Gene-Edited Puppies Will Melt Your Heart—but Won’t Trigger Your Allergies

Scientist Matt Walker always wanted a dog, but allergies prevented him from having one.

As an undergrad at Harvard and then a research associate at Columbia University, he was using Crispr , the Nobel Prize–winning gene editing technology, in lab experiments. He wondered, could he use gene editing to make allergy-free dogs—and help his pet ownership dream come true?

The answer came in beagle form. Bailey and Alfie are two young beagles that can do tricks like any other dog, but they lack the protein that causes sniffles. They’re the culmination of years of work at Kindred Companion Sciences, a biotech company Walker founded in 2020 that emerged from stealth this week with the two pups in tow.

In a scientific paper published on Wednesday in The Crispr Journal , Walker and his colleagues detail how they used gene editing to remove an allergy-causing protein in the dogs. The culprit for most dog allergy-sufferers is a protein called Can f 1, which is found in dander, hair, and saliva. It’s the most common dog allergen, causing reactions in more than half of people with dog allergies. (There are several other Can f proteins that can cause allergies.) Studies have found that even dog breeds labeled as hypoallergenic often carry equal or higher levels of these proteins compared to other dogs.

“This motivated the question of whether we could use gene editing to directly get rid of that allergen at its source,” Walker says.

The Kindred team used Crispr to knock out the gene that produces Can f 1 in skin cells taken from a female beagle. They then used a cloning method called somatic cell nuclear transfer to inject the edited cells into eggs from donor beagles. After creating 25 embryos with the Can f 1 gene edit, they transferred them to a surrogate. Two of the embryos developed to term, resulting in the birth of two puppies.

The dogs’ birth weights were normal, and they had no congenital abnormalities. But the team needed to know whether the allergy-inducing protein had actually been eliminated. First, they sequenced the dogs’ DNA to confirm that the edit was present. Then, they took samples of the dogs’ saliva and dander to measure levels of the Can f 1 protein. Testing showed no detectable protein compared to samples from non-edited dogs, including a beagle, poodle, and golden doodle, which had clear Can f 1 signals.

To make sure the dogs wouldn’t cause allergic reactions in people, Walker served as the guinea pig for a skin prick test, which involves applying small drops of allergens in liquid form on the skin and gently pricking the surface to see if there’s a reaction. Drops from the edited dog did not elicit a skin response ,while drops from a non-edited dog did.