Dog Genetics: Nutrigenomics and the Power of Epigenetics
Ask any pet parent of a mystery mutt what breeds they think make up their best friend, and they will enthusiastically share their best guesses with you. In fact, the International Association of Animal Behavior Consultants (IAABC) has a website where dog enthusiasts can put their knowledge of dog genetics to the test and try their hand at guessing dog breed combinations. Whether you're curious about your dog's ancestry or want to learn more ways to keep him healthy, dog geneticists are unlocking the answers to your questions.
Canine DNA Research
If you had your dog's genetic code mapped, what are all the things you could learn from dog DNA? Fortunately, science is already hard at work studying dog genetics and learning new ways to help our furry friends be even healthier.
Nowadays, you can easily have your dog's DNA tested by your veterinarian to see what dog breeds make up his family tree. Most vets will not have this capability in the clinic, but rather send their samples out to a lab to provide the results. There are also at-home kits that you can do and have the test analyzed by geneticists in a lab. Scientists study dog genetics the same way they study human DNA: by running a sample taken from a swab of a dog's cheek through a machine that maps the genetic code and looking for telltale markers. Depending on the genetic testing lab your vet uses, you will receive a report of your pup's possible breed ancestry or other health information.
Genetics and Health
Genetics can tell us lots of things about our dogs. Finding out that your pup is part greyhound and part Doberman is just the tip of the iceberg. The genetic code also gives us valuable information about potential personality traits, genetic disease tendencies, how big your puppy might get, and if shedding is in your future.
While we know it isn't the only factor, dog DNA can also help predict whether a dog will develop certain health problems. Dog genetics can reveal whether a dog has genetic mutations that can result in disease, and that knowledge can empower pet parents to take preventive steps to minimize the potential impact. For example, MDR1 is a gene with a mutation contained within it that increases a dog's sensitivity to medication. Dogs with an MDR1 mutation can have serious adverse reactions to drugs. Having your dog tested for the MDR1 gene mutation could arm you with the knowledge to save him from adverse reactions, writes the Washington State University Veterinary Clinical Pharmacology Laboratory.
Inheritance and Environment
An easy way to understand dog DNA is to think of it as a blueprint for your dog's body, predicting not only physical traits but behavioral ones as well. Historically speaking, most people believed that genes dictated an unavoidable future — if you had a genetic marker for disease, then you would get that disease. What we now know, however, is that even if a blueprint codes for a condition, that doesn't necessarily mean that your dog will develop that condition.
In other words, your dog's DNA does not dictate his destiny. Discover magazine explains that the reason for this is a network of other factors, called epigenetics, that influences how genes behave and express (turn on and off) without changing their physical makeup. Epigenetics encompasses both inherited expression factors and environmental influences.
The Power of Epigenetics
Scientists now understand that environmental factors such as stress, infection, nutrition, and exercise are more important than previously thought in controlling what genes are expressed. Additionally, your pet's microbiome, tiny microbes living in and on your pet, are much more important than previously thought and are just now starting to be understood. In humans, these factors can even impact future generations. A Swedish study in the European Journal of Human Genetics found that the grandsons of men who lived during a period of plentiful food as children were more likely to develop diabetes and heart disease from overeating!
Like humans, a dog's individual lifestyle and environment directly interact with their DNA to influence either positive or negative epigenetic changes. Even if your dog has the perfect genetic blueprint, factors that influence epigenetics, such as a sedentary lifestyle or poor nutrition can erode the foundation of his health. Conversely, keeping your pup as healthy as possible might help lower his risk of developing a problem his breed is predisposed to.
Nutrigenomics: Nutrition + Genetics
The old adage holds true for us and our pets: you are what you eat. Nutrition is a powerful driver of epigenetic modifications that influences your dog's DNA. Different ingredients and nutrients have the ability to influence a gene's activity or expression, and can even change how genetic disease manifests. The study of the effect of nutrition on the genome is known as nutrigenomics. Current science can't provide your vet with a magic formula for good health, but it's an exciting new frontier in preventive medicine for our pets.
How can you benefit your dog's genetic health? Do what you can to positively influence epigenetic factors: reduce your dog's stress, give him plenty of exercise and feed him healthy food. Choosing healthy, research-based pet food that has been comprehensively studied and proven to benefit your dog's biology is a great first step. You may not be able to change his inherited blueprint, but a little knowledge of genetics can help you keep your dog happy and healthy.
Dr. Sarah Wooten
Dr. Sarah Wooten graduated from UC Davis School of Veterinary Medicine in 2002. A member of the American Society of Veterinary Journalists, Dr. Wooten divides her professional time between small animal practice in Greeley, Colorado, public speaking on associate issues, leadership, and client communication, and writing. She enjoys camping with her family, skiing, SCUBA, and participating in triathlons.