Can Dogs Have Down Syndrome? Must-Know Facts
There is no easy answer to this question. It is all in the chromosomes. We know that the information present in the 21st pair of human chromosomes determines the presence of Down syndrome. The human body has 23 pairs of chromosomes, whereas dogs have 38. However, research on dog genes is not nearly as advanced as research on humans.
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What is Down Syndrome?
Congenital Down syndrome is a chromosomal defect that is present at birth. A chromosome 21 copy leads to this condition in humans, which inhibits physical and cognitive development. Other health conditions affecting people with Down syndrome include Alzheimer’s and heart disease.
How do chromosomes work?
A chromosome condenses our DNA molecules to fit inside a cell. Every aspect of our physical existence depends on our chromosomes, from our appearance to the health we are likely to have. Everyone is born with 23 pairs of chromosomes, each parent passes down a copy of each chromosome to us. Chromosome 21 carries a partial or complete third copy in Down Syndrome patients. This extra chromosome behaves in different ways, but a significant percentage attaches itself to another chromosome. The Down syndrome symptoms will significantly depend on the chromosome to which the extra chromosome attaches. Research further shows that the most common variation of the syndrome is when one parent passes two copies of chromosome 21 and only one from the other parent.
Why do some dogs show signs of Down syndrome?
It is important to remember that veterinary genetics is constantly developing. We do not yet understand canine genetics as clearly as the human genome, even though veterinary geneticists have extensively studied the canine genome and discovered more than 300 genetic diseases. Although Down syndrome is known to exist in humans, the same cannot be said for dogs due to the lack of scientific evidence.
Interestingly, certain canine health conditions mimic Down syndrome. Among them are:
Congenital Heart Disease: It’s unknown exactly how gene mutations cause congenital heart disease; genetics and environment may also be involved. Affected dogs may experience different symptoms depending on the defect.
Pituitary dwarfism: A lack of growth hormones causes this autosomal disorder. Pituitary dwarf dogs suffer from a range of health problems, such as kidney failure as well as a small stature. Typically, this condition affects German Shepherds and some wolf hybrids.
Hypothyroidism: Although rare, inherited traits may cause dogs to suffer from this condition. Down Syndrome-like symptoms can occur related to metabolism, function, and organ formation.
What are the similarities of Down Syndrome in dogs and humans?
Chromosomal conditions can affect dogs like humans, some symptoms are Down syndrome-like. Examples are listed below.
- Having a smaller head or face than average
- Deficiencies in mental and muscular development
- Hearing or vision problems
- Short legs or other physical deformities
What are the differences between Down Syndrome in dogs and humans?
The primary difference is the number of chromosome pairs in dogs and humans. Canines have 38 chromosome pairs, and humans have 23 pairs. Thus, chromosome 21 contains different genes in dogs and serves other purposes. Moreover, dogs are thought to have fewer chromosomal conditions.
In general, people with Down syndrome have a good quality of life. Chromosomally abnormal dogs are typically unable to find the same happiness as normal dogs. Tragically, many puppies born with such conditions die before birth or soon after. Malformed organs can additionally cause pain in those who survive, and chromosomal disorders may make some dogs unable to eat.
What should you do if you notice Down syndrome-like symptoms in your dog?
A chromosomal abnormality can be difficult to diagnose because genetic testing usually is only available at specialized facilities. Chromosome abnormalities occur at birth, so there is no cure. Let your veterinarian know if you notice any clinical signs. After that, your vet will examine your dog to see if it has any special needs. Treatment is often palliative, which is used to reduce pain and improve the dog’s quality of life rather than cure the condition. The best dog parents can do in such sad circumstances is to follow their vet’s instructions carefully.