Refined genetic and comparative physical mapping of the canine copper toxicosis locus

Recently, the copper toxicosis (CT) locus in Bedlington terriers was assign ed to canine chromosome region CFA10q26, which is homologous to human chrom osome region HSA2p13-21. A comparative map between CFA10q21-26 and HSA2p13- 21 was constructed by using genes already localized to HSA2p13-21. A high-r esolution radiation map of CFA10q21-26 was constructed to facilitate positi onal cloning of the CT gene. For this map, seven Type I and eleven Type II markers were mapped. Using homozygosity mapping, the CT locus could be conf ined to a 42.3 cR(3000) region, between the FH2523 and C10.602 markers. On the basis of a partial BAC contig, it was estimated that 1-cR(3000) is equi valent to approximately 210 kb, implying that the CT candidate region is th erefore estimated to be about 9 Mb.