The
domestication1 of dogs may have inadvertently caused harmful
genetic2 changes, a UCLA-led study suggests.
Domesticating3 dogs from gray wolves more than 15,000 years ago involved artificial selection and inbreeding, but the effects of these processes on dog genomes have been little-studied.
UCLA researchers
analyzed4 the complete genome sequences of 19 wolves; 25 wild dogs from 10 different countries; and 46
domesticated5 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
bottlenecks6.
"Population bottlenecks tied to domestication, rather than recent inbreeding, likely led to an increased frequency of deleterious genetic variations in dogs," said Kirk Lohmueller, senior author of the research and assistant professor of ecology and
evolutionary7 biology in the UCLA College.
"Our research suggests that such
variants8 may have piggybacked onto
positively9 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 color, may have led to an accumulation of harmful genetic variations in dogs."