A new genetic study published Nov. 24 finds that most modern dog breeds carry small but measurable amounts of wolf ancestry. Coverage from Cbsnews has highlighted this story.

Researchers analyzed genomes from more than 2,700 published genomes, including 1,872 modern dogs, to measure the extent of interbreeding between dogs and wolves that occurred in the past few thousand years and to identify which breeds carry the strongest wolf signals.

The peer-reviewed paper appeared in PNAS and draws on a large set of published genomes to quantify how much wolf DNA persists in contemporary dog populations. The analysis measured ancestry across breeds and free-roaming “village dogs,” offering a broad view of dog–wolf genetic entanglement. Reporting by Sciencedaily offers additional detail on this case.

Among intentionally bred wolfdogs, the study identified Czechoslovakian wolfdogs and Saarloos wolfdogs as having the highest degree of wolf ancestry at 23-40%. However, among typical dog breeds, the Great Anglo-French Tricolor Hound had the strongest signal at 4.7-5.7%. At the opposite end of the spectrum, the researchers reported that a Chihuahua’s genome contains about 0.2% wolf-derived DNA. Every tested “village dog” in the study carried detectable wolf DNA.

Audrey Lin, evolutionary biologist at the American Museum of Natural History, summarized how the findings shift previous thinking about dog genomes: “Prior to this study, the leading science seemed to suggest that in order for a dog to be a dog, there can’t be very much wolf DNA present, if any.” She added a lighter observation about small breeds: “This completely makes sense to anyone who owns a Chihuahua.”

Logan Kistler, curator of archaeobotany and archaeogenomics at the Smithsonian National Museum of Natural History in Washington, D.C., framed the results as part of dogs’ long history alongside humans. “Dogs are our buddies, but apparently wolves have been a big part of shaping them into the companions we know and love today,” he said. As covered by Livescience, readers can explore more context around the event.

The study’s scope — thousands of genomes spanning dogs and wolves — allowed researchers to detect low levels of wolf ancestry that smaller datasets might miss. By analyzing data across many breeds and free-roaming populations, the team was able to show that detectable wolf DNA is widespread, not confined to a few specialized wolfdog breeds.

Findings like which breeds show the strongest wolf signal and the presence of wolf ancestry in village dogs were highlighted in institutional coverage of the research; the Smithsonian’s write-up places the study within ongoing work at the National Museum of Natural History, while the journal publication provides the full technical details and methodology.

Researchers described the wolf ancestry as small in most breeds but measurable using modern genomic tools. The presence of wolf DNA across a wide set of dogs suggests repeated interbreeding events after initial domestication, leaving a faint but persistent genetic legacy in many modern dogs.

The publication date of the study was Nov. 24, and the results were released through the journal PNAS and accompanying institutional summaries.

Source

Original reporting: view the original article.