The Human Genome Project sequenced human DNA for the first time in 2003. Not long afterward, the genome of a Boxer named Tasha was sequenced in 2004 and the genome of an Abyssinian cat named Cinnamon was sequenced in 2007. Since then, research into dog and cat genetics has advanced rapidly. Approximately 900 hereditary diseases or genetic predispositions have been identified in dogs and 200 in cats¹. DNA tests are giving us deeper insights into health and the risks our pets face. They allow us to be more informed and proactive in their care. Let's learn more about this incredible advancement in pet science.

How DNA Testing Is Making Pets Healthier

Over the years, testing of our pets' DNA has become more routine and more accurate. For example, studies in dogs and cats have identified more breeds at risk of genetic disorders as well as how these risks compare to purebred vs. mixed breed dogs¹. Many breeding associations and the World Small Animal Veterinary Association recommend using genetic tests to help reduce how often genetic diseases occur in pets².

All of this information can be used to ensure that breeding pairs are healthy and decrease the likelihood of genetic issues of purebred puppies or kittens. It can inform your veterinarian of your pet's risk factors for various disorders and you can be more aware of potential health issues as you make decisions for your pet. It's also fun to learn about the breeds that make up our mixed-breed pets and their characteristics.

What Is the Pet DNA Testing Process Like?

After you choose a company to work with, you purchase a test kit to be sent to your home or your veterinarian's office. Many kits require swabbing your pet's oral cavity for a DNA sample, which you may do at home. Some DNA tests require your pet's blood sample, which should be performed at your vet's office. It's very important to follow the kit's collection instructions carefully. Contact the company if you have any questions about the collection process before you start. A mistake when you collect or send the sample can affect your pet's results.

Once you have collected the sample, you return it in the recommended packaging. From that sample, the lab purifies your pet's DNA and performs a battery of post-processing procedures to run the genetic testing.

DNA testing takes time – most results will take four to six weeks. Depending on the company, the results may arrive online, in the mail, or go directly to your veterinarian.

Types of Pet DNA Tests and Their Benefits

Whether you want to know if your pet is genetically predisposed to any conditions or are curious about what your mixed breed is made of, DNA tests provide useful results.

Breed Mix

Many companies provide a breakdown of your pet's breed mix based on their DNA. Some companies even provide information on each of the breeds, such as origins, behavioral characteristics, and physical attributes, so you can learn more about them. It is important to note, however, that genetic similarity to a specific breed does not always equal ancestry. For example, your cat may show high genomic similarity to Persians either because it has a Persian cat in its family tree (i.e., it is directly descended from a Persian cat), or because your cat and the Persian breed shared a common ancestor at some point in time. Conflating identity by state with identity by descent is a common misconception in the field.

Inherited Disorders

Some pets may carry genetic markers associated with a disease that can be detected through DNA analysis. Many companies provide pet owners and breeders with information on whether an animal is at risk for genetic disorders. Some may run panels specific to certain breeds based on the disorders common to those breeds. Other companies may run panels screening for most known genetic markers associated with health conditions affecting cats or dogs, to better serve mixed breed pets.

The results presentation will vary from test to test, but will likely include something similar to the following categories:

• Negative or clear. Your pet does not have the genetic mutations associated with this disorder. Please note that this does not mean that your pet will never develop the disease in question. Yet unknown genetic factors, as well as lifestyle and environment, can also influence disease risk.
• Carrier. Your pet may pass the genetic mutation associated with the disorder to its offspring. However, the tested animal itself is unlikely to develop the disease.
• At risk. Your pet has a genetic mutation associated with a polygenic disease (where more than one genes are implicated) or one associated with a disease where the severity may vary depending on the number of mutated gene copies inherited from the parent.
• High risk. Your pet has a genetic mutation associated with a condition where even a single copy of the mutation is highly likely to result in developing the disease.

DNA Testing for Breeders

Breeders of dogs and cats may use DNA testing to verify the parents of puppies or kittens (called parentage testing), to guide them in selecting coat colors or, most often, to guide in the prevention of inherited disorders common to the breed. This can also help prevent breeding along family lines to promote genetic diversity. This testing is available through their kennel club, the Cat Fancier's Association, or the Governing Council of the Cat Fancy in the UK. It is also available for purchase directly from the DNA tests vendors.

Microbiome Tests

The microbiome is the assortment of bacteria, fungi, and viruses that live in a specific area (e.g., soil, a mountain spring, different regions of the body - gut, skin, etc.) Each area of the body has its own microbial composition. Different disease states are sometimes associated with changes to the microbiome. These changes may be either causative or simply a readout of disease-associated mechanisms that may influence the microbiome as a byproduct. Either way, investigating the state of the microbiome can point towards signs of disease and there are commercially available tests that do that.

There are various tests that fall into this category:

• Oral health DNA tests. These examine the microbial composition of your pet’s mouth. You collect a sample at home from your pet's mouth and receive a report on their oral microbiome. The report may indicate an imbalance or a level of risk for different dental diseases.
• Gastrointestinal health DNA tests. These tests examine fecal samples to assess the intestinal microbiome. The report will list the types of fecal bacteria found and likely their respective abundance. When the pet’s gut microbial composition deviates from that of the average healthy pet, this state is known as dysbiosis, an imbalance of intestinal bacteria that can be associated with such signs as weight loss, diarrhea, decreased appetite, and weight loss.

What Should You Do with Your Pet's DNA Results?

If you have a mixed breed pet, the new knowledge about your pet's breeds can help explain their behavioral traits and determine the next steps in training and understanding your pet. This is especially true for dogs because specific breeds are often bred to have very clear traits. For example, if your dog is a herding breed mix, they may need a lot of exercise and mental stimulation.

The results of any health DNA test should be discussed with your veterinarian. The oral health DNA test results may allow you and your vet to develop the best dental care plan for your pet. The gastrointestinal DNA test results may diagnose dysbiosis and help your veterinarian develop a treatment plan.

If your pet's report states that your pet is at risk for an inherited disorder, keep in mind that risk is not a guarantee that your pet will become sick. However, if that is the case, you and your veterinarian can establish a plan to ensure your pet has the best possible care.