An integrated cytogenetic, radiation-hybrid, and comparative map of dog Chromosome 5

The development of a detailed genome map For the domestic dog (Canis famili aris, CFA) is a prerequisite for the continued use of this species as a mod el system for the study of inherited traits. We present an integrated cytog enetic, radiation-hybrid, and comparative map of dog Chromosome (Chr) 5 (CF A 5). The map comprises 14 gene markers, selected from loci previously mapp ed within the corresponding evolutionarily conserved chromosome segments (E CCS) of the human genome. Large-insert clones representing each marker were first isolated and mapped by fluorescence in situ hybridization (FISH) ana lysis to determine their subchromosomal localization on CFA 5. Thirteen gen e markers were subsequently mapped by using a commercially available whole genome radiation hybrid (WC-RH) panel for the dog. Nine anonymous markers M ere also assigned to CFA 5 by both FISH and WG-RH analysis. The 22 markers formed six RH-linkage groups, spanning each of the four ECCS comprising th is 99 megabase chromosome. All cytogenetic, WC-RI-I, and comparative mappin g data were in agreement and were combined to determine both the most likel y locus order within each linkage group, and also the gross relative orient ation of the corresponding ECCS. This study provides a resource for the tra nsfer of information from the human transcript map to that of the dog, and extends existing data regarding the structural relationships between CFA 5 and its evolutionary counterparts within the human genome.