Is Your Dog’s Anxiety Genetic? Unraveling the Hereditary Factors That Influence Canine Anxiety

Introduction

If you’ve ever watched your dog pace nervously before a thunderstorm, destroy pillows when left alone, or cower at the sight of a stranger, you’ve encountered the baffling and sometimes heartbreaking world of canine anxiety. The furrowed brows and tucked tails we see in our four-legged companions are not so different from our own feelings of unease and distress. But have you ever stopped to wonder, “Is my dog’s disposition to anxiety written in their genes?”

Welcome to a subject as intricate as the genome itself: the role of genetics in canine anxiety. For those among us who are clinicians, scholars, or just plain dog lovers, understanding the genetic component of canine anxiety isn’t just a matter of curiosity—it’s essential. Why? Because if we can pinpoint a genetic predisposition, we open up a whole new avenue for early intervention, targeted treatment, and ultimately, a better quality of life for dogs.

In this comprehensive article, we’ll explore the fascinating intersection of genetics and mental health in dogs. We’ll dive into what current science says about the genes that could be pulling the strings behind the scenes of your dog’s behavior. Along the way, we’ll take a close look at the types of canine anxieties that might have genetic links, investigate the emerging field of epigenetics, and discuss why knowing your dog’s lineage could be more than a matter of pedigree—it could be a roadmap to a happier, less anxious life for your beloved pet.

So, fasten your seat belts—whether you’re a dog owner, a seasoned veterinarian, or someone with a keen interest in animal behavior, you’re in for an informative ride!

The Genetic Basis of Canine Behavior

The Dog Genome

Ah, the canine genome, a wonderland of genetic intricacies! Comprising roughly 2.4 billion base pairs and approximately 19,000 protein-coding genes, the canine genome is a wellspring of information that holds the secret to many aspects of a dog’s physiology and behavior (Ostrander et al., 2017). It’s like the ultimate instruction manual, except instead of guiding the construction of a piece of furniture, it outlines the biological and behavioral traits of Man’s Best Friend.

While the sequencing of the human genome was a colossal feat, let’s not forget the landmark accomplishment in the field of canine science—the complete sequencing of the dog genome, published back in 2005. This was a milestone that provided researchers with unprecedented insights into not only inherited diseases but also complex behaviors in dogs (Ostrander et al., 2017).

So how is this accomplished? Traditionally, genome sequencing involved laborious and expensive techniques, but advances in technology have now made it faster and more affordable. More importantly, these advances have made it feasible to study the genetic underpinnings of complex traits like behavior. The focus has shifted from merely identifying individual genes linked to specific diseases to understanding how a constellation of genes could interact with the environment to elicit a complex behavior like anxiety (Ostrander et al., 2017).

By studying the canine genome, researchers have managed to identify certain genes that have been linked to behavioral traits, including various forms of anxiety. Understanding these genes not only offers scientific insights but also holds real-world implications for the treatment and even prevention of anxiety disorders in dogs. Imagine being able to offer a dog owner the chance to not just manage but potentially prevent the crippling anxiety that limits their pet’s life. That’s the promise held by the ongoing study of the dog genome.

Behavioral Genetics

Behavioral genetics is a captivating interplay between the fields of psychology and genetics, offering profound insights into how inherited traits influence behavior (MacLean & Hare, 2018). This interdisciplinary approach goes beyond the surface to unravel the age-old conundrum of “nature vs. nurture,” shedding light on the extent to which genetic predisposition and environmental factors contribute to behaviors, including anxiety in dogs (MacLean & Hare, 2018).

In the context of canines, understanding behavioral genetics is akin to having a genetic blueprint for individual predispositions, including those related to anxiety (MacLean & Hare, 2018). For instance, the knowledge that a particular breed is genetically inclined towards separation anxiety could facilitate early interventions like desensitization and counterconditioning, providing a proactive pathway to management.

Research methods in canine behavioral genetics range from observational studies to more complex genome-wide association studies (GWAS). A pioneering study by MacLean and Hare (2018) utilized cognitive measures to inform selections for service dogs, emphasizing that genetic predispositions extend beyond physical traits to behavioral inclinations, such as the ability to remain calm in stressful situations.

The application of behavioral genetics has the potential to revolutionize our understanding of canine behavior. It presents the exciting prospect of personalized dog training and treatments, and even the ability to predict certain behavioral outcomes. This is invaluable for clinicians and dog owners alike, offering a more precise and proactive approach to managing and possibly even preventing behavioral issues, including anxiety (MacLean & Hare, 2018).

Identifying Anxiety-linked Genes

Diving deeper into the genetic architecture of canine anxiety, certain genes have come under the spotlight for their potential roles in modulating anxious behaviors. Among the most studied is the serotonin transporter gene, which plays a critical role in regulating mood and emotional stability in both humans and dogs (Overall, 2013).

Serotonin, often referred to as the “feel-good hormone,” is key in moderating mood and emotional states. The serotonin transporter gene is involved in the reuptake of serotonin in neural synapses, effectively regulating the levels of this neurotransmitter in the brain. Alterations or mutations in this gene can lead to imbalances in serotonin levels, which are often correlated with symptoms of anxiety (Overall, 2013).

Research spearheaded by Overall (2013) suggests that variations in the serotonin transporter gene could be linked to a range of anxiety behaviors in dogs, from generalized anxiety disorders to more specific phobias and compulsions. This revelation holds tremendous promise for targeted treatments; if we know the genetic culprit, we can potentially tailor medications and behavioral interventions to target this gene specifically.

But it’s not just about serotonin or a single gene. The landscape of genes influencing canine anxiety is complex and multifactorial. Other neurotransmitter systems, such as dopamine and norepinephrine, also come into play, each with their own corresponding genes (Overall, 2013). Understanding this intricate network is akin to solving a complex puzzle, with each piece offering a new insight into the multifaceted nature of canine anxiety.

So, what does this mean for you, the dog owner, or for clinicians and researchers? It means a future where behavioral issues can be treated at their genetic roots. It signifies the advent of personalized medicine for dogs, where genetic profiling could pave the way for more effective, targeted treatments, thus offering our canine companions a better quality of life (Overall, 2013).

Types of Anxiety Disorders and Corresponding Genetic Links

Anxiety in dogs is not a one-size-fits-all issue; rather, it manifests in various forms, each with its own set of symptoms and, intriguingly, genetic predispositions. Whether it’s the despondency displayed during a thunderstorm or the heightened distress when left alone, understanding the types of anxiety disorders that afflict dogs can offer a more targeted approach to management and treatment. This section will peel back the layers of different anxiety disorders while connecting the dots to their genetic origins, giving us a comprehensive yet nuanced understanding of the problem.

Separation Anxiety

If you’ve ever returned home to a scene of canine-induced chaos—think shredded cushions, claw marks on the door, or incessant barking—you might be dealing with a classic case of separation anxiety. But have you ever wondered if your dog’s breed might be a factor in this behavior? Indeed, research has shown that some breeds are genetically predisposed to suffer from separation anxiety more than others (Serpell & Duffy, 2016).

In a fascinating study by Serpell and Duffy (2016), certain breeds, such as the Labrador Retriever and the German Shepherd, exhibited a higher frequency of separation anxiety compared to others. These findings hint at a genetic predisposition that goes beyond mere environmental factors. What this translates to is that if you are bringing home a dog from one of these predisposed breeds, being aware of this genetic inclination can help you take proactive steps to mitigate the symptoms.

That said, it’s essential to note that while genetics can play a significant role, it doesn’t absolve the impact of environmental factors. Training, socialization, and even the owner’s behavior can either exacerbate or mitigate the genetic predisposition (Serpell & Duffy, 2016). This is where professionals like you come in—by coupling an understanding of genetic susceptibility with behavioral modification techniques, you can offer a holistic treatment approach.

Moreover, the study brings to light the possibility of screening for genetic markers associated with separation anxiety. In a future where genetic screening becomes more accessible, identifying these markers could lead to early interventions, reducing the emotional toll on both the dogs and their owners (Serpell & Duffy, 2016). 

Noise Anxiety

The startling sound of fireworks, a rumbling thunderstorm, or a sudden loud noise can cause some dogs to spiral into a state of panic. This type of anxiety, known as noise anxiety, is often acute and specifically triggered by loud noises. Research in this area has revealed a genetic component, adding another layer of complexity to the understanding of canine anxiety disorders (Storengen et al., 2014).

A noteworthy study conducted by Storengen and colleagues (2014) investigated the heritability of noise anxiety in dogs. Their findings confirmed a heritable aspect to this form of anxiety, suggesting that a dog’s genetic composition can influence its susceptibility to noise-induced panic. For some breeds, the heritability of noise anxiety was estimated to be between 30-35%.

The implication of these findings is twofold. For breeders and those looking to adopt a dog, knowing about such genetic predispositions can inform their selection process. If a specific breed has a high genetic risk for noise anxiety, proactive measures such as specialized training or environmental modification can be beneficial (Storengen et al., 2014).

For professionals in veterinary medicine and dog behavior consulting, this genetic data can be a cornerstone for innovative treatment methods. There may soon be an avenue for using genetic markers to identify dogs with higher susceptibility to noise anxiety, thereby paving the way for more personalized treatments. Imagine a future where a straightforward genetic test could dictate a customized treatment plan, which could include pharmacotherapy combined with specialized behavioral modification techniques (Storengen et al., 2014).

It’s also crucial to note the emotional and physical toll that noise anxiety can take on dogs, potentially leading to a range of stress-related health issues. By recognizing and addressing a possible genetic root cause, the aim is to improve not only the mental health of the dog but its overall well-being (Storengen et al., 2014).

Social Anxiety

Social interaction is fundamental to the well-being of both humans and animals. However, for some dogs, social scenarios can trigger an undue amount of stress, leading to avoidance behaviors or even aggression. This specific condition, known as social anxiety, can be perplexing to understand and challenging to manage. Emerging research indicates that genetics might play a pivotal role in this type of anxiety as well (van Rooy et al., 2018).

A study led by van Rooy and colleagues (2018) has offered some key insights into the genetic underpinnings of social anxiety in dogs. The researchers found that dogs exhibiting social anxiety had certain genetic markers that were notably different from those in dogs who were more socially confident. This ground-breaking discovery advances the understanding that social anxiety in dogs may not be purely a product of environment or upbringing but could be partially encoded in their DNA.

For those involved in canine breeding or those contemplating adopting a dog, these findings offer valuable information. Understanding that there may be a genetic predisposition for social anxiety can influence the decision-making process. For example, breeds or individual dogs identified as having a genetic predisposition for social anxiety may benefit from early socialization techniques or gradual exposure to social situations to mitigate symptoms (van Rooy et al., 2018).

For professionals in the field, the study provides an evidence-based foundation for the development of targeted interventions. It raises the possibility of genetic screening for markers associated with social anxiety, much like in the case of noise or separation anxieties. The availability of such screening could contribute to more tailored therapeutic strategies that integrate both pharmacological and behavioral interventions (van Rooy et al., 2018).

Furthermore, identifying a genetic basis for social anxiety holds promise for improving the long-term well-being of affected dogs. Just as with other forms of anxiety, social anxiety can lead to a variety of health-related complications. Uncovering its genetic roots offers the opportunity for preemptive action, thus potentially averting the cascade of stress-induced health problems (van Rooy et al., 2018).

The Role of Epigenetics

In the quest to unravel the genetic puzzle of canine anxiety, one can’t overlook the influence of epigenetics. While genetics provide the basic script, epigenetics is akin to a director who can modify that script in real time, affecting how genes are expressed without changing the underlying DNA sequence. Below, we delve into the concept of epigenetics and examine how it interfaces with genetic predispositions to shape behaviors, including anxiety in dogs.

What is Epigenetics?

For many, the term ‘epigenetics’ may evoke a sense of scientific complexity, but at its core, it’s a concept that can be understood in rather straightforward terms. Epigenetics refers to modifications in gene expression that do not involve changes to the underlying DNA sequence (Feil & Fraga, 2012). Imagine the genome as a grand piano; while the keys (genes) remain the same, epigenetics would be the pianist’s style and choice of chords, affecting how the music (gene expression) comes to life.

Feil and Fraga (2012) describe epigenetics as a system that allows for gene regulation influenced by environmental factors. These changes can happen at any stage of life and can be temporary or last a lifetime. Importantly, some epigenetic changes can even be passed on to future generations, meaning that experiences affecting gene expression in one generation could influence traits and behaviors in subsequent generations.

In the context of canine anxiety, understanding epigenetics is crucial for two reasons. First, it provides an additional layer of explanation for why dogs with similar genetic makeups can exhibit different levels of anxiety. Second, it opens up a new frontier for treatment options that could modify gene expression rather than targeting the gene itself.

Epigenetic Factors in Canine Anxiety

While genetics can provide a broad roadmap for understanding behavioral predispositions, it’s the epigenetic factors that add intricate details to this map. These factors can act like a dimmer switch on a light, modulating the expression of genes that are associated with anxiety behaviors. Research is increasingly focused on how these epigenetic changes contribute to variances in anxiety levels among dogs (Kinnally et al., 2018).

One study that stands out in this realm was conducted by Kinnally and colleagues in 2018. Their research focused on identifying specific epigenetic markers related to anxiety behaviors in dogs. While this area of study is still burgeoning, their findings suggested that alterations in DNA methylation, a core mechanism of epigenetic regulation, were significantly associated with symptoms of anxiety.

For professionals in the field, this epigenetic layer adds valuable context when assessing and treating canine anxiety. It offers a theoretical framework for the development of new therapies aimed at modifying these epigenetic markers. Imagine a scenario where veterinarians and behavior consultants could take into account not just the genetic but also the epigenetic profile of a dog when customizing treatment plans. It might involve nutritional interventions, environmental modifications, or targeted pharmacological approaches that can modulate these epigenetic factors (Kinnally et al., 2018).

For dog owners, understanding that a dog’s environment and experiences can alter their genetic expression concerning anxiety has profound implications. It means that proactive measures, such as creating a stable environment or engaging in specific types of training, can potentially induce positive epigenetic changes. These alterations could mitigate the expression of genes linked to anxiety, offering a route for prevention as well as treatment (Kinnally et al., 2018).

By diving into the role of epigenetics, we enrich our understanding of why dogs might suffer from anxiety and how to best address it. It offers a framework for more targeted, flexible treatments, and provides hope that even with a genetic predisposition to anxiety, there may still be effective ways to manage or even mitigate these symptoms (Kinnally et al., 2018).

Importance of Lineage Information 

When it comes to tackling the intricate issue of canine anxiety, knowing your dog’s lineage can be a crucial asset. It adds a layer of understanding that complements genetic and epigenetic data, providing both professionals and pet owners with practical tools for assessing and treating anxiety-related issues. This section will examine why lineage is easier to trace in purebred dogs but will also discuss its importance for mixed breeds.

Purebred vs. Mixed Breed

At first glance, one might assume that lineage information is only useful for purebred dogs, where detailed pedigree records often exist. While it’s true that purebred lineage can provide a wealth of information about potential genetic predispositions, including tendencies towards anxiety (Turcsán et al., 2017), it’s crucial to recognize that understanding lineage is also highly relevant for mixed-breed dogs.

A study by Turcsán and colleagues in 2017 highlighted that even in mixed-breed dogs, certain behavioral traits, including anxiety-related behaviors, could be correlated with specific breeds present in a dog’s lineage. Essentially, knowing a mixed-breed dog’s lineage could provide clues to specific breeds’ traits and behavioral predispositions, including those related to anxiety. For instance, if a mixed-breed dog has a significant percentage of a breed known for separation anxiety, that information could be invaluable in proactive training and treatment approaches.

For dog owners, the accessibility of DNA testing services now makes it possible to gain insights into the breed composition of mixed-breed dogs. These tests can serve as a preliminary step in identifying potential behavioral traits and medical issues related to specific breeds, thus offering a proactive approach to managing anxiety-related symptoms.

In the case of purebreds, lineage information often comes with a detailed history that can include not just medical data but also behavioral traits observed in a dog’s ancestors. For example, if a purebred dog comes from a line where multiple generations have exhibited noise anxiety, that information could be instrumental in developing a targeted desensitization program.

Lineage information, therefore, serves as a complementary tool alongside genetic and epigenetic knowledge. By giving us a fuller picture of a dog’s background, it allows for more precise risk assessment and targeted treatment options for combating anxiety (Turcsán et al., 2017).

Practical Applications for Treatment

Understanding the genetic background of a dog isn’t merely an academic exercise. It has practical, real-world implications, especially when it comes to designing and implementing treatment plans for anxiety disorders. In her seminal work, Dr. Karen Overall makes a compelling argument for the utilization of genetic information in determining both pharmacological and behavioral interventions (Overall, 2013).

Pharmacotherapy

The genetic background can significantly influence a dog’s response to medications. For instance, some breeds are more sensitive to specific types of medication due to their metabolic rates or the presence of certain receptors, which can be identified through genetic markers (Overall, 2013). Having lineage information, particularly for purebred dogs, can aid veterinarians in choosing the right type and dose of medication, thereby reducing the risk of side effects or ineffective treatment.

Moreover, for dogs predisposed to certain types of anxiety, preemptive pharmacological intervention may be considered. For example, if a dog comes from a lineage with a history of severe noise anxiety, medication to mitigate acute stress during thunderstorms or fireworks might be prescribed in advance. 

Behavioral Consulting, Therapy, Coaching

Behavioral therapy is another area where lineage information can be incredibly useful. Specific breeds have particular behavioral tendencies; for example, herding dogs may be more prone to motion-triggered anxieties, while hounds may be more likely to suffer from separation anxiety (Overall, 2013). Knowing these predispositions allows behaviorists and trainers to develop a more targeted behavioral modification plan.

For mixed breeds, if lineage information indicates a dominant percentage of a breed prone to specific anxieties, a targeted behavioral therapy plan can be formulated accordingly. This way, you’re not working from a generic template but are addressing the individual dog’s inherited tendencies.

Combined Approaches

Finally, in many cases, the most effective treatment may involve a combination of pharmacotherapy and behavioral therapy. Here, too, lineage can play a role. For example, a dog with a genetic predisposition towards extreme social anxiety may benefit from a pharmacological approach to reduce immediate symptoms, combined with gradual desensitization and positive reinforcement techniques tailored to their specific breed characteristics (Overall, 2013).

Ethical Considerations in Breeding

As breeders and prospective pet owners become increasingly aware of the role genetics play in canine behavior, ethical questions arise concerning the breeding of dogs known to have a predisposition to anxiety disorders. A study conducted by Oberbauer et al. in 2017 posits that ethical breeding programs should incorporate knowledge of behavioral genetics to reduce the incidence of heritable disorders, including anxiety-related issues.

Breeding for Behavior, Not Just Appearance

Traditional breeding practices have often focused on physical characteristics or abilities, such as size, coat type, or agility. However, as our understanding of canine genetics becomes more nuanced, there’s a growing recognition that breeding for behavioral traits, including mental health aspects like predisposition to anxiety, should be part of ethical breeding programs (Oberbauer et al., 2017).

Informed Consent for Prospective Pet Parents

Ethical breeding also encompasses transparency and informed consent. Breeders should disclose any known genetic predispositions to behavioral issues, including anxiety, to prospective pet owners. Such disclosure allows potential owners to make informed decisions and prepare adequately for the challenges they might face (Oberbauer et al., 2017).

The Role of Genetic Testing

As genetic testing becomes more accessible and accurate, there’s a compelling argument for its use in breeding programs to screen for potential behavioral issues. These tests can identify the markers associated with anxiety disorders, and breeders can use this information to make more ethical choices regarding which dogs to breed.

The Dilemma of Popular but Predisposed Breeds

Certain breeds that are prone to anxiety disorders remain incredibly popular. In these cases, the ethical dilemma deepens. Is it responsible to continue breeding these dogs knowing the likelihood of passing on anxiety-related issues? Some advocate for a balanced approach, where the positive traits of these breeds can be preserved while making concerted efforts to reduce the incidence of anxiety disorders through selective breeding (Oberbauer et al., 2017).

Case Studies

Utilizing case studies provides tangible context to the scientific discussions around genetics and canine anxiety. These examples offer concrete illustrations of how understanding a dog’s genetic makeup can dramatically affect the strategies used in treating various anxiety disorders and their subsequent outcomes.

Case Study 1: The Border Collie and Separation Anxiety

Background:

Border Collies are often bred for their agility and intelligence but are also known to have a predisposition for separation anxiety (Serpell & Duffy, 2016). In this case, a 3-year-old Border Collie named Max exhibited severe separation anxiety symptoms, including destructive behavior and excessive vocalization.

Genetic Testing:

Upon advice from a veterinary behaviorist, a genetic test was performed that confirmed markers associated with separation anxiety in the breed.

Treatment Strategy:

With the genetic predisposition confirmed, a combination of targeted behavioral therapy and medication was initiated. A selective serotonin reuptake inhibitor (SSRI) was prescribed, alongside a structured desensitization and counterconditioning program.

Outcome:

Over a period of six months, Max showed significant improvement, and the frequency and intensity of his symptoms decreased substantially.

 Takeaway:

The targeted approach, informed by Max’s genetic predisposition, led to more effective and faster treatment outcomes (Overall, 2013).

Case Study 2: The Labrador Retriever and Noise Anxiety

 Background:

Bella, a 5-year-old Labrador Retriever, had acute reactions to loud noises like thunder and fireworks (Storengen et al., 2014).

Genetic Testing:

 Genetic screening revealed markers associated with heightened sensitivity to noise.

Treatment Strategy:

 Based on the genetic insights, Bella was prescribed fast-acting anti-anxiety medication to be administered before anticipated noise events, along with a behavioral modification plan to gradually desensitize her to such noises.

Outcome:

Bella showed marked improvements, with reduced physiological symptoms during noisy events.

Takeaway:

Genetic insights paved the way for a preemptive pharmacological approach, leading to the successful management of Bella’s noise anxiety (Storengen et al., 2014).

Case Study 3: The Mixed Breed and Social Anxiety

Background:

Rosie, a mixed-breed dog, exhibited signs of social anxiety around both humans and other dogs (van Rooy et al., 2018).

Genetic Testing:

Even though Rosie was a mixed breed, genetic testing revealed a significant percentage of a breed known for social anxiety predispositions.

Treatment Strategy:

The veterinarian opted for a combined approach of pharmacotherapy and socialization training tailored to the specific breeds present in Rosie’s genetic makeup.

Outcome:

Rosie’s social anxiety was substantially reduced, allowing her to interact more comfortably in various social settings.

Takeaway:

The genetic background information was crucial for a targeted and effective treatment strategy (van Rooy et al., 2018).

By examining these cases, we can see the powerful role that genetic understanding plays in tailoring treatment plans for dogs suffering from anxiety disorders. These real-world examples affirm that considering genetic background allows for more precise, effective interventions, thereby increasing the chances of successful outcomes.

Conclusion

Understanding the complexities of canine anxiety requires an approach that is as multifaceted as the condition itself. As this article has elaborated, genetics plays a significant role in the propensity for various types of anxiety disorders in dogs, ranging from separation and noise anxieties to more complex social anxieties (Serpell & Duffy, 2016; Storengen et al., 2014; van Rooy et al., 2018). Scientific advancements have given us invaluable tools, such as genetic testing, which can provide insights into a dog’s likelihood of developing these conditions (Overall, 2013; Oberbauer et al., 2017).

However, understanding the genetic predispositions is only part of the equation. Integrated approaches that consider both genetic and environmental factors are crucial for effective treatment and prevention. Case studies reveal the successful outcomes that are possible when an informed, targeted approach is taken (Overall, 2013; Serpell & Duffy, 2016; Storengen et al., 2014; van Rooy et al., 2018). As our understanding of the genetic underpinnings of canine behavior continues to grow, so does our capacity to more effectively treat these disorders.

The ethical considerations around breeding dogs with known predispositions to anxiety should also not be taken lightly. Breeders, veterinarians, and dog owners all share a responsibility to utilize the knowledge gained from behavioral genetics research to make informed, ethical choices (Oberbauer et al., 2017).

In closing, the genetics of canine anxiety is an evolving field, but one that holds tremendous promise for improving the quality of life for dogs and their human families. By combining a nuanced understanding of genetics with effective treatment strategies, we pave the way for more focused, effective interventions. Through this integrated approach, we not only treat symptoms but also get to the root of the problem, making it a win-win for both the dog and its human companions.

By appreciating the interplay between genetics and environment, and using that knowledge in practical applications, we can address canine anxiety in a much more holistic and effective manner. The integration of these aspects doesn’t just promise better mental health for our dogs but also a better understanding and stronger bond between dogs and their human caregivers.

References

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Turcsán, B., Miklósi, Á., & Kubinyi, E. (2017). Owner Perceived Differences Between Mixed-Breed and Purebred Dogs. PLOS ONE, 12(2), e0172720.

van Rooy, D., Arnott, E. R., Early, J. B., McGreevy, P., & Wade, C. M. (2018). Holding back the genes: limitations of research into canine behavioural genetics. Canine Genetics and Epidemiology, 5(1), 6.