Acuracy of Genetic Testing in Dogs

Hello, Summarians!

How do we interpret the direct-to-consumer genetic tests that can be done on pets? Sadly, there are few studies to help us in this regard but here is one that can help.

Please give me feedback on ways I can make it more useful to you.

If it is valuable to you please consider sending it on to a friend 😄 

Accuracy of Genetic Testing in Dogs

This study delves into the growing field of direct-to-consumer (DTC) genetic testing for canine ancestry, reflecting a broader trend in both human and veterinary genetics where individuals seek genetic insights outside traditional clinical settings. By examining six commercially available DTC dog genetic tests as of the end of 2021, the study aimed to assess the influence of non-genetic information (specifically, photographs of dogs) on the ancestry estimates provided by these tests. The methodology involved submitting DNA samples from 12 purebred dogs to each company, half of which were accompanied by a photograph of the DNA donor dog and the other half by photos of different purebred dogs, to test if the visual information affected the breed predictions. 

The findings revealed significant disparities in breed ancestry predictions among the companies, with some tests producing results that were influenced by the photograph provided. This suggests a potential compromise in the genetic analysis's integrity, raising concerns about the reliability and transparency of these DTC services. Notably, Accu-Metrics displayed particularly poor performance, often failing to correctly predict the dog's breed based on genetic information alone. In contrast, other companies showed high accuracy in identifying the registered breed of the DNA donor, indicating a robust genetic analysis framework. 

Furthermore, the study highlighted the broader implications of such genetic tests, including potential social and economic consequences for dog owners, particularly in contexts where breed ancestry can affect home insurance coverage and housing eligibility. This underscores the importance of accurate and reliable genetic testing and the need for consumers to approach DTC test results with skepticism. 

Lastly, the study sheds light on the challenges faced by veterinarians, who may need to guide pet owners through the complexities of DTC genetic test results, underscoring the necessity for increased education and awareness about the limitations and potential pitfalls of these tests. This comprehensive evaluation serves as a cautionary tale about the burgeoning DTC genetic testing market, emphasizing the need for standardization, transparency, and regulatory oversight to ensure accuracy and reliability in genetic ancestry predictions for dogs. 

Rando, H. M., Graim, K., Hampikian, G., & Greene, C. S. (2024). Many direct-to-consumer canine genetic tests can identify the breed of purebred dogs. Journal of the American Veterinary Medical Association https://doi.org/10.2460/javma.23.07.0372 

Bottom line — This helps with some useful data.

Mesotherapy for Arthritis in Dogs

Osteoarthritis (OA) is the most commonly diagnosed musculoskeletal disease in veterinary medicine.1 The disease is particularly impacting in working dogs, their performance, and overall quality of life (QOL).2 Osteoarthritis is a low-inflammatory chronic disease3 and is a cause of pain.4 Managing the disease can be challenging, requiring a multimodal approach.5 A wide range of approaches have been developed and tried for the management of OA, which speaks to the challenges of successfully managing the disease. Nonsteroidal anti-inflammatory drugs remain the most common first line of approach for the management of OA, with multiple compounds being available.6 More recently, a growing number of alternative approaches have been described, such as a growing array of oral joint supplements,7 compounds administered through intra-articular injections,8–12 biological products,13–16 photobiomodulation,17 and more. Intradermal therapy, commonly referred to as mesotherapy, is a technique used to inject a drug into the superficial layer of the skin.18 This technique creates a small deposit of medication in the skin, with the intent to modulate the drugs’ kinetics, slow absorption, and prolong the local mechanism of action.18 The use of mesotherapy for the management of painful musculoskeletal conditions has been described in humans,19 horses,20 and dogs.21–23 A recent study24 showed that a multiple-session mesotherapy protocol was superior to an NSAID in the management of hip OA. Different substances have been described in mesotherapy protocols and for the management of OA. Traumeel is a homeopathic combination formula of 12 botanical and 2 mineral substances with demonstrated anti-inflammatory, anti-edematous, and anti-exudative effects.25 In humans, it has been described as not inferior to NSAIDs in the treatment of epicondylitis, trauma, pain, and other injuries.26 Its use has been described in horses and dogs.20,27 Glucosamine has been characterized as a chondroprotective agent due to a modulatory effect on the metabolic activity of chondrocytes. In vitro, it has been shown to have the ability to reduce matrix molecule degradation and enhance its synthesis28 and is usually administered in combination with chondroitin sulfate, the major glycosaminoglycan found in the cartilage of moving joint surfaces.29 Reports on the efficacy of these 2 compounds in the management of OA show different levels of clinical improvement,30 and there is some evidence suggesting that long periods of administration are required. 

Alves, J. C., Santos, A., & Lafuente, P. (2024). Evaluation of different substance combinations in a multiple-session mesotherapy protocol for the management of osteoarthritis in dogs: a retrospective study. Journal of the American Veterinary Medical Association  https://doi.org/10.2460/javma.23.10.0588 

Bottom line — Early results are encouraging but more study is needed.

Biomarkers for Meniscal Injury

This study explores the potential of using nuclear magnetic resonance (NMR) spectroscopy for identifying biomarkers of meniscal injury in the synovial fluid (SF) of dogs with cranial cruciate ligament rupture (CCLR). Given the high incidence of meniscal injuries in dogs with CCLR and the challenges associated with diagnosing these injuries, especially postoperatively, there's a need for non-invasive diagnostic methods. Traditional imaging techniques, though useful, are limited by their availability, cost, and sometimes, accuracy. Surgical diagnosis carries risks and may lead to unnecessary procedures if no injury is found. 

The research leverages NMR metabolomics to investigate changes in the SF metabolomic profile of dogs with CCLR, with and without concurrent meniscal injuries. It hypothesizes that the presence of meniscal injuries alongside CCLR would alter the metabolomic profile of SF, particularly increasing NMR mobile lipids. NMR spectroscopy has shown promise in identifying biomarkers for various joint pathologies in humans and animals by analyzing metabolic changes and has been found to be rapid, non-destructive, and relatively inexpensive. 

The findings revealed significant increases in NMR mobile lipids in the SF of dogs with both CCLR and meniscal injuries compared to those with CCLR but no meniscal injury, or those with neither condition. This increase in lipids could be attributed to damage to cellular phospholipid membranes, lipid release due to cell necrosis or apoptosis, or as part of an inflammatory response to meniscal tears. Other metabolites, such as those involved in glycolysis and the tricarboxylic acid cycle, did not show significant differences between the groups, indicating that the lipid changes were more specifically associated with meniscal injuries. 

Despite these promising results, the study faced limitations such as the lack of a balanced control group, potential biases due to minor blood contamination in some SF samples, and unaccounted variables like diet and exercise. Nonetheless, this research marks a significant step towards developing a minimally invasive, inexpensive diagnostic test for meniscal injuries in dogs through arthrocentesis, potentially reducing the reliance on more invasive surgical diagnostic methods. Further research is needed to identify the specific lipid species involved and to validate these biomarkers in larger, more diverse cohorts. 

Pye, C.R., Green, D.C., Anderson, J.R., Phelan, M.M., Fitzgerald, M.M., Comerford, E.J. and Peffers, M.J. (2024), Determining predictive metabolomic biomarkers of meniscal injury in dogs with cranial cruciate ligament rupture. J Small Anim Pract, 65: 90-103. https://doi.org/10.1111/jsap.13688 

Bottom line — A potentially less invasive way to assess injury.

Just putting things in perspective …