C57BL/6J and Ma/MyJ strains. We have further analyzed the linkage of Cmv1 to the NK gene complex (NKC ) mapping to distal mouse chromosome 6 in 99 (BALB/c x C57BL/6J)F-1 x BALB/c backcross mice using cloned gene probes and microsatellite mark ers from this region. No recombinants were observed between Cmv1 and t he NRC-associated Ly49 and musNKR-P1 multigene families, nor the Kap l ocus, nor with 7 microsatellite markers, indicating that Cmv1 is close ly linked (<1 cM) to all of these markers. Analysis of the genotype of the MCMV-susceptible BXD8 RI strain around the NKC region revealed th at it had C57BL/6J alleles at microsatellite markers immediately proxi mal and distal to Cmv1. This suggests that the Cmv1(s) phenotype of th is strain is due to a germ-line mutation. Thus, the close linkage of C mv1 to the Ly49 and musNKR-P1 multigene families suggests that it may represent an NK cell recognition structure encoded in the NKC region. (C) 1995 Academic Press, Inc.