Genetic testing of dogs predicts problem behaviors in clinical and nonclinical samples

Abstract

Background Very little is known about the etiology of personality and psychiatric disorders. Because the core neurobiology of many such traits is evolutionarily conserved, dogs present a powerful model. We previously reported genome scans of breed averages of ten traits related to fear, anxiety, aggression and social behavior in multiple cohorts of pedigree dogs. As a second phase of that discovery, here we tested the ability of markers at 13 of those loci to predict canine behavior in a community sample of 397 pedigree and mixed-breed dogs with individual-level genotype and phenotype data. Results We found support for all markers and loci. By including 122 dogs with veterinary behavioral diagnoses in our cohort, we were able to identify eight loci associated with those diagnoses. Logistic regression models showed subsets of those loci could predict behavioral diagnoses. We corroborated our previous findings that small body size is associated with many problem behaviors and large body size is associated with increased trainability. Children in the home were associated with anxiety traits; illness and other animals in the home with coprophagia; working-dog status with increased energy and separation-related problems; and competitive dogs with increased aggression directed at familiar dogs, but reduced fear directed at humans and unfamiliar dogs. Compared to other dogs, Pit Bull-type dogs were not defined by a set of our markers and were not more aggressive; but they were strongly associated with pulling on the leash. Using severity-threshold models, Pit Bull-type dogs showed reduced risk of owner-directed aggression (75th quantile) and increased risk of dog-directed fear (95th quantile). Conclusions Our association analysis in a community sample of pedigree and mixed-breed dogs supports the interbreed mapping. The modeling shows some markers are predictive of behavioral diagnoses. Our findings have broad utility, including for clinical and breeding purposes, but we caution that thorough understanding is necessary for their interpretation and use.

Differences in small-breed dogs' body language and vocalizations in a negative context

“…Various studies have been conducted on behavioral problems in dogs of different sizes, and they have found that small dogs with similar genetic markers and brain sizes tend to exhibit more behavioral disorders. (22,24) Previous research has classified these breeds as belonging to similar categories and possessing similar behavioral repertoires. For instance, Chihuahua and Poodle have been identified as non-working dogs that exhibit higher levels of direct social fear, as assessed by the C-BARK.…”

“…(20) In general, a dog's body size can predict variations in its behavioral traits, such as aggression, anxiety, and trainability. (21,22) For example, small breeds tend to exhibit behavioral issues more frequently, (23) whereas larger breeds display a greater inclination towards training. (22,24) Another source of variation in behavior and body language between dogs is the sex and age of the individual.…”

“…(21,22) For example, small breeds tend to exhibit behavioral issues more frequently, (23) whereas larger breeds display a greater inclination towards training. (22,24) Another source of variation in behavior and body language between dogs is the sex and age of the individual. A review reported that, in general, male dogs tend to be more aggressive and bolder but show more social contact with humans than female dogs during human-dog play.…”

Comparison of behavioural tendencies between “dangerous dogs” and other domestic dog breeds – Evolutionary context and practical implications

“…For example, strong positive correlation was found between all the components of C‐BARQ questionnaire (Hsu & Serpell, 2003) related to aggression and fear (stranger‐, owner‐, dog‐ and familiar dog‐directed aggression, stranger‐directed, dog‐directed and non‐social fear) and veterinary behavioural diagnoses in 122 dogs (Zapata et al, 2022). Moreover, several genetic loci have been shown to have a significant association with these behavioural traits (Zapata et al, 2016) and could correctly predict individual behaviour in a cohort of nearly 400 pure‐ and mixed‐breed dogs, while a subset of those loci could predict veterinary behavioural diagnoses (Zapata et al, 2022). This demonstrates that owner‐assessed behavioural traits can have a strong genetic component and may serve as good predictors of individual behavioural problems.…”

An artificial intelligence approach to predicting personality types in dogs

“…The instrument’s various scales have been shown to have adequate internal reliability and acceptable test-retest and inter-rater reliability 22 – 24 . Construct and criterion validity of the C-BARQ have been established by demonstrating associations with: (a) clinical diagnoses of behavior problems in companion dogs 19 , (b) training outcomes in working dogs 15 , 22 , 25 , (c) the behavior of dogs in standardized test batteries 16 , 26 – 31 , (d) neurophysiological markers of canine anxiety disorders 32 , 33 , and (e) genetic loci known to be associated with the brain and behavior 34 – 36 .…”