Genetic Diseases by Breed: What Is Your Dog or Cat Prone To?

How breed predisposition works and where this data comes from

A predisposition means a breed gets a condition more often than the general pet population. Some are single-gene diseases with a DNA test, where two copies of the faulty gene mean the animal will get sick (progressive retinal atrophy, von Willebrand disease, polycystic kidney disease in cats). Most are complex: many genes plus body shape, growth rate, weight and environment (hip dysplasia, cruciate rupture, atopic dermatitis, cancer). For the complex ones, no test can promise a pup is clear, but parental screening still shifts the odds a long way.

The lists in this tool are compiled from breed-club health surveys, the UFAW genetic welfare problems database, the OFA and BVA/Kennel Club screening schemes, published breed-prevalence studies (including the UK VetCompass programme and the UC Davis desexing cohorts) and the DNA test catalogues of the major laboratories, filtered by what an emergency and general practice vet actually sees walk through the door. Tiers are a clinical judgement of how common and how serious a condition is in that breed, not a precise percentage, because honest percentages vary by country and bloodline.

Common genetic diseases by dog breed

The three headline risks for the most popular breeds. Select the breed in the tool for the full list, signs, tests and emergencies.

Common genetic diseases by cat breed

Cats have fewer breed-linked diseases than dogs, but the ones they have are serious and several have cheap DNA tests.

DNA tests, screening schemes and what they can and cannot tell you

A DNA test reports the animal’s copies of one specific gene variant. Clear means it will not develop that form of the disease and cannot pass it on; carrier means healthy but can pass it on; affected (two copies) means it will usually develop the disease. This works beautifully for simple recessive conditions such as PRA, degenerative myelopathy, MDR1 drug sensitivity, PK deficiency in cats and PKD in cats. A cheap combined breed-identity and health panel on a crossbreed or rescue is worth doing purely for MDR1 and DM.

What DNA cannot do is clear a dog of hip dysplasia, cruciate disease, allergies, epilepsy, most cancers or heart muscle disease, because those involve many genes. For these, screening schemes exist instead: hip and elbow scoring by x-ray, annual eye certificates from a veterinary ophthalmologist, echocardiograms for HCM in cats and DCM or SAS in dogs, BOAS functional grading for flat-faced breeds, BAER hearing tests for litters of white or merle pups, and MRI grading for syringomyelia. A responsible breeder does the tests relevant to their breed and shows you the certificates without being asked twice.

The heart mutations in Maine Coons and Ragdolls deserve a specific warning: a negative MYBPC3 test does not mean the cat will not get HCM, because other genes cause it too. Breeding cats need echo screening as well, and pet cats need their heart listened to every year.

Are crossbreeds and designer dogs healthier?

Partly. Crossing two breeds reduces the chance of a recessive disease only when the two breeds do not carry the same faulty gene, and it does nothing for the complex conditions the parents share. A Cavoodle can inherit mitral valve disease and syringomyelia from the Cavalier side and PRA, luxating patellas and dental crowding from the Poodle side. A Labradoodle has Labrador hips and Poodle Addison’s disease on the table. Groodles are one of the most common breeds I see for ear infections. Crossbreeds of unknown parentage are the healthiest group on average, mostly because nobody has been selecting them for extremes of shape.

The tool merges both parent lists when you choose “cross of two”, and moves a condition up a tier when both parents carry it, because that is when it is most likely to appear.

What to ask a breeder before buying a puppy or kitten

• Show me the results. Ask for the specific tests this tool lists for the breed. Certificates, not verbal assurance. “Vet checked” means a vaccination visit, not a screening scheme.
• Both parents. Hip, elbow, eye and heart screening on the dam and sire, not just the sire.
• DNA-tested to what? A “fully DNA tested” claim should name the conditions. For a Border Collie that means CEA, TNS, NCL and MDR1 at minimum; for a Ragdoll HCM and PKD; for a Persian PKD.
• How old are the parents? Late-onset conditions such as DCM, mitral valve disease and HCM only show up in older breeding animals. Older parents with clear hearts are worth more than young ones.
• What happens if the pup develops a hereditary condition? Good breeders have an answer and stay in touch.
• Meet the mother. Her breathing, gait, skin and temperament are the best preview of the pup you will own in five years.

Common mistakes owners make with breed health risks

• Treating the list as a diagnosis. Most dogs of most breeds never get most of the conditions listed. The list tells you where to look first, not what will happen.
• Waiting for the sign to go away. A limping large-breed puppy, a squinting Pug, a coughing Cavalier or a Dachshund that will not jump up should be seen the same week. The conditions on these lists are cheapest and most treatable early.
• Skipping insurance until something happens. Every breed condition that has shown a sign becomes a pre-existing exclusion. Insure while the animal is young and clean.
• Letting the animal get fat. Excess weight is the single biggest amplifier of joint disease, cruciate rupture, breathing problems, diabetes and disc disease across every breed on this page.
• Not telling the vet the breed quirk. MDR1 status, von Willebrand status, sighthound anaesthesia and Boxer or Doberman heart history change what a vet does. Keep them in the pet’s record where any clinic can see them.
• Assuming a cross is clear. See above. Test for MDR1 in anything with a herding breed in it.

Breed-linked emergencies: go to a vet now if you see

• Retching without bringing anything up, with a swelling belly (deep-chested breeds): bloat and torsion.
• Sudden inability to use the back legs, or dragging them (Dachshund, French Bulldog, Corgi, Basset, Cavalier or any cat with heart disease): disc rupture or a clot.
• Open-mouth breathing in a cat, or a purple tongue in any animal: heart failure, asthma or airway crisis.
• Collapse in the heat in a flat-faced breed: heat stroke.
• Fainting during excitement (Boxer, Doberman, Cavalier): a heart rhythm problem.
• Pale gums with weakness or a distended belly (Golden, German Shepherd, Cocker, Springer): internal bleeding or immune anaemia.
• A suddenly red, cloudy, painful eye (terriers, Cocker, Basset, Husky, Shar Pei, brachycephalics): glaucoma, lens luxation or a deep ulcer.
• Straining to urinate and passing nothing (Dalmatian, Bulldog, Miniature Schnauzer, any male cat): blockage.
• A seizure lasting over 5 minutes or repeating within a day.
• Collapse with vomiting and bloody diarrhoea in a young Standard Poodle, Wheaten, Toller, Bearded Collie or Portuguese Water Dog: Addisonian crisis.