Use of flow-sorted canine chromosomes in the assignment of canine linkage,radiation hybrid, and syntenic groups to chromosomes: Refinement and verification of the comparative chromosome map for dog and human

The mapping of the canine genome has recently been accelerated by the avail ability of chromosome-specific reagents and publication of radiation hybrid (RH), genetic linkage, and dog/human comparative maps, but the assignment of mapping groups to chromosomes is incomplete. To assign published radiati on hybrid, linkage, and "syntenic" groups to chromosomes, individual marker s found within each group have been amplified from canine and vulpine flow- sorted, chromosome-specific DNAs as templates. Here a further 102 type I ge netic markers (previously mapped in human) and 21 further type LT markers a re assigned to canine chromosomes using marker-specific PCR. We have assign ed all linkage, HH, and syntenic groups in the two most recently published canine genome maps to chromosomes. This demonstrates directly that there is at least one published mapping group for each of the 38 canine autosomes a nd thus that the coverage of the canine chromosome map is approaching compl etion. The dog/human comparative map is one of the most complex so far desc ribed, with 90 separate segments of chromosomal homology previously seen in dog-on-human cross-species chromosome-painting studies. The total of 142 t ype I markers now placed on canine chromosomes using this method of marker mapping has allowed us to confirm the placement of the great majority (83) of the 90 homologous segments. The positions of the remaining homologous se gments were confirmed in new cross-species chromosome-painting experiments (dog-on-human, fox-on-human). (C) 2000 Academic Press.