A team of Swedish and British scientists has studied the heritability of dog ownership using information from 35,035 twins. The new study suggests that genetic variation explains more than half of the variation in dog ownership, implying that dog adoption is heavily influenced by a human's genetic makeup.
Dogs were the first domesticated animal and had a close relationship with humans for at least 15,000 years. Today, in our society, dogs are common pets and are considered to enhance the well-being and health of their owners. The team compared the genetic makeup of twins (using the Swedish Twin Registry — the largest of its kind in the world) to dog ownership. The goal was to determine whether dog ownership has a hereditary component.
“We were surprised to see that a person's genetic makeup appears to have a significant impact on dog ownership. Thus, these findings have important implications in several areas related to understanding dog-human interaction throughout history and modern times. Although dogs and other pets are members of the household around the world, little is known about how they affect our daily lives and health. Perhaps some people have a higher innate propensity to care for a pet than others.” says the study's lead author.
“These findings are important because they suggest that the hypothesized health benefits of owning a dog reported in some studies may be explained in part by differing genetics of the people studied.”
Studying twins is a well-known method of disentangling the influences of environment and genes on our biology and behavior. Because identical twins share their entire genome, and non-identical twins share only half the genetic variation on average, comparisons of the within-pair concordance of dog ownership between groups can reveal whether genetics plays a role in dog ownership. The researchers found that concordance rates of dog ownership were much greater in identical twins than in non-identical twins — supporting the idea that genetics indeed play a large role in choosing to own a dog.
