Many dog ​​breeds are known for their personalities and behaviors, from the distinctive sounds of huskies to the herding nature of border collies. People have worked to identify genes associated with many of these behaviors, taking advantage of the fact that dogs can interbreed. But this poses its own experimental problems, since it can be difficult to separate some behaviors from physical traits that are characteristic of a given breed: Small breed dogs may appear more aggressive simply because they are more likely to feel threatened.
To get around this problem, a team of researchers recently conducted the largest study of gene-behavior associations within a single dog breed. Using a population of more than 1,000 golden retrievers, they discovered a number of genes associated with behavior within the breed. A high percentage of these genes turned out to correspond to regions of the human genome that are also associated with behavioral differences. But in many cases, these associations were associated with completely different behaviors.
Went to the dogs
The work, carried out by a team based primarily at the University of Cambridge, used the Golden Retriever Lifespan Study, which involved more than 3,000 owners of the dogs completing annual surveys that included information about their dog's behavior. More than 1,000 of these owners also took and submitted blood samples from their dogs; the researchers used these samples to scan the genomes of dogs for variants. These were then compared to ratings of dogs' behavior on a range of issues, such as fear or aggression directed at strangers or other dogs.
Using this data, the researchers determined when different regions of the genome were frequently associated with certain variants. A total of 14 behavioral trends were examined, 12 genomic regions were associated with specific behaviors, and another nine showed slightly weaker associations. It was hard to find much for many of these traits because Golden Retrievers are notoriously friendly and easy-going dogs, so they tended to score low on traits like aggression and fear.
This result was significant because some of these same genomic regions were associated with very different behavior in mixed-breed populations. For example, in a non-breed-specific study, two different areas associated with sensory sensitivity in golden retrievers were associated with love of the chase and owner-directed aggression. This finding suggests that studies have identified genes that may be involved in creating the conditions for behavior but have been targeted for specific outcomes by other genetic or environmental factors.
