HGTD This Week, 7 Aug 2020: Canine Crime Scene Investigators

When we think about genetic testing, we often focus on how it can be a tool to improve health and welfare - generally centered around breeding for health or finding more about the health or potential health risks for an individual dog. Knowing about health risks that are especially relevant to specific breeds or dog types makes testing even more powerful in helping reduce risks of disease or undesirable traits (see Breed Relevancy Ratings). Most commonly, genetic screening and diagnostic testing focuses on: disease tests, breed estimation tests, diagnostics, parentage/paternity, inbreeding estimations, etc. (search for genetic tests and providers, here).

This week, I received a very interesting question from a DogWellNet.com user, who wanted to know if genetic testing could help them with a dog attack incident. Their dog had been bitten, and they wanted to know if genetic testing could be used to identify the attacking dog, using saliva from the collar. The short answer is… probably not, but maybe not for the reasons you think. In principle, it should be possible to extract DNA from saliva from a surface like a dog collar. The challenge is that, even with a genetic profile:

• You won’t know if the profile is from the attacking dog, or some other dog your pet has met at a dog park, on a walk, at the vet’s…
• Without a profile of a known dog to compare it to, you won’t be able to identify the dog (and therefore owner)

This is because dogs are generally not required to be registered with a genetic fingerprint. So, unless you know the dog and the dog's owners, it is impossible to confirm identification using DNA alone - much like the challenges in human criminal DNA identification. 

This brings us around to thinking about some of the more forensic things genetic testing can, and cannot do:

Can do:

• Act as a permanent identification for an individual dog (genetic profiling) 
• Determine parentage, when relatives’ profiles are known for comparison 
• Comment on the risks of specific genetic mutations for specific diseases (disease/phene screening testing)
• Aid in the diagnosis of specific risks/diseases (only with diagnostic testing as opposed to screening testing)

Cannot do:

• Identify a specific dog, without that dog’s genetic information/owner being on an accessible registration list
• “Prove” that a dog is responsible for an action, without other evidence
• Be used to make “permanent” decisions (e.g. euthanasia) on its own, without other veterinary health information, and welfare considerations

While there are plenty of incredibly useful things genetic testing can do, beyond genetic screening tests, it is really important to consider why you are testing and how you are going to use any test results. As with any tool, genetic testing has its limitations. 

Want to go further?  Check out this blog - Confidentiality and Genetic Testing: more benefits and risks - by IPFD CEO Dr. Brenda Bonnett, looking a other parallels and challenges with the human situation.  Relevant to the discussion above - confidentiality and availability of identifying information is an important issue to consider.

Or explore the whole new world of 'poop forensics' :  Dog Poop DNA Tracking Introduces Spy Tech to Our Backyards.  (IPFD disclaims any responsibility for the information presented there!)

Photos: pixabay (cover photo): G. Fring (image) via Pexels