Those early studies “raised both the potential of what we could learn from dogs, but also that we would need larger sample sizes to do it really well,” said Elinor Karlsson, a geneticist at the UMass Chan School of Medicine and the Broad Institute. And so, researchers began creating large citizen science projects, seeking DNA samples and data from dogs across the United States.
Pet owners rose to the challenge. The Golden Retriever Lifetime Study, which began recruiting in 2012, is tracking more than 3,000 dogs in an effort to identify genetic and environmental risk factors for cancer, which is particularly common in the breed. As of 2019, the Dog Aging Project, a long-term study of health and longevity, has enrolled nearly 50,000 dogs.
Dr. Karlsson’s work, Darwin’s Dogs, is at 44,000 canines and counting. (About 4,000 have had their genomes sequenced.) Researchers mine the data for clues about bone cancer, compulsive behavior and other traits. Among the early findings: Although many behavioral traits, such as sociability and trainability, are heritable, they are widely distributed across the canine kingdom, and breed is a poor predictor of an individual dog’s personality.
This spring, Dr. Karlsson revealed a long-awaited expansion: Darwin’s Cats. “I’m a cat person – I’ve never had a dog,” she said. Later, in an email, he added: “I would love to know if ‘the cat sleeps on your head’ is influenced by genetics.”
Data drivers
These projects became possible as genomic sequencing became faster and more accessible. But the “tremendous enthusiasm” of pet owners was integral, said Dr. Ostrander, who now leads the Dog10K project, an effort to create a comprehensive global catalog of dog genetic diversity.
