As a consequence of unregulated breeding, historical breeding standards, pure chance, and a host of other factors, almost all dog breeds are prone to genetic diseases. Most dog owners are aware of one or two that are common in their pet’s breed. Some very dedicated owners may know all the common genetic diseases within that breed, and even take steps to test for them. This raises the question of which dog breed has the most genetic problems?
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What is a Genetic Disease?
A genetic disease is a disease that occurs as a result of a dog’s genes. When dogs reproduce, some of the genes (the genetic codes to create life) from the mother and father are mixed together to create the complete puppy. Every gene contains instructions for a certain aspect of the puppy, from height to nose length to colour to temperament and more. Some genes are dominant and will always express their function. Other genes are recessive and will only express their function if paired with similar recessive genes. Many recessive genes contain defective genetic code that, when expressed, lead to an increased chance of genetic disease.
As a result of frequent inbreeding within dogs (some dog breeds are so inbred their functional populations are less than 100 individuals, as all the genetic codes are the same), once rare double-recessive gene carrying dogs are more common. This means certain genetic diseases are more likely to be seen.
This means the code for genetic disease is almost always something a dog is born with. Carrying the code does not guarantee the dog will get the disease in later life, as many diseases require other factors too, such as health, age, gender, diet and more. But dogs with these genes may be more prone to certain diseases. Some dogs carry half of the defective genes; making them ‘carriers’ that cannot get the disease themselves, but can pass them on to offspring.
Dogs With Many Genetic Diseases
This next section will discuss common dog breeds and their genetic diseases. It is by no means exhaustive, but will emphasise how many breeds have many health conditions.
French Bulldogs
An increasingly common breed thanks to social media and celebrity culture, the Frenchie unfortunately carries a huge number of genetic health issues. This means the mean life expectancy for these dogs is far below that of dogs of a similar size.
Chief among these is BOAS, or brachycephalic obstructive airway syndrome. As a result of breeding for shorter and shorter faces, many Frenchies have snouts far too short to have a comfortable life. Frenchies with BOAS have very narrow airways, as the normal soft tissue fitting into the smaller space blocks the passages, making every breath a struggle. This causes their distinctive snuffling noises. BOAS causes snoring, sleep apnoea, exercise intolerance, excessive panting, heat intolerance, gastric reflux, gagging, increased risk of heatstroke and even higher risk of death. Furthermore, the shortened face makes them vulnerable to skin, eye, ear, spine, mouth and breeding issues. Many dogs need multiple surgeries before they are adults just to function normally.
On top of this major issue, Frenchies are also prone to spinal dysplasia; as a result of their corkscrew tails, hip dysplasia, patella luxation, skin fold disease, juvenile cataracts and high levels of uric acid in the blood that promote bladder stone formation.
Boxers
A strong working dog and loveable family pet, the boxer is also well known for its wide range of serious genetic diseases. Probably the most infamous are their heart conditions. As a large-breed dog, boxers are more prone to dilated cardiomyopathy (DCM). But they also have their own collection of heart diseases called Boxer cardiomyopathies. These can lead to strain on the heart, raised heart and breathing rate, abnormal heart beats, fluid build-up, exercise intolerance, collapse, heart failure and death.
Cancer is the other most common cause of death in boxers. Though cancer rarely forms in infancy, certain genes seem to make boxers more prone than other dogs. These can include lymphoma, osteosarcomas, mast cell tumours and brain tumours. As above, many other factors will also affect a boxer’s likelihood to get cancer.
Boxers are also at a higher risk of hip dysplasia, hypothyroidism, eye disease, juvenile kidney disease, allergies and bloat, as well as risks associated with being brachycephalic (though not as severe as French bulldogs
Cockapoos and Similar Poodle-Crosses
It seems all the rage now to cross poodles with other dogs, such as Cocker spaniels, Labradors and Cavalier King Charles spaniels. As well as claims these dogs can be hypoallergenic. (This is a myth – no dog is hypoallergenic. But those with constantly growing fur like poodles do shed less). The crosses are often claimed to be healthier due to their mix. We have written an article before on the health of purebred vs mixed breed dogs, and the jury is still out. After all, many poodle-crosses are bred without regulation, meaning the spread of genetic diseases may occur more frequently than in other breeds that are regulated. We are even finding that poodle-crosses can inherit genetic diseases from both breeds.
Progressive retinal atrophy is a common genetic disorder in poodles, where the retinas of the eye start to die, resulting in blindness. There is often no cure, and the dog and owner must manage being blind for life. We are seeing this in cockapoos now too. Similarly, glaucoma, a condition where the pressure in the eye starts to rise, can be seen as well. In end-stages, this can cause blindness too, but we can usually manage the glaucoma before it develops to this stage.
Familial nephropathy, a urinary condition where the kidney tissue starts to die, resulting in a build-up of waste products in the blood, increased urination and thirst, and vomiting issues, can also be seen in pure and mixed-poodle breeds. Poodle-crosses can also be prone to Von Willebrand disease; a blood condition that prevents proper clotting of the blood. This leads to an increased risk of bleeding and blood loss.
These dogs can also be prone to skin and food allergies; though it is unknown whether this is genetic or purely environmental.
Labrador Retrievers
The most popular breed in the UK, and for good reason, the Labrador is a perpetually smiley bouncy dog. But as with all breeds, Labradors are not exempt from their own genetic diseases. Many are born with elbow and hip dysplasia, causing skeletal issues later in life. It is known that most Labradors are also genetically more prone to obesity, making their mobility issues worse. Good weight management and early identification of these conditions can reduce the severity in later life.
They are also prone to a number of eye conditions, including progressive retinal atrophy, cataracts, corneal dystrophy and retinal dysplasia, affecting their vision. Labs are also prone to exercise- and muscle-related genetic diseases, like myasthenic syndrome, degenerative myelopathy, exercise-induced collapse and pyruvate kinase deficiency.
Dachshunds
Known for their sausage-like shape, this unique feature causes a number of genetic skeletal health conditions associated with the breed. The most well known is intervertebral disc disease, where poor quality spinal discs mean these dogs can have painful backs and are prone to sudden paralysis after jumping, twisting, exercise or even being picked up. IVDD can require months of rehabilitation, risky spinal surgery or even euthanasia. Daxies are also prone to patella luxation and brittle bone disease.
On top of these issues, dachshunds can have genetically linked hearing and vision issues, epilepsy, Cushing’s disease, allergies, autoimmune diseases, and heart disease.
What’s the Verdict?
Though these five breeds (or crossbreeds) are well known for their genetic diseases, we could have selected any number of breeds as examples in our list. And that’s the point, there really isn’t an answer on which breed has more genetic diseases. It varies so much and new genetic diseases are being identified all the time. Certainly some breeds have worse overall health than others, part of which will be caused by high incidence of genetic diseases (here, French bulldogs are sadly bottom of the list). We really cannot identify which breed has more. So rather than arbitrarily list breeds based on their genetic diseases, we will spend the rest of the article discussing how you can limit the incidence of genetic diseases and improve the health of dogs as a whole.
How to Avoid Genetic Disease When Adopting a Dog
First, consider the breed of dog you want
And whether it will fit with your lifestyle and be the right temperament, think of the health of the breed in general. All breeds have genetic diseases, as we discussed above, but certain breeds are, unfortunately, just too unhealthy to recommend. These mainly include brachycephalic breeds, including Frenchies, pugs, cavaliers, Shih tzus and other breeds, as well as certain giant-breed dogs. If this sort of dog is the one you desire, we urge you to do your research and be prepared for the diseases you will have to manage.
Next consider where to purchase from
The common options are from a professional breeder, an amateur breeder, charities and shelters, friends and family, online or from abroad. We urge you to check local charities first, as many are overwhelmed with the numbers of dogs; many of whom would love a new home and may even have been checked for common problems.
If you do want to purchase ‘new’, then do thorough research. Online adverts, from abroad, families and friends and amateur breeders will likely have little to no thought regarding genetic diseases. The risk of a puppy having these is higher. Purchasing here can also encourage the practices and result in even more unregulated breeding.
Licensed breeders are acceptable, but please inspect the premises first; ensure full genetic testing has been performed, and ensure the health of the mum and dad is known. Good breeders will also calculate the inbreeding coefficient of the match, which will estimate the likelihood of interbreeding and thus the risk of genetic diseases.
Consider whether you want a pure or mixed-breed dog
As we mentioned above, numerous studies are unable to conclude whether one is healthier than the other. The main advantage with purebred dogs is their proven lineage, meaning you can assess whether the line is healthy. Unfortunately, many lines will not be healthy, which has resulted in the incidence of genetic diseases in the first place. But with this proven lineage, steps are being taken by many breeders to filter out defective genes.
Once you have your own dog, you should also inquire about any other genetic testing your vet recommends
Although at this stage testing will not entirely stop your dog getting these diseases, by being aware of the risk you can reduce their chance. Furthermore, if you were planning to breed from them, it may show whether it is safe to do so. Early testing and regular monitoring can help prevent the worst of many of these diseases.
Finally, as an aside, never purchase dogs from puppy farms, those illegally imported or without seeing the parents and where the puppies were born
Too many dogs are being illegally bred, which increases the risk of inbreeding and thus genetic diseases. By purchasing from these people, you are creating demand and encouraging the practice, leading to more diseased, malnourished and abused dogs. No matter how much you think you are ‘saving’ one of the dogs, you are just creating the demand. If you are concerned for the welfare of any animal, please report it to Trading Standards, the RSPCA or the police.
Further Reading:
- Dog longevity: How long will my pet dog live? – BBC
- Mixed or Purebred Puppy: Which is Better? – PetMD
- BOAS – breathing problems in flat-faced dogs – PDSA
- What is Brachycephalic Obstructive Airway Syndrome (BOAS)? – RSPCA Knowledgebase
- Breeding bad – the true cost of irresponsible pet breeding – Blue Cross
- What animal welfare problems are associated with dog breeding? – RSPCA Knowledgebase
- Is a Mastiff a healthy breed, and do they make good pets?
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