Now, two Beagles could offer a glimpse of a future in which a dog allergy no longer automatically means living without a canine companion. The result is two healthy dogs that do not appear to produce detectable Can f 1 in their saliva or fur. Researchers tested samples from the genetically modified dogs alongside samples from other dogs. The researchers used CRISPR gene-editing technology to alter the DNA responsible for producing the protein. The researchers have also discussed the possibility of genetically modified dogs being used as service animals.