Affected Breeds
Pictured from top: Collie, Australian
Shepherd and Silken Windhound.
Approximately three of every four Collies in the United States have the
mutant MDR1 gene. The frequency is about the same in France and
Australia, so it is likely that most Collies worldwide have the
mutation. The MDR1 mutation has also been found in Shetland
Sheepdogs (Shelties). Australian Shepherds, Old English
Sheepdogs, English Shepherds, German Shepherds, Long-haired
Whippets, Silken Windhounds, and a variety of mixed breed dogs.
The only way to know if an individual dog has the mutant MDR1 gene is to
have the dog tested. As more dogs are tested, more breeds will probably be
added to the list of affected breeds.
Breeds affected by the MDR1 mutation (frequency
%)
|
| Breed |
Approximate Frequency |
| Australian Shepherd |
50% |
| Australian Shepherd, Mini |
50% |
| Border Collie |
< 5% |
| Collie |
70 % |
| English Shepherd |
15 % |
| German Shepherd |
10 % |
| Herding Breed Cross |
10 % |
| Long-haired Whippet |
65 % |
| McNab |
30 % |
| Mixed Breed |
5 % |
| Old English Sheepdog |
5 % |
| Shetland Sheepdog |
15 % |
| Silken Windhound |
30 % |
