Dog ownership is influenced by hereditary factors

Published: 2019-05-20


According to a new study, co-led by Tove Fall (SciLifeLab/Uppsala University), your genetic make-up greatly influence your decision to own a dog. By studying data from 35 035 twin pairs from the Swedish Twin Registry, the researchers observed that it was far more common for identical twin siblings to both own a dog than non-identical twin siblings. In fact, genes seem to account for more than half of the difference in dog ownership while the rest is thought to be based on environmental factors.

Since the domestication of dogs more than 15 000 years ago, dogs and humans have been living close together. They now play an important roll in our society and are believed to increase the well-being and health of their owners. To determine if the decision to own a dog is influenced by heritable factors the researchers compared the genetic make-up of identical and non-identical twin pairs.

“We were surprised to see that a person’s genetic make-up appears to be a significant influence in whether they own a dog. As such, 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,” says Tove Fall, lead author of the study, in a press release from Uppsala University.

Carri Westgarth, Lecturer in Human-Animal Interaction at the University of Liverpool and co-author of the study, adds: “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”.

Twin registries are excellent resources when trying to distinguish between genetic and environmental influence.  This is because identical twins share their entire genome while non-identical twins only share half. The researchers found that both siblings in identical twin pairs was much more likely to own dogs than siblings in non-identical twin pairs, supporting the theory that hereditary factors play an important role.

“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. 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”, says Patrik Magnusson, senior author of the study and Associate Professor at Karolinska Insitutet and Head of the Swedish Twin Registry.

“The study has major implications for understanding the deep and enigmatic history of dog domestication. 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?”, says zooarchaeologist and co-author of the study Keith Dobney, Chair of Human Palaeoecology at the University of Liverpool.