Dog's DNA may be damaged from domestication

Domesticating dogs from gray wolves more than 15,000 years ago involved artificial selection and inbreeding, and this process may have inadvertently caused harmful genetic changes in our canine pets, new research suggests.

The researchers analysed the complete genome sequences of 19 wolves, 25 wild dogs from 10 different countries, and 46 domesticated dogs from 34 different breeds.

They found that domestication may have led to a rise in the number of harmful genetic changes in dogs, likely as a result of temporary reductions in population size known as bottlenecks.

"Population bottlenecks tied to domestication, rather than recent inbreeding, likely led to an increased frequency of deleterious genetic variations in dogs," said senior author of the research Kirk Lohmueller, assistant professor of ecology and evolutionary biology at University of California, Los Angeles.

"Our research suggests that such variants may have piggybacked onto positively selected regions, which were also enriched in disease-related genes," Lohmueller said.

"Thus, the use of small populations artificially bred for desired traits, such as smaller body size or coat colour, may have led to an accumulation of harmful genetic variations in dogs," Lohmueller noted.

Such variations, Lohmueller said, could potentially lead to a number of different developmental disorders and other health risks.

The research was published in the journal Proceedings of the National Academy of Sciences (PNAS).