The team compared the genetic makeup of 35,035 pairs of twins, using data from the Swedish Twin Registry. As a refresher, identical twins share genes, while fraternal twins share half of their genes. This is how the scientists were able to compare how their choice had been affected by their environment vs their genetics.
They established two key factors:
- If one identical twin owns a dog, their sibling is also more likely to.
- If one fraternal twin owns a dog, their sibling is less likely to own a dog.
The lead author of the study said the team were “surprised to see that a person’s genetic makeup 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 through history and modern times.”
And while it wasn’t determined exactly which genes affect determine which pet a person is likely to pick, it does prove that it's beyond our control.