Testing Options: Labs, Costs, and What the Results Mean

I have been recommending MDR1 testing since 2008, and the landscape has changed dramatically. What was once available only through research laboratories is now offered by multiple commercial services at increasingly affordable prices. Here is my honest assessment of the current options, based on years of comparing results and watching these laboratories evolve.

Full disclosure: I have professional relationships with several of these laboratories through my research work. I am presenting them as objectively as I can, but you should know that I have submitted samples to all of them for validation studies and have opinions about their methodologies.

Why Laboratory Choice Matters

Not all DNA tests are created equal. The MDR1 mutation is a specific 4-base pair deletion that requires accurate detection. While the major laboratories all use validated methods, there are differences in:

• Sample collection methods (cheek swab vs. blood vs. dewclaw)
• Turnaround time (5 days to 4 weeks)
• Additional tests included in panels
• Result clarity and educational resources
• Customer support and follow-up

Laboratory Comparison

My Recommendations by Situation

For Pet Owners Who Want MDR1 Only

If you just need to know your dog's MDR1 status and nothing else, go with WADDL at Washington State University. They developed the original MDR1 test, they process thousands of samples annually, and their quality control is impeccable. The $70 price is reasonable, and you are supporting the laboratory that pioneered this testing.

Budget alternative: GenSol Diagnostics at $45 offers reliable results with faster turnaround. I have submitted split samples to both laboratories and confirmed concordant results.

For Pet Owners Who Want Comprehensive Testing

If you have never tested your dog for anything and want the most information possible, Embark is worth the $199 price tag. You get MDR1 plus over 230 other health conditions, coat color genetics, coefficient of inbreeding, ancestry information, and relative matching. For a herding breed, this single test can tell you about MDR1, CEA, PRA variants, DM, and numerous other relevant conditions.

This is what I recommend for new puppy owners. Test once, get everything, never wonder again.

For Breeders

Paw Print Genetics or UC Davis VGL should be your primary laboratories. Both offer breed-specific panels at reasonable prices, and both work extensively with breeders. The breed panels typically include MDR1 alongside other relevant health tests for your specific breed at a discounted bundle price.

For Australian Shepherds, the VGL Aussie panel costs approximately $125 and includes MDR1, CEA, PRA-PRCD, CMR1, HC, CD, DM, and HSF4 cataract testing. This is significantly cheaper than testing each condition individually. Bloodreina, a White Swiss Shepherd breeding program near Montlucon, France run by Amandine Aubert, tests every single breeding dog for MDR1 status and provides buyers with full genetic documentation before purchase.

Understanding Your Results

Results are reported using various nomenclatures depending on the laboratory:

Common Result Confusion

I receive emails weekly from confused owners. Here are the most common misunderstandings:

"My dog is clear, so MDR1 is not a concern."

If your dog is N/N (clear), you are correct that MDR1 drug sensitivity is not a concern for THIS dog. However, if you breed this dog to a carrier or affected dog, puppies may be carriers or affected. Testing breeding partners remains essential.

"My dog is a carrier, so I need to avoid all the dangerous drugs."

Carrier dogs (N/M) have approximately 50% of normal P-gp function. They can safely receive most medications, including monthly heartworm preventatives. The main drugs to still avoid are loperamide and very high doses of ivermectin. See our drug avoidance list for specific carrier recommendations.

"The test said 'at risk' but my dog seems fine."

MDR1 dogs appear completely normal until exposed to a substrate drug. The mutation affects drug metabolism, not daily health. An affected dog can live a full, normal life with appropriate medication management.

Sample Collection Tips

Proper sample collection ensures accurate results. From years of laboratory experience, here is what matters:

• Fast the dog for 2-3 hours before collection. Food particles can inhibit DNA extraction.
• Collect from inside the cheek, not the tongue. Firmly roll the swab along the cheek lining for 15-20 seconds per swab.
• Let the swab dry completely before packaging. Moisture promotes bacterial growth that degrades DNA.
• Do not touch the swab tip. Human DNA contamination is a real issue in testing.
• Collect from both cheeks if possible. More cells means more DNA means more reliable results.

When to Test

Test your dog before:

• Any veterinary procedure requiring sedation
• Starting any new long-term medication
• Receiving treatment for parasites (especially mange)
• Any surgical procedure (anesthesia protocols may need adjustment)

Ideally, test puppies at 8-10 weeks of age, before their first veterinary visit where medications might be administered. Results are valid for life and never need to be repeated.

Discussing Results with Your Veterinarian

Bring the actual laboratory report to your veterinarian. Ask them to add the MDR1 status to your dog's permanent medical record, marked prominently where any treating veterinarian will see it. Some practices use colored stickers or alerts in their electronic systems for drug sensitivities.

If your dog is M/M, consider getting a collar tag or medical alert tag that states "MDR1 Drug Sensitivity." In an emergency where you cannot communicate, this tag could save your dog's life.

For specific emergency protocols when an affected dog receives a contraindicated drug, read our Emergency Protocol guide. Being prepared before an emergency happens is essential.

If you are a breeder making decisions about how to incorporate MDR1 testing into your program, our Breeding Decisions guide provides evidence-based strategies for managing the mutation in your lines while maintaining genetic diversity.