By Judith de Jorge Gama
Dogs have accompanied man for at least 15,000 years, when they emerged from among the meekest, most curious or interested wolves who approached the settlements of our ancestors. Since then, they have been part of the human family, developing different social skills that allow them to communicate and cooperate with us like no other species is capable of. For example, they form emotional bonds with their owners, they are sensitive to our gestures and they are known to recognize our emotions in facial expressions. Also, they try to communicate with people, seeking their attention or turning to them when they need help solving a problem.
But where does all that sociability come from? Is it something innate or is it acquired during the education of the animal? Researchers believe that all these social skills have a genetic basis, as even puppies are able to read human communication signals while wolves cannot, even though they are used to the presence of man.
Now, a team from Linköping University in Sweden has identified five genes related to the social skills of our best friends and it turns out, surprisingly, that in humans some of them are linked to behavioral disorders, such as autism, schizophrenia or aggression in adolescents with attention deficit disorder.
The key genes
Next, the genomes of 190 beagles were analyzed in what is called a genome-wide association study (GWAS), and the researchers identified two regions that contain a total of five candidate genes that may be related to those social behaviors. For example, a genetic marker within the SEZ6L gene has to do with time spent in physical contact with humans, while two other markers in the ARVCF gene were linked to the search for human contact. Interestingly, these genes and others found in the same linkage blocks affect social skills in humans, and are related to autism spectrum disorders, schizophrenia or aggressiveness.
The results, as reported by the authors in the journal Scientific Report, shed light on that very special relationship between humans and dogs, and may help to understand not only the domestication process but also some disorders of human behavior.