Border collies are considered exceptionally smart, pit bull terriers are exceptionally aggressive and golden retrievers are particularly fond of children. But how much does the breed actually say about the character of a dog? A study now shows less than expected. The analysis is based on genetic analyzes of over 2,000 dogs of different breeds, combined with surveys of owners on their dogs’ behavior. Accordingly, while genetics play a key role in determining a dog’s appearance, it has little impact on its personality traits.
Which dog breeds are particularly suitable for families? Which are more fearful or aggressive and which are easy to train? Many future dog owners ask themselves such questions when looking for their dream dog – and with just a short search on the Internet they find detailed descriptions of the typical traits of different breeds. Legal regulations are also based on allegedly typical characteristics of certain breeds. So-called fighting dog breeds are subject to a muzzle requirement in many places or may not be kept at all. But what about such racial stereotypes?
Interviews and genetic analysis
A team led by Kathleen Morrill from the University of Massachusetts has now dealt with this question. To do this, the researchers asked 18,385 American dog owners about the characteristics and behavior of their four-legged friends. More than 100 questions dealt with, among other things, how human-related the dog is, how social it behaves towards other dogs, how busy it is with dog toys and how easily it can be disturbed.
The researchers compared the answers to these questions with the information provided by the owner about the breed of their dog. On the other hand, they sequenced the DNA of 2,155 dogs from the sample and analyzed the genome for gene loci and variants that are associated with certain behaviors. They then compared whether and to what extent these gene variants were found in different pedigree dogs and mixed breeds. Around half of the dogs examined were purebred representatives of one of 78 breeds, and the other half were mixed breeds.
Behavior not genetically determined
The result: “Race explains only about nine percent of the behavioral variations and thus has only a low predictive value for individuals,” write the researchers. One of the traits most closely related to breed is how well a dog responds to human commands and how easy it is to train and train. Anxiety and aggression, on the other hand, are hardly related to genetic traits, according to the analysis, but rather seem to be influenced by a dog’s individual experiences in its environment.
The researchers found a significant association with behavior for eleven genetic variants. A certain point in the genome influences how open the dog is towards people it knows and does not know, another determines its tendency to howl. Comparable regions in the human genome have been linked to long-term memory and language, respectively.
Breeds bred for looks
However, these genetic variations have been around for much longer than modern dog breeds, the researchers point out. “Most of the behaviors that we consider to be characteristics of specific modern dog breeds most likely arose over thousands of years of evolution from the wolf to the wild dog to the domesticated dog and finally to the modern dog breeds,” says Morill’s colleague Elinor Karlsson. “These inheritable traits predate our concept of modern dog breeds by thousands of years.”
Modern breed breeding, on the other hand, only began in the 19th century. The focus was less on the character of the dogs than on external features such as body size and the length and pattern of the coat. In fact, according to the analysis, these characteristics are much more firmly anchored in the breed-typical genetics. So if you buy a Golden Retriever, you can be pretty sure that it will look like a typical Golden Retriever. This is less true for behavior: “Race can affect the likelihood of a certain behavior occurring, but contrary to popular belief, it is not meaningful enough to predict an individual’s disposition,” say the researchers.
Source: Kathleen Morrill (University of Massachusetts, USA) et al., Science, doi: 10.1126/science.abk0639