MAPPING THE FLV LOCUS CONTROLLING RESISTANCE TO FLAVIVIRUSES ON MOUSECHROMOSOME-5

Genetically determined resistance to flaviviruses in mice is a dominan t trait conferred by alleles at a single autosomal locus designated Fl v, but no gene products have been associated with this locus and the m echanism of resistance is not well understood. To further characterize this model of genetic resistance, we conducted mapping studies to det ermine the chromosomal location of Flv. Because of evidence suggesting that the Flv locus is on chromosome 5, three-point backcross linkage analyses were used to define the location of Flv relative to previousl y assigned chromosome 5 markers. The results confirm the chromosome 5 location of Flv and indicate a map position between the anchor loci rd and Gus-s. The chromosomal localization of Flv is the first step in t he production of a detailed linkage map of the Flv region, which may o pen approaches to positional cloning of the resistance gene.