Whether You Love Dogs Is Literally In Your DNA

You might have a dog just because you love dogs – but did you ever wonder why you love them?

A new study out of Uppsala University has found that one of the big reasons that dog owners own dogs may literally be found in their blood. Researchers in the United Kingdom and Sweden studied over 35,000 pairs of twins and discovered that people’s propensity to care for canines has a lot more to do with DNA and genetics than we previously thought.

“We were surprised to see that a person’s genetic make-up appears to be a significant influence in whether they own a dog,” said Tove Fall, lead author of the study and a professor at the Department of Medical Sciences at Uppsala University. “These findings have major implications in several different fields related to understanding dog-human interaction throughout history and in modern times. Although dogs and other pets are common household members across the globe, little is known how they impact our daily life and health. Perhaps some people have a higher innate propensity to care for a pet than others.”

The researchers used data from the Swedish Twin registry, which is the largest such registry in the world. Started in the 1960s, it tracks info from tens of thousands of twins, and allows scientists to study genetic matters in ways that we otherwise can’t. Scientists often compare identical twins with non-identical twins – allowing them to contrast two people with the same genes to two people who only share about half their genes.

The study found that more than half of the variance regarding dog ownership was due to genetics – that is, that whether or not you own a pup has a lot to do with who you are when you’re born, and much less to do with your environment.

“These kind of twin studies cannot tell us exactly which genes are involved, but at least demonstrate for the first time that genetics and environment play about equal roles in determining dog ownership,” said Patrik Magnusson, senior author of the study and professor in Epidemiology at Karolinska Insitutet and Head of the Swedish Twin Registry. “The next obvious step is to try to identify which genetic variants affect this choice and how they relate to personality traits and other factors such as allergy.”

What can we learn from the study? Researchers hope we can better understand why we domesticated dogs about 15,000 years ago, as well as how dogs help us today and why we continue to make them part of our homes and families.

“The study has major implications for understanding the deep and enigmatic history of dog domestication” said study co-author Keith Dobney, a Human Palaeoecology professor at the University of Liverpool. “Decades of archaeological research have helped us construct a better picture of where and when dogs entered into the human world, but modern and ancient genetic data are now allowing us to directly explore why and how?”

There’s also a slight downer related to the study: it might explain why other studies have found that dog owners are healthier. In other words, you might simply be healthier not only because dogs keep you active or create a loving environment, but simply because dog owners are genetically healthier than other people.

“These findings are important as they suggest that supposed health benefits of owning a dog reported in some studies may be partly explained by different genetics of the people studied,” said co-other Carri Westgarth, aHuman-Animal interaction professor at the University of Liverpool.

All in all, it’s a combination of environmental factors (like living somewhere with a yard) and genetic factors that result in people adopting pets, but how your ancestors felt about doggos has more to do with your pet ownership than we every thought.