Nav: Home

Overlapping genomic regions underlie canine fearfulness and human mental disorders

January 23, 2019

Researchers in the Hannes Lohi research group in the University of Helsinki focused on two forms of canine fearfulness: noise sensitivity and general fearfulness. The latter encompasses the fear of unfamiliar humans and new situations. Among Finnish dogs, noise sensitivity has been observed in as much as 40% of the population, while, according to estimates, one in four dogs suffers from fearfulness.

Prior studies have suggested that canine fearfulness corresponds with human anxiety disorders, potentially could potentially serve as a disease model for human disorders.

"Fear is an innate and vital reaction. However, when it becomes excessive and an overriding feature in a dog's life, it turns into a behavioural problem," says Riika Sarviaho, a doctoral student.

Canine behavioural disorders include separation anxiety, generalised anxiety disorder and various phobias. Fear can be expressed as aggression, which may, at its worst, lead to attacks against other dogs or humans.

More than 300 owners of German Shepherds filled out a behavioural survey for the study, which had already been validated as a reliable tool on the basis of behavioural tests. Based on the responses, a score depicting the intensity of fearfulness was given to each dog.

"Interpreting and measuring behaviour is a challenging but important stage of successful research. Extremely fearful dogs are excluded from the population, leaving their numbers often very low. To expand the dataset and power of the study, less extreme cases were also included in the study," Professor Hannes Lohi adds.

Nearly identical genomic regions

On the basis of genetic research, generalised anxiety in dogs was associated with a region of canine chromosome 7 that corresponds with a certain region in human chromosome 18.

"This is an extremely fascinating finding, since chromosomal region 18p11 has been linked with several neuropsychiatric diseases, such as schizophrenia and bipolar affective disorder already in the 1990s. Fear is an integral part of many mental disorders. Schizophrenia has even been described as chronic fear. The results indicate that canine fearfulness and human psychotic disorders may have similar underlying factors," Sarviaho notes.

In further studies, the significance of the chromosomal region should be verified and the gene variants associated with fearfulness identified. With the help of genetic findings, it will be easier to understand the pathogenetic mechanisms of canine fearfulness in neurons and to compare them with corresponding human diseases.

Noise sensitivity seen also in humans

Dogs' sensitivity to noise is apparent when they express fear, for example during a thunderstorm or fireworks. In veterinary medicine, noise sensitivity is considered a diagnostic condition of its own, and dogs that are sensitive to noise are not necessarily otherwise fearful.

Sensitivity to sound also occurs among humans; for example, in human misophonia and hyperacusis, certain sounds cause feelings of discomfort, fear or even rage. However, the genetic background of these diseases remains poorly known in both human and veterinary medicine.

"The genomic region associated with noise sensitivity in the German Shepherd breed is interesting. It includes several genes that have been associated with human mental disorders. Among others, it includes a gene that codes a receptor for the neurotransmitter glutamate and has been linked with both anxiety and hearing. Another gene of interest is the oxytocin receptor gene OXTR, which has been associated with anxiety, stress and social behaviour. Further analyses of this region will be carried out as well," Professor Lohi explains.

The findings indicate that canine fearfulness is hereditary. To verify the role of the newly discovered genomic regions and to identify other new regions and actual risk genes requires further research with an even larger dataset.

Gene discoveries have so far been rare in canine behavioural studies, and the recently published study is the first one to be carried out within a single breed, resulting in the identification of a significant link between canine fearfulness and genomic regions.
-end-


University of Helsinki

Related Mental Disorders Articles:

A new approach to diagnosing mental disorders could become an alternative to DSM-5
A consortium of psychiatrists and psychologists from universities around the world, co-led by Stony Brook University, University of Minnesota and University of Notre Dame researchers, has proposed a new approach to diagnosing mental disorders.
Loss of spouse or partner to suicide linked to physical, mental disorders
People who lose a partner to suicide are at increased risk for a number of mental and physical disorders, including cancer, depression, herniated discs and mood disorders than those in the general population, new Johns Hopkins Bloomberg School of Public Health research suggests.
Non-severe infections can cause serious mental disorders
Previous studies have shown that patients who are hospitalised with severe infections have an increased risk of developing schizophrenia and depression.
More with mental illness and substance use disorders have health insurance
Significantly more people with mental illness and substance use disorders had insurance coverage in 2014 due to the expansion of health insurance under the Affordable Care Act, but many barriers to treatment remain, new Johns Hopkins Bloomberg School of Public Health research suggests.
American death rate from drugs, alcohol, and mental disorders nearly triples since 1980
The study, published in the Dec. 13th issue of JAMA, examines deaths in 21 cause groups, ranging from chronic illnesses like diabetes and other endocrine diseases, to infectious diseases, such as HIV/AIDS and tuberculosis, to accidents, including traffic fatalities.
Facebook updates could help understand -- and potentially treat -- mental health disorders
Our Facebook status updates, 'likes' and even photos could help researchers better understand mental health disorders with the right ethical safeguards, argue researchers from the University of Cambridge, who suggest that social networks may even be used in future to provide support and interventions, particularly among young people.
Recent cancer diagnosis associated with increased risk of mental health disorders
A recent cancer diagnosis was associated with increased risk for some mental health disorders and increased use of psychiatric medications, according to a new study published online by JAMA Oncology that used data from Swedish population and health registers.
Mind-altering drugs could treat mental disorders
Psychedelic compounds have had a colorful past. Although initially investigated for medical uses, they were banned after cultural and political times changed in the 1960s and 1970s.
What is risk of mental health, substance use disorders if you use marijuana?
With more states legalizing marijuana for medical and recreational use, there are renewed clinical and policy concerns about the mental health effects of the drug.
Transgender veterans diagnosed with significantly more mental and medical health disorders
The first large, controlled study of health disparities between clinically diagnosed transgender and non-transgender patients -- based on the medical records of more than 5,000 patients treated in the Veterans Health Administration -- showed that transgender veterans had a significantly greater prevalence of numerous psychiatric and medical conditions.

Related Mental Disorders Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Setbacks
Failure can feel lonely and final. But can we learn from failure, even reframe it, to feel more like a temporary setback? This hour, TED speakers on changing a crushing defeat into a stepping stone. Guests include entrepreneur Leticia Gasca, psychology professor Alison Ledgerwood, astronomer Phil Plait, former professional athlete Charly Haversat, and UPS training manager Jon Bowers.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".