MDR1
This article was originally produced by ourselves in 2009
For a number of years now we have known that collies are sensitive to certain drugs. MDR1- The Multi Drug Resistance Gene. The gene is responsible for pumping drug and toxins from the system however dogs who carry the MDR1 gene cannot do this, therefore resulting in serious health problems that can include death if given the wrong drugs. If these toxins are not being flushed out of the system then of course it can cause severe problems for you dog.
If you have a dog who has been tested and results as MDR1 +/+, then the dog is genetically clear of the mutation that causes the problems. If your dog results as MDR1 +/- , then the dog is a carrier and is still carrying a mutation gene. The dog only has one clear gene. If your dog results as MDR1 -/- then your dog is non genetically clear of the mutation.
We know through various testing that has been done in Laboratories that when a group of drugs that come under the invermectin group are given to double mutant animals then the results can be fatal. The animal cannot pump the toxin out if its system so therefore it is left in the body and has already started to cause problems for your animal. The only way we can save our animals from ill health or even a fatality is to make sure that we are aware of the dogs MDR1 status. That way we can ensure what we give our dogs are completely safe.
For double clear dogs then there is no problem and if this dog were bred to another double clear then the resulting off spring would be clear by parantage. If a double clear was however put to a clear carrier the the result could be some clear puppies or some carriers. A carrier does have one mutation gene and therefore passes this on as it breeds. If two such carriers are bred then the result can be in both double clears, clear carriers and also not forgetting double mutants, as both parents will be passing on a clear gene and an affected gene so therefore can produce all three. If two dogs that are double mutants are bred then the result will be double mutant puppies. The mutant gene is easy to keep out of our lines by using dogs and breeding from dogs who are double clears. However, we must still use clear carriers and double mutants to eradicate this from the gene pool. Provided that you know your dogs MDR1 status then you will know what drugs that you can give your dog and what drugs you cannot. And also for those who do breed, this is crucial information that they will seek to know for their breeding stock.
The key here is not to be ignorant for that elegant and regal collie that you have always wanted as a child. If you do not know your dogs status then how will you know what to treat your dog with if it becomes ill. You could potentially save your dogs life by knowing the status and I would encourage all collie owners to have their dogs screened for MDR1. It s a simple DNA scrapping on the inside of the cheek. It does not harm your dog or put your dog under any stress what so ever but it does save any future heartache that you may encounter should your dog become ill and need medical intervention. It doesnt matter whether your dog is clear, carrier or double mutant – provided you know what your dog is then you will know exactly what medical substances your dog can or cannot get and in the case of your dog being affected then automatically your dog can be treated with an alternative brand that will be just as effective as any other drug that your dog would have got if it had been double clear.
