MDR1 / Multidrug sensitivity (ABCB1-related) - Dog

This analysis examines the ABCB1 c.228_231del variant, which is associated with MDR1-related drug sensitivity in dogs. The ABCB1 gene encodes P-glycoprotein, a transport protein involved in distributing certain medications and helping limit their entry into the central nervous system.

If a dog carries this variant, the function of that transport system may be reduced. As a result, certain drugs, including ivermectin and other compounds that depend on P-glycoprotein transport, may cause an increased risk of adverse reactions. Dogs with two copies of the variant generally have the highest risk. Dogs with one copy may also show increased sensitivity, often with milder or more variable effects.

The test shows whether your dog carries zero, one, or two copies of the tested variant. This can help support careful interpretation together with your veterinarian when selecting or assessing medication. The result is also relevant for breeding, because the variant is inherited as an autosomal trait and can be passed on to offspring.

• Zero copies: the tested variant was not detected.
• One copy: the dog is a carrier and may have increased sensitivity to certain medications.
• Two copies: the dog has the highest genetic risk of MDR1-related drug sensitivity.

This analysis supports careful interpretation for treatment and breeding decisions, but the result should always be considered alongside the clinical context, the medications used, and veterinary guidance.