Dogs' Ancestry Revealed: Most Breeds Carry Wolf DNA

U.S. scientists have announced a significant discovery regarding the genetic makeup of domestic dogs, revealing that nearly two-thirds of dog breeds, including chihuahuas, possess detectable amounts of wolf DNA.

Logan Kistler, a curator at the Smithsonian Museum of Natural History and co-author of the study, stated that this wolf DNA is not merely a remnant from when dogs diverged from wolves approximately 20,000 years ago.

Instead, the findings suggest that interbreeding between domesticated dogs and wild wolves has occurred within the last few thousand years. This revelation was detailed in a study published in the Proceedings of the National Academy of Sciences.

Researchers analyzed thousands of dog and wolf genomes found in publicly available databases, leading to the conclusion that over 64 percent of modern dog breeds have some level of wolf ancestry. Remarkably, even small breeds like the chihuahua carry about 0.2 percent wolf DNA, which study author Audrey Lin humorously noted is consistent with the behavior observed in chihuahuas.

The breeds with the highest proportions of wolf DNA were identified as Czechoslovakian and Saarloos wolfdogs, with up to 40 percent wolf DNA present. Among common pet breeds, the Grand Anglo-Francais Tricolore hound exhibited the highest wolf ancestry at approximately five percent, while sighthounds like Salukis and Afghans also showed significant levels.

In a surprising contrast, Saint Bernards were found to have no detectable wolf DNA. The study also highlighted that 100 percent of village dogs, which live among human settlements but are not owned, possess wolf ancestry.

Kistler speculated that these village dogs often have more opportunities to breed with wolves, especially when female wolves become isolated from their packs due to human activities. The research drew correlations between the amount of wolf DNA and behavioral traits, indicating that breeds with higher percentages of wolf ancestry are often described as more independent or territorial, while those with less are typically seen as friendly and trainable.

Notably, Tibetan dog breeds, such as the Lhasa Apso, possess a gene called EPAS1, linked to adaptation at high altitudes, which also appears in Tibetan wolves, illustrating how dogs have evolved alongside their wild ancestors to adapt to various environments.

This groundbreaking research sheds light on the complex evolutionary history of canines and their ongoing connection to wolves, as reported by Daniel Lawler in the National Post on November 24, 2023.