Mutation

A mutation is a permanent change in DNA that can cause both positive traits such as coat colours and severe hereditary diseases in dogs.

For you as a dog owner, this is not abstract biology class. If your Labrador suddenly goes blind or your dachshund shows signs of paralysis, mutations are often the cause – changes in the genetic material that have been passed down through generations.

Why does my dog suddenly develop problems that its parents did not have?

Mutations arise in two ways: spontaneously due to cell division errors or through external influences such as radiation and chemicals. Many hereditary diseases are recessive – both parents must be carriers for the disease to manifest.

An example: Your female dog and the male dog show no symptoms of progressive retinal atrophy. However, both carry the mutation. Each puppy has a 25% risk of going blind.

Mutations that only manifest later in life are particularly insidious. Your Golden Retriever can be healthy for five years before a heart mutation leads to dilated cardiomyopathy.

Which mutations are common in my breed?

Every breed has its typical problem areas. This is a direct result of centuries of breeding for specific traits.

Dachshunds suffer from disc problems due to their body shape. The mutation that causes short legs simultaneously weakens the spine. In Boxers, heart mutations lead to dilated cardiomyopathy, a disease that often only becomes visible after the third year of life.

Collies frequently carry the MDR1 defect. The affected mutation makes certain medications lethal. A standard deworming agent can kill an affected Collie.

German Shepherds have a high risk of degenerative myelopathy – a spinal cord disease that begins with coordination problems in the hind legs and ends in paralysis.

When should I have a genetic test done?

A genetic test is mandatory, not optional, before breeding. Reputable breeders test for all known mutations in their breed.

As an owner, a test makes sense if your dog shows symptoms that point to hereditary diseases. The same applies if you have bought a dog without health certificates and want to know what risks exist.

An MDR1 test costs around 60 euros and can save your Collie’s life. Tests for progressive retinal atrophy cost similarly and give you planning security for the coming years.

Some vets advise against tests: “We can’t treat it anyway.” That is too simplistic. You can act preventively – avoid specific medications, adapt the lifestyle, watch for symptoms in good time.

Can positive mutations bring advantages to my dog?

Not all mutations are bad. The blue eyes of your Husky arise from a mutation. So does the merle pattern in Australian Shepherds.

Some mutations even offer protection. Rhodesian Ridgebacks have a natural resistance to certain parasites due to a specific mutation – an advantage in their original homeland, Africa.

It becomes problematic when beauty ideals promote health-damaging mutations. The extreme merle pattern can lead to deafness and blindness. Extreme brachycephaly – the flat faces of Pugs and Bulldogs – arises from mutations that cause breathing problems.

What does it mean if my dog is a “carrier” of a mutation?

Carriers have one copy of the mutated DNA but show no symptoms. For recessive hereditary diseases, you need two copies for the disease to break out.

Your dog can live healthily and still be a carrier. The problem only arises when mated with another carrier. Then the puppies have a high risk of disease.

Modern genetic tests show exactly: clear, carrier, or affected. With this information, you can make responsible breeding decisions or give your vet important clues for treatment.