Owning a Dog is in Your Genes

Dogs were the first domesticated animal and have had a close relationship with humans for at least 15,000 years. Today, dogs are even considered to increase the health and wellbeing of their owners. In a new study published today in Scientific Reports, scientists investigated the heritability of owning a dog. Using information from 35,035 twin pairs from the Swedish Twin Registry, they showed that genetic variation explains more than half of the variation in dog ownership.

“We were surprised to see that a person’s genetic makeup appears to be a significant influence in whether they own a dog,” says first author Tove Fall of Uppsala University. “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.”

“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,” adds coauthor Carri Westgarth of the University of Liverpool.

Studying twins is a well-known method for disentangling the influences of environment and genes on our biology and behavior. Because identical twins share their entire genome, and non-identical twins on average share only half of the genetic variation, comparisons of the within-pair concordance of dog ownership between groups can reveal whether genetics play a role in owning a dog. The researchers found concordance rates of dog ownership to be much larger in identical twins than in non-identical ones—supporting the view that genetics indeed plays a major role in the choice of owning a dog.

“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 senior author Patrik Magnusson of Karolinska Insitutet, Sweden.