Published on November 20th, 2019 | by Debbie Martin0
Doggie DNA – Appearances Can Be Deceptive
Doggie DNA, Appearances can be deceptive, so do you know what breed of dog you have? If you have a pedigree dog you should have a piece of paper detailing that last few generations of your dog’s family tree so you can say for certain who his parents were – and you may even have some family photographs from the breeder so you can see how much like his Dad he is. The breed societies and kennel clubs have long maintained records of who has fathered which puppies and who the mother was and are careful only to breed from the best of the litter. This means if you buy a pedigree dog you can be pretty sure of what you are getting.
Most dogs aren’t perfectly documented pedigrees – most are cross-breeds such as the modern “Cockerpoo” or “Labradoodle” or even good old “Heinz-57” mongrels. And even pedigree dogs can end up in rescue shelters with no record of their ancestry.
Many owners of cross-breeds and rescues like to try and guess what has gone into making their dog the way they are. They examine coat length, colour, texture and markings. They consider muzzle length, leg proportions, tail thickness and ear type. They compare the dog’s personality and temperament. And sooner or later they will decide that the dog must be part Collie or Terrier or whatever else seems to fit with the patterns they have identified. Sometimes it can remain a mystery. Any dog with a black and white coat, fairly intelligent and active is likely to be identified as “having a bit of collie in there” but the black and white coat – even the particular Collie patterning – is not unique to Collies and can easily be throw out by other combinations of parents.
Like all natural creatures, dogs exhibit variations in each generation and how the parental DNA combines can throw up a few surprises. A case recently involved a rehomed Labrador-cross. Or at least that is what their new owner was told and as the dog was short-haired with the distinctive short black coat and drop ears of a Labrador Retriever it seemed a reasonable claim. These particular characteristics of the Labrador breed are found in a number of other breeds and as they are dominant genes they are the characteristics that are generally expressed (shown) in the puppies.
In this case DNA testing showed that the dog was in fact a Springer x Cocker Spaniel on one side and a Staffordshire Bull Terrier on the other. The dominance of the short-hair gene had suppressed the long-hair spaniel coat and created a dog that had definitive Labrador tendencies. The dog’s new owner had already suspected that there was Staffie in the mix due to the extreme affection the dog displayed towards his new family.
DNA testing – for dogs?
Thanks to crime shows (and daytime television) most people are aware of the ease with which DNA can be analysed, obtained from a mouth swab or hair sample, to determine parentage. Early testing of dogs – to confirm pedigree status or parentage in the case of uncertainty – was sufficient to compare known dogs against the sample but was inaccurate when it came to identifying particular breeding if samples of the parents were not available. Some owners have had extremely dubious results – extremely large dogs being identified as being fathered by miniature breeds for example.
How does it work?
DNA testing relies on comparison of the sample with DNA from a known source. The more points at which it matches the more likely they are to have come from the same source. Thus, parentage can be confirmed by comparing the parent’s DNA with that of the offspring. Dog DNA testing services haven’t, until recently, had much of a database of samples to compare. The analysis returns the best “match” even if it is not a very good match – leading to bizarre results.
Bigger Database – Better Results
One of the largest databases of pure-bred pedigree dogs is the Wisdom Insights database and contains over 200 kennel club recognised UK and US dog breeds. The larger the database the more accurately the test can pinpoint the breeds that go into the make-up of your dog.
Does it matter?
You may be wondering if there is any point in knowing the true lineage of your much-loved mongrel. DNA testing is more than just analysing who the parents are. It can indicate what sort of personality you might expect your dog to have, what sort of traits he might display – and what sort of health problems he might suffer from.
Certain breeds have developed particular health issues and whilst responsible pedigree breeders ensure that their breeding stock are tested and examined so as not to pass on these issues it’s not necessarily the case that cross-breeds have been so carefully chosen – indeed many mongrels are the result of accidental breeding when an owner hasn’t neutered their dog.
Knowing that your pet has a breed prone to hip dysplasia, for example, means you can be more alert to issues with their joints and can obtain advice from your vet in advance on how to care for your dog to prevent any issues occurring. Other genetic tendencies that go hand in hand with breed include obesity, auto-immune disorders, heart issues, eye problems and allergies. The early stages of some health problems can be mild and, unless you are on alert for the symptoms, can be missed which lowers the chances of effective treatment should your dog develop the condition.
DNA testing is an optional extra that for most owners will simply offer confirmation of what they long suspected about the lineage of their dog. For some, however, it could hold vital clues about why their dog behaves in a certain way or provide them with a “heads-up” on health problems to look out for.
Fancy finding out more about your own dog, then we have a fab competition on our Facebook page where you can win a Wisdom Panel Kit.