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Most Domesticated Dogs Originated in Middle East, Study Suggests
Most domesticated dogs likely originated from gray wolves in the Middle East, with only some possibly originating in Europe or Asia, according to a new genetic analysis by an international team of scientists led by UCLA biologists. The team reported genetic data from 912 dogs from 85 breeds (including all the major ones) and 225 wild gray wolves (the ancestor of domesticated dogs) worldwide, including populations from North America, Europe, the Middle East and East Asia. The scientists used molecular genetic techniques to analyze more than 48,000 genetic markers (SNPs) on a genome-wide basis in the dogs and wolves. The team has not yet pinpointed a specific location of origin in the Middle East. The new research results were published online on March 17, 2010 in Nature. In their work, the researchers found evidence for certain candidate genes that might have been important in the early domestication of dogs. There was evidence of positive selection for two SNPs located near genes associated with memory formation and/or behavioral sensitization in mouse or human studies. There was also evidence of positive selection for a third SNP that is located near the dog counterpart of the gene associated with Williams-Beuren syndrome in humans. This syndrome is characterized by social traits such as exceptional gregariousness. The current results were consistent with earlier analyses suggesting that three groups of ancient breeds (origins >500 years ago) are distinct from modern domestic dogs that are the products of the controlled breeding practices of the Victorian era (circa 1830-1900). These ancient breeds consist of an Asian group (dingo, New Guinea singing dog, chow chow, Akita, and Chinese Shar Pei), a Middle Eastern group (Afghan hound and saluki), and a northern group (Alaskan malamute and Siberian husky).