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Variations in just five genes in a portion of the dog genome, linked to their social behavior, have also been implicated in behavioral and neurological disorders in people, like schizophrenia, autism, and aggression, according to a recent study involving more than 430 untrained, lab-raised beagles.The goal behind the study was to understand the genetic underpinning of domestication – What is it that played a role in turning the wolf, which is not really a social creature to begin with, into the sociable domestic dog. Scientists discovered that there was some genetic play at work. In the study, the scientists provided each of the beagles with a box that held three treats. All of them could be smelled and were perfectly visible as well, but there was a catch. The dogs had to move a sliding lid to access the treat. For the third treat, the lid was locked. After easily gaining access to the first two, the dogs became confident that this is not a difficult task. However, when they came face to face with the third lid, the problem seemed impossible.After a couple of attempts, the dogs started to look at the woman observer present in the room, who for all practical purposes was a stranger as far as the dog was concerned. Some of the animals glanced at her and then back at the locked lid. Other dogs approached her and even made physical contact with her.Following this little exercise, the scientists scanned the differences in DNA between the dogs that spent the least and most time close to the woman after they failed to gain access to the third treat. While doing this, the researchers were able to identify genetic markers on the 26th chromosome that was linked to social interactions. They concluded that there were genetic variations that made some dogs more sociable than the others, and these were the variants that were selected during the process of domestication.One of the genetic markers was in the SEZ6L gene, which is one of the genes that is most commonly linked to the autism spectrum disorder in humans, and two of them were located in the ARVCF gene, which is linked to schizophrenia. Another gene found in the region, the COMT gene, is most commonly linked to aggression in young children who suffer from ADHD.These results indicate that the dogs might serve as a good model system for studying social disorders in human beings. Of course, it goes without saying that these genes don't explain the individual personalities of the dogs themselves. The genetic contribution to the variation is close to 30 percent and the rest of it has more to do with their experience. Even if one of the five genes involved exerts an effect, then it is highly likely that it is only a small part of the story.