Genetic research: the origin of small dogs - in the Middle East

Researchers from the University of California, Los Angeles discovered that the same mutation present in gray wolves in the Middle East is common in all small dog breeds.

Genetic research has revealed that the small dog breeds originated in the Middle East over 12 thousand years ago. The researchers who published their research in the free journal BMC Biology traced the evolutionary history of the IGF1 gene, and found that a version of the gene common in small dogs came as a result of domestication by the Middle Eastern gray wolf.

Malisha Gray and Robert Wayne of the University of California, Los Angeles led a group of researchers who reviewed samples from large populations of gray wolves. According to Gray "the mutation to a small body size preceded the domestication of dogs. However, since the small dogs carry this version of the IGF1 gene, it is likely that it arrived early in their history. Our study showed that the version of the IGF1 gene that appears in small dogs is close to the one found in the Middle Eastern wolves and is consistent with the knowledge of the origin of the small dogs from this area."

In archaeological digs in the Middle East, remains of small dogs dating back 12 years were uncovered. Sites in Belgium, Germany and western Russia contain older remains of dogs (from 13,000-31,000 years ago), but all were of large dogs. These findings support the hypothesis of Gray and her colleagues that the small-bodied dogs evolved in the Middle East.

A decrease in body size is a common feature of the domestication process that has also been seen in other domesticated animals including cattle, pigs and goats. According to Gray, "Small body size was a desirable trait in crowded agricultural societies, where dogs lived part of the time indoors and the rest of the time in outdoor spaces."

to the notice of the researchers