Multidrug Resistance 1 MDR1 Test

A health screening test for your dog to determine if it carries the mutated MDR1 gene.

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What is Multidrug Resistance 1?

Multidrug Resistance 1 is inherited as an autosomal incomplete dominant disease. The MDR1 gene codes for the production of a protein known as p-glycoprotein. P-glycoprotein acts as a pump that removes certain drugs and toxins from the body. A mutation in the ABCB1 gene associated with MDR1 prohibits P-glycoprotein’s ability to limit absorption, distribution, and excretion of drugs and allows higher levels of drugs to enter the brain.

Dogs only need to inherit one copy of the MDR1 mutation to be at risk for sensitivity to certain drugs. Dogs with two copies of the MDR1 mutation can have more severe reactions such as excess salivation, tremors, anorexia, blindness and possibly death.

MDR1 affected dogs are at risk of developing neurologic symptoms from several common drugs including Acepromazine (tranquiliser), Butorphanol (pain control), Doramectin, Doxorubicin, Emodepside, Erythromycin, Ivermectin (found in heartworm medications), Loperamide (anti-diarrheal agent), Milbemycin, Moxidectin, Paclitaxel, Rifampicin, Selamectin, Vinblastine (anti-cancer agent), Vincristine and Vinorelbine.

Other medications may also cause a reaction and you should inform your veterinarian if your dog is a MDR1-carrier or MDR1-affected so they can adjust dosage or provide an alternative medication.

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Which Breeds Can Be Tested for Multidrug Resistance 1 MDR1?

The Multidrug Resistance 1 MDR1 Test can be carried out on all breeds.

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What will Multidrug Resistance 1 MDR1 Test Results Tell You?

Using a simple swab from the inner cheek of your dog, we will ascertain whether your dog carries the mutated MDR1 gene, which allows you to make an informed choice as to whether or not to breed from the dog.

Once we receive the dog’s buccal swabs, we undertake tests that will give one of three possible outcomes:

  1. A CLEAR result shows that the dog has inherited two genes from its parents that are mutation free and will not be affected by MDR1.
  2. A CARRIER result indicates that the dog has inherited one normal copy of the MDR1 gene, and one mutation. This means that the dog has an increased risk of drug sensitivity.
  3. An AFFECTED result indicates that the dog has inherited two copies of the mutated MDR1 gene from its parents and is at risk of adverse drug reactions.

Please click on the image below to view our Multidrug Resistance 1 MDR1 Test Result Chart:

Multidrug Resistance 1 MDR1 Test Result Chart

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Other Dog DNA Tests from AffinityDNA

As well as the Multidrug Resistance 1 MDR1 Test we also offer a range of inherited disease screening tests including:

Dog Allergy Testing, Dog Parentage Testing and a choice of dog DNA breed tests which include information about the personality traits and predisposition to diseases for each breed found in your dog’s DNA.

If you have any questions about the Multidrug Resistance 1 MDR1 Test for your dog, please do not hesitate to Contact our Customer Service Team who will be happy to help you.


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