Health Testing

Cone Degeneration (CD) in dogs is a condition where the cone cells in the retina, which are responsible for color vision and seeing in bright light, start to deteriorate. This leads to impaired vision, especially in bright environments, and can eventually result in complete loss of sight. The condition is often inherited and can vary in severity among different breeds.

Chondrodysplasia (CDPA) in dogs is a genetic condition that affects the development of cartilage, leading to abnormal bone growth and resulting in shorter limbs and a distinctive dwarfed appearance. This condition is caused by a mutation in specific genes and is inherited in an autosomal dominant manner, meaning only one copy of the mutated gene is needed for the trait to be expressed. Dogs with chondrodysplasia may have a normal-sized body but disproportionately short legs, which can affect their mobility and lead to joint issues. 

Chondrodystrophy (CDDY) in dogs is a genetic condition that affects cartilage and bone development, leading to shorter legs and potential spinal issues like Intervertebral Disc Disease (IVDD). This condition results from a specific genetic mutation and is inherited in an autosomal dominant pattern, meaning only one copy of the gene is needed for the trait to appear. Dogs with CDDY have a distinct appearance with a long body and short legs, and they are more prone to back problems. 

Please visit the University of California - Davis Campus Veterinary Genetics Laboratory website for more information.

Collie Eye Anomaly (CEA), also known as collie eye defect, is a genetic condition that affects the development of the eyes in certain dog breeds, particularly Collies. This condition can lead to various eye abnormalities, such as underdeveloped optic nerves, retinal detachment, and abnormal blood vessels in the retina. While some dogs with CEA might have mild vision problems or no noticeable symptoms, others can experience
significant vision loss or blindness. It is inherited and cannot be cured, but regular eye check-ups can help manage the condition. It is also commonly found in breeds such as Shetland Sheepdogs, Border Collies, Australian Shepherds, and Nova Scotia Duck Tolling Retrievers. These breeds share similar genetic backgrounds with Collies, making them susceptible to the condition.

Please visit the University of California - Davis Campus Veterinary Genetics Laboratory website for more information.

Degenerative myelopathy (DM) is an inherited (autosomal recessive, above) progressive disease that affects the spinal cord in dogs, leading to muscle weakness and loss of coordination, starting in the hind legs and eventually causing paralysis. It typically manifests in middle-aged to older dogs, around 8 to 14 years old. Early signs of degenerative myelopathy in dogs could include a subtle loss of coordination and weakness in the hind
legs, which might cause the dog to drag its paws or stumble occasionally. You might also notice the dog having difficulty standing up, especially after lying down, or a swaying gait when walking. As the condition progresses, these symptoms become more pronounced, leading to muscle atrophy and increased difficulty in mobility. The disease progresses gradually, often taking several months to a few years for a dog to become fully affected.

Hereditary cataracts (HC) in dogs are a genetic condition where the lens of the eye becomes cloudy, leading to vision impairment or blindness. Normally, a dog’s eye lens is clear, allowing light to pass through and focus on the retina, enabling clear vision. Cataracts can manifest at birth or develop later in life, often in young or middle-aged dogs. This condition is caused by mutations in specific genes, such as the HSF4 gene. If a dog inherits one mutated gene, it may have a milder form of cataracts, while inheriting two mutated genes typically results in more severe cataracts. 

Hyperuricosuria (HUU) in dogs is a condition where there is an excessive amount of uric acid in the urine, leading to the formation of painful bladder or kidney stones. Normally, dogs excrete low levels of uric acid, but in HUU, this process is disrupted. This condition can cause difficulty urinating, frequent urination, and blood in the urine. HUU is inherited as an autosomal recessive trait, meaning a dog must inherit two copies of the mutated gene (one from each parent) to be affected. Dogs with two mutations are more likely to develop stones, which can be life-threatening if they block the urinary tract. Though sometimes found in females, it manifests more commonly in males due to anatomical differences. Not all dogs with mutations in both copies of the gene will have symptoms of the disease, though they would have increased uric acid excretion in the urine. 

MDR1, or Multidrug Resistance 1, is a genetic mutation in dogs that affects the ABCB1 gene. This mutation is primarily found in herding breeds like Collies and Australian Shepherds. Dogs inherit this mutation from their parents, and it can cause them to be overly sensitive to certain medications. The mutation affects a protein called p-glycoprotein, which normally helps to pump drugs out of the brain and other organs. When this protein doesn’t work properly, drugs can build up to toxic levels, leading to severe and sometimes fatal reactions. Genetic testing can identify dogs with this mutation, allowing for safer medication choices.

*Drugs known to cause neurological signs related to the MDR1 mutation: Acepromazine, butorphanol, doxorubicin, emodepside, erythromycin, ivermectin, loperamide, milbemycin, moxidectin, rifampin, selamectin, vinblastine and vincristine.

MDR1 is Autosomal Incomplete Dominant, which means they only need to inherit one copy of the mutated gene to be at an increased risk. While it’s more common for dogs with two copies of the mutated gene to have adverse reactions, carrier dogs can also experience drug sensitivities and dosages would need to be adjusted.

**It has happened that clear dogs have reacted to some of these drugs. We strongly recommend treating ALL Miniature American Shepherds as though they are MDR1 affected, even if they are genetically clear for it.  

Neuronal Ceroid Lipofuscinosis 6 (NCL6) is a genetic disorder in dogs that affects the nervous system. It causes an abnormal buildup of waste compounds in nerve cells, leading to symptoms like seizures, loss of coordination, and behavioral changes. This disease is inherited in an autosomal recessive manner, meaning both parents must carry the gene for a puppy to be affected. Symptoms usually appear between 6 months and 4 years of age.  Unfortunately, there is no cure, but supportive care can help manage the symptoms and
improve the dog’s quality of life however, affected dogs are often humanely euthanized by 2 years of age due to progression of the disease. 

Progressive Retinal Atrophy (PRA) - Progressive Rod-Cone Degeneration (PRCD) is a genetic eye disorder in dogs that leads to blindness. It starts with night blindness and progresses to complete vision loss as the retina’s photoreceptor cells (rods and cones) deteriorate. Unfortunately, there is no cure, and the condition is inherited in an autosomal recessive manner, meaning both parents must carry the gene for a puppy to be affected. Dogs with PRA-PRCD will eventually become completely blind.