The mapping panel used is composed of 19 three-generation pedigrees, summarized in the table below. For all but one family, DNA was available from all four grandparents, both parents and multiple offspring. The panel contains 247 individuals, including 183 F2 offspring. The average number of offspring per family is 9.6.
The majority of animals (218 animals, 163 F2 progeny) are from the Cornell Canine Reference Families (CCRF). The ancestral strains from which these pedigrees derive include purebred miniature and toy poodles, Norwegian elkhounds, Irish setters and several genetically distinct strains of laboratory beagles. The grandparents of these pedigrees represented distinct crosses derived from the various ancestral strains. Pedigrees from the James A. Baker Institute for Animal Health were developed as part of a research resource 'Models of Hereditary Retinal Degeneration'.
DNA was prepared from all reference pedigrees using modifications of standard protocols (Bell et al., 1981). All DNA samples used in the above studies were supplied from dogs that had been housed under protocols approved by the Institutional Animal Care and Use Committees of Cornell University and The Fred Hutchinson Cancer Research Center
| Pedigree | Number of F2s | Ancestry of founders |
|---|---|---|
| 1 (CF-4) | 16 | a,b |
| 2 (CF-5a) | 6 | f,h |
| 3 (CF-5b) | 9 | a,f |
| 4 | 5 | a,b |
| 5 | 3 | a,b |
| 6 | 13 | a,c |
| 7 | 6 | a,d |
| 8 | 5 | a,d |
| 9 | 6 | a,b |
| 10 | 14 | a,e |
| 11 | 9 | a,d |
| 12 (CF-6a) | 13 | a,f |
| 13 (CF-6b) | 8 | a,f,g |
| 14 (CF-7a) | 6 | a,d,f,g |
| 15 (CF-7b) | 7 | c,f |
| 16 (CF-7c) | 12 | c,f |
| 17 | 9 | ? |
| 18 | 16 | ? |
| 19 | 20 | i,j |
| Total=183 |
DNA is available from named families
Breed Codes
a, Mixed Poodle-Beagle
b, Mixed Poodle-Norwegian Elkhound
c, Purebred Miniature Poodle x Toy Poodle
d, Purebred Beagle
e, Mixed Siberian Husky-Beagle
f, Mixed Beagle - Norwegian Elkhound - Irish Setter
g, Mixed Norwegian elkhound - Irish setter
h, Mixed Irish setter - Beagle
i, Purebred border collie
j, Purebred Newfoundland
A subset of the Cornell Canine Reference Families are available to any group proposing to contribute mapping data to the canine map. Contact Dr S. Hannah at Ralston-Purina for further information.