Down syndrome is a fairly common genetic disorder in people, affecting 1 in every 700 babies born in the United States. It is known for causing delays in both physical and mental development. But can dogs have Down syndrome? If you have noticed physical and mental abnormalities in your dog, you might be asking yourself this question. Thankfully, we are here to answer all your Down syndrome dog-related questions. What is Down syndrome? How can you tell if your dog has it? And how do you care for a Down Syndrome dog? Keep reading to find out!
What is Down Syndrome?
Down syndrome is a human condition that causes delays in both mental and physical development. As a result, people with Down syndrome often have notable unusual facial characteristics, increased risk of heart and digestive issues, and some degree of cognitive impairment. The severity of these symptoms varies on a case-by-case basis. In humans, this condition arises when a baby is born with an extra chromosome. Hold on, what are chromosomes? Well, chromosomes are where our genes are stored in the body. In humans, we have 23 pairs of chromosomes that are found in the nucleus of every cell in our bodies. They tell our cells how to function, what proteins to produce, and which cells they need to specialize into. However, people born with Down syndrome have a third copy of one chromosome — chromosome 21. Some Down syndrome people have a full copy, whereas others only have partial copies. This explains the varying severity in the manifestation of Down syndrome traits. The more duplicated genetic material there is, the worse the impairments become.
Can Dogs Have Down Syndrome?
If your pooch is showing some of the traits talked about above – such as abnormal facial features or mental retardation – you might be wondering if you have a Down syndrome dog. But can dogs have Down syndrome? Or is this a uniquely human disease? The simple answer here is no, dogs with Down syndrome don’t exist. This is because the genetic makeup of dogs vs humans is completely different. While humans have 23 pairs of chromosomes, dogs have 39 pairs. Down syndrome is diagnosed in people by assessing the number of chromosomes. Anyone with 47 chromosomes in total (23 pairs plus one extra) is considered a Down syndrome person. Therefore, it is impossible to diagnose Down syndrome in dogs. As dogs have 39 pairs of chromosomes, they already have more than the count needed for a Down syndrome diagnosis. The condition is uniquely human and specific to our genetics and chromosome count. As such, it isn’t only dogs that can't have Down syndrome – aside from apes (who have a similar genetic profile to humans) no animals with Down syndrome exist. With that said, dogs can still suffer from genetic disorders that have similar characteristics to Down syndrome in people. If you think you have a Down syndrome dog, your pooch is probably suffering from one of the other congenital conditions instead.
Down Syndrome-Like Genetic Disorders in Dogs
A dog with Down syndrome doesn’t exist, yet other genetic disorders can have Down syndrome-like symptoms. Below are some of the common notable signs that could indicate your dog is suffering from one of these disorders:
- Problems with hearing and eyesight
- Slower than normal rate of growth
- Small stature and shortened limbs
- Poor muscle tone or muscle wasting
- Abnormal, dwarf-like facial features
- A large tongue that hangs out of the mouth
- Cognitive delay and learning difficulties
- Spasms, tremors, and seizures
Multiple genetic diseases all result in some or all of the symptoms listed above. Below are six of the most common congenital diseases in dogs and a brief description of each. Note that genetic disorders such as these are rare! But if your dog is showing signs of mental and physical delays, it is best to be aware of all the conditions that could be responsible.
Congenital Hypothyroidism
Hypothyroidism is an endocrine disorder whereby the body doesn’t produce enough thyroid hormone. This happens for a range of reasons, but congenital hypothyroidism means dogs are born with this condition. The thyroid hormone plays a vital role in metabolism regulation. Therefore, dogs with this disorder have a low metabolic rate. This causes all kinds of physical symptoms that are comparable to what you’d see in a Down syndrome dog.
Pituitary Dwarfism
Also known as growth hormone deficiency, pituitary dwarfism is a condition caused by a below-normal secretion of growth hormone. Growth hormone is produced by the pituitary gland and is responsible for regulating a healthy rate of growth throughout life. With a low amount of this hormone, dogs never reach their fully-grown size and look like puppies for longer. It is most common in German Shepherd breeds and other wolf-type dogs.
Congenital Hydrocephalus
This condition is caused by an excess amount of fluid on the brain. It’s usually diagnosed within the first six months of life, and a puppy with Down Syndrome-like symptoms will be checked for congenital hydrocephalus by a vet. Affected dogs exhibit a slow rate of growth, issues with training, and potential seizures. Small breeds such as Chihuahuas and Toy Poodles seem to have a genetic predisposition for this disorder.
Portosystemic Shunt
Known as PSS for short, a portosystemic shunt is a condition in which blood is passed straight from the intestines to the heart without first visiting the liver. The condition can be acquired, but some dogs are born with this disorder. This happens when there are abnormalities in the formation of the blood vessels connecting these organs. It causes stunted growth, poor muscle tone, and disorientated behavior similar to the symptoms of Down syndrome.
Canine Cognitive Dysfunction
Unlike the other conditions on this list, canine cognitive dysfunction is not a genetic or congenital condition. However, it can still present Down syndrome-like symptoms, including issues with learning and mental confusion. This disorder is common in older dogs and is caused by the natural aging of the brain, similar to Alzheimer’s disease in humans. If you’re dealing with cognitive decline, you’ll only notice strange behavioral symptoms in your dog’s later years.
How to Care for a Special Needs Dog
Caring for a Down syndrome dog is a lot more of a challenge than caring for healthy, genetically normal puppies. If you notice any of the symptoms listed above, your first job is to take your dog to the vet. You need to get any congenital disorders diagnosed as soon as possible so you can determine how to best help your dog. Here are some other tips you can use to make life as easy as possible for your special needs dog:- Regular Vet Checks: You need to visit the vet regularly if your dog has a genetic disorder. This enables your vet to make sure any treatment your dog is on is still working properly. It also means any secondary conditions or complications are picked up early.
- Feed a Healthy Diet: Dogs with Down syndrome-like disorders often suffer from muscle wasting and weakness. Feeding your dog a healthy, balanced diet that is high in protein can help to strengthen these weak muscles as much as possible.
- Dog-Proof Your Home: Dogs with genetic disorders often have issues with sight and hearing, besides mental delays. As such, you can help by dog-proofing your home. Install dog gates, designate a dog-safe area, and limit the movement your dog has around the house.
- Encourage Exercise: As dogs with special needs often have weaker muscles, exercise can help to strengthen their joints. Try engaging your dog in repetitive exercise to help build those muscles back up. You might need non-slip socks or other equipment to help in severe cases.
- Supervise When Possible: Delays in mental development and issues with sight and hearing mean dogs with genetic disorders end up in all kinds of trouble. Always supervise your dog when they aren’t in their “safe space” to keep the risk of accidents low.