Do Genetics Determine a Dog's Personality?

It’s an age-old question: is personality determined by nature or by nurture? With nature, genes are the determining factor; whereas with nurture, personality is determined by environment and personal experience. With dogs, as with people, both factors come into play. However, genetics do play a large part in determining a dog’s temperament and personality.

Although the terms “temperament” and “personality” are often used interchangeably, temperament is really only part of what makes up the overall personality of a dog. Temperament is a dog’s natural disposition, which is largely determined by his genetic makeup. Specific dog breeds have certain genetic temperament traits that are passed from generation to generation, just as they have certain physical traits.

Although genetic temperament plays a big part in determining a dog’s personality, it’s not the only factor. Personality is the overall combination of temperament, experience and environmental influences that make your dog unique. How a dog is treated, especially in the first few months of life, is also a big determining factor. For example, regardless of breed temperament, a dog who is raised by his mother, properly weaned and socialized will be much more easy-going, trusting and stable than a dog who’s been kept in a cage from a very young age.

Dog breeds are created -- as they have been throughout history -- by selecting for certain physical and temperament traits. Subsequent generations are bred for these same traits until undesirable traits are bred out, genetic variability is reduced and the dogs “breed true” -- that is, puppies from any male or female of the same breed will possess the desirable traits. Crossing different breeds, as is often done with designer dogs such as labradoodles and cockapoos, can have the effect of balancing out any extreme temperament traits in either parent breed, creating dogs that are more balanced and even-keeled than their purebred parents. However, subsequent generations of cross-bred dogs -- in other words, breeding two labradoodles together -- can bring back the more extreme temperament traits of the original breeds in unpredictable combinations.

Dogs, like people, are much more than just a bundle of pre-programmed genes. Although dog breeds in general have certain temperament traits that make their personalities somewhat predictable, which can be useful in selecting the right breed for your home, individual dogs have unique combinations of temperament and experience that make it impossible to predict how their personalities will manifest. No two dogs’ personalities are exactly alike -- not even purebred dogs from the same litter. Mixed-breed dogs are even more unpredictable, especially those made up of multiple breeds. For this reason, when considering adding a dog to your family, it is useful to know as much about his personal history as you know about his breed.