Macrothrombocytopenia (MTC-R) DNA testing for the Norfolk terrier dog breed

Macrothrombocytopenia (MTC-R) DNA testing for the Norfolk terrier dog breed

Health & Safety

The Norfolk terrier is one of the UK’s remaining extant native dog breeds, and is actually the smallest of all of our working terrier dog types as well as today being a popular pet both within their home county and across the UK. Whilst Norfolk terriers are not among the most common of dogs in the UK, they are robust, lively and outgoing little dogs that are smart and adaptive, which makes them a good fit for all manner of homes and owners who can provide enough exercise and stimulation to keep the dog happy and fulfilled.

Norfolk terriers are plucky, confident and bold little dogs that are very tenacious and that can be stubborn, as well as having a strong prey drive too, which is why they became so popular as working hunting dogs. Dogs of the breed are also very loving, affectionate and entertaining, and it is certainly fair to say that they keep their owners very much on their toes!

Norfolk terriers are generally hardy, healthy dogs that don’t tend to be overly fragile or delicate, but there are a few health problems that tend to crop up within this breed more than they do in others, and that are passed on from dog to dog by means of heredity.

Some such conditions can be predicted by means of DNA testing, which means that owners of Norfolk terriers who elect to have their dogs tested for the markers of health conditions that are a known threat to the breed can find out for sure what their dog’s status is, even in affected dogs prior to them beginning to show symptoms.

DNA testing can also help breeders to ensure that they use only healthy dogs within their breeding programmes, which will not pass on the affected form of various hereditary health conditions to their own offspring.

One such hereditary health condition that can be found within the Norfolk terrier breed is called macrothrombocytopenia (MTC-R), and this is a disorder that causes a low blood platelet count in affected dogs, which is not responsive to treatment. A DNA test is available for macrothrombocytopenia in the Norfolk terrier dog breed, which identifies the status of any tested dog and that can also be used to predict what the status of any pups they might have would be too.

In this article we will explain the basics of macrothrombocytopenia (MTC-R) in Norfolk terriers, outline how the condition is passed from dog to dog, and share information on how to get your dog DNA tested to find out their status.

What is macrothrombocytopenia (MTC-R)?

Macrothrombocytopenia comes in more than one variant, each of which affects dogs that have it in different ways. The type of macrothrombocytopenia that can be found in some Norfolk terrier breed lines is the MTC-R variant, and the gene fault that causes this specific type of the disorder is different both in terms of the genes affected and how the condition presents than other forms of the condition.

Norfolk terriers with macrothrombocytopenia (MTC-R) have a low blood platelet count and may also have deformed and overly large platelets too, and this specific type of macrothrombocytopenia is perhaps most distinct from other variants of the condition in that it is not responsive to treatment.

How do Norfolk terriers inherit macrothrombocytopenia (MTC-R)?

Macrothrombocytopenia (MTC-R) in Norfolk terriers is not contagious and cannot be caught like an infection. The condition occurs due to a gene fault that has been identified as present within some dogs of the breed, and which is inherited by dogs from their parents.

However, macrothrombocytopenia (MTC-R) is inherited by autosomal recessive means, which means that the status of both parent dogs within any mating match is what determines the status of the litter; if just one parent dog carries the markers of the condition, their litter will not be affected by it.

Dogs can have a status of either clear, a carrier, or affected, and once you know the status of two parent dogs, you can work out the status of their offspring as follows:

  • Two clear parents will have a clear litter.
  • Two affected parents will have an affected litter.
  • Two carrier parents will have a litter with odds of 50% for each pup being a carrier, 25% for each pup being affected, and 25% for each pup to be clear.
  • A clear and a carrier parent will have a litter with 50:50 chances of inheriting clear or carrier status.
  • A clear parent and an affected parent will have a litter of carriers.
  • A carrier parent and an affected parent will have a litter with 50:50 chances of inheriting carrier or affected status.

How to get a Norfolk terrier DNA tested for the markers of macrothrombocytopenia (MTC-R)

If you plan to breed from your Norfolk terrier or just want to know for sure what your dog’s status is, you can ask your vet to take a cheek swab or blood sample from them to undertake DNA testing. If you intend to use this information as the basis of a mating match, please remember that both parents must be tested to enable you to work out the status of any subsequent litter.

To get your Norfolk terrier tested for the markers of macrothrombocytopenia (MTC-R) and find out their status, just ask your vet to send off the DNA sample they take to one of the designated testing laboratories in the UK that can perform the test, who will then return the dog’s results to their owner.



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