A NEW GENE-MAPPING RESOURCE - INTERSPECIES HYBRIDS BETWEEN PERE-DAVIDS DEER (ELAPHURUS-DAVIDIANUS) AND RED DEER (CERVUS-ELAPHUS)

Three male Fl hybrids between Pere David's deer and red deer were mate d to red deer to produce 143 backcross calves. The pedigrees are a rar e example of a fertile hybrid between evolutionarily divergent species . We examined the use of these families for genetic mapping of evoluti onarily conserved (Type I) loci by testing for genetic linkage between five species-specific protein variants and 12 conserved DNA probes. T wo probes were homologous, and the remainder syntenic, to the protein coding loci in cattle or humans. Using six restriction enzymes, each D NA probe detected one or more restriction fragments specific to Pere D avid's deer. Linkage analyses among the species-specific variants plac ed the loci into four linkage groups within which linkage between adja cent loci and gene order was supported by a LOD > 3. The linkage group s were (HPX, HBB)-FSHB-ACP2, LDHA-CD5-IGF2, BMP3-(GC, ALB)-(KIT, PDGFR A) and LDLR-C3-FGF1. Southern and protein analysis of LDHA and ALB pro vided identical segregation data. These linkage groups were consistent with the cattle gene map and provide new information for comparing th e gene maps of ruminants, humans and mice. The deer hybrids are an imp ortant new resource that can contribute to the comparative analysis of the mammalian genome.